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DRM :ade : add cmd file function #2
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DRM :ade : add cmd file function #2
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Signed-off-by: kongxinwei <[email protected]>
DRM :ade : add cmd file function |
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DRM :ade : add cmd file function
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Kernel testing triggered this warning: | WARNING: CPU: 0 PID: 13 at kernel/sched/core.c:1156 do_set_cpus_allowed+0x7e/0x80() | Modules linked in: | CPU: 0 PID: 13 Comm: migration/0 Not tainted 4.2.0-rc1-00049-g25834c7 #2 | Call Trace: | dump_stack+0x4b/0x75 | warn_slowpath_common+0x8b/0xc0 | warn_slowpath_null+0x22/0x30 | do_set_cpus_allowed+0x7e/0x80 | cpuset_cpus_allowed_fallback+0x7c/0x170 | select_fallback_rq+0x221/0x280 | migration_call+0xe3/0x250 | notifier_call_chain+0x53/0x70 | __raw_notifier_call_chain+0x1e/0x30 | cpu_notify+0x28/0x50 | take_cpu_down+0x22/0x40 | multi_cpu_stop+0xd5/0x140 | cpu_stopper_thread+0xbc/0x170 | smpboot_thread_fn+0x174/0x2f0 | kthread+0xc4/0xe0 | ret_from_kernel_thread+0x21/0x30 As Peterz pointed out: | So the normal rules for changing task_struct::cpus_allowed are holding | both pi_lock and rq->lock, such that holding either stabilizes the mask. | | This is so that wakeup can happen without rq->lock and load-balance | without pi_lock. | | From this we already get the relaxation that we can omit acquiring | rq->lock if the task is not on the rq, because in that case | load-balancing will not apply to it. | | ** these are the rules currently tested in do_set_cpus_allowed() ** | | Now, since __set_cpus_allowed_ptr() uses task_rq_lock() which | unconditionally acquires both locks, we could get away with holding just | rq->lock when on_rq for modification because that'd still exclude | __set_cpus_allowed_ptr(), it would also work against | __kthread_bind_mask() because that assumes !on_rq. | | That said, this is all somewhat fragile. | | Now, I don't think dropping rq->lock is quite as disastrous as it | usually is because !cpu_active at this point, which means load-balance | will not interfere, but that too is somewhat fragile. | | So we end up with a choice of two fragile.. This patch fixes it by following the rules for changing task_struct::cpus_allowed with both pi_lock and rq->lock held. Reported-by: kernel test robot <[email protected]> Reported-by: Sasha Levin <[email protected]> Signed-off-by: Wanpeng Li <[email protected]> [ Modified changelog and patch. ] Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
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The renesas-irqc interrupt controller is cascaded to the GIC. Hence when propagating wake-up settings to its parent interrupt controller, the following lockdep warning is printed: ============================================= [ INFO: possible recursive locking detected ] 4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280 Not tainted --------------------------------------------- s2ram/1072 is trying to acquire lock: (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98 but task is already holding lock: (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&irq_desc_lock_class); lock(&irq_desc_lock_class); *** DEADLOCK *** May be due to missing lock nesting notation 6 locks held by s2ram/1072: #0: (sb_writers#7){.+.+.+}, at: [<c012eb14>] __sb_start_write+0xa0/0xa8 #1: (&of->mutex){+.+.+.}, at: [<c019396c>] kernfs_fop_write+0x4c/0x1bc #2: (s_active#24){.+.+.+}, at: [<c0193974>] kernfs_fop_write+0x54/0x1bc #3: (pm_mutex){+.+.+.}, at: [<c008213c>] pm_suspend+0x10c/0x510 #4: (&dev->mutex){......}, at: [<c02af3c4>] __device_suspend+0xdc/0x2cc #5: (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98 stack backtrace: CPU: 0 PID: 1072 Comm: s2ram Not tainted 4.2.0-ape6evm-10725-g50fcd7643c034198 torvalds#280 Hardware name: Generic R8A73A4 (Flattened Device Tree) [<c0018078>] (unwind_backtrace) from [<c00144f0>] (show_stack+0x10/0x14) [<c00144f0>] (show_stack) from [<c0451f14>] (dump_stack+0x88/0x98) [<c0451f14>] (dump_stack) from [<c007b29c>] (__lock_acquire+0x15cc/0x20e4) [<c007b29c>] (__lock_acquire) from [<c007c6e0>] (lock_acquire+0xac/0x12c) [<c007c6e0>] (lock_acquire) from [<c0457c00>] (_raw_spin_lock_irqsave+0x40/0x54) [<c0457c00>] (_raw_spin_lock_irqsave) from [<c008d3fc>] (__irq_get_desc_lock+0x58/0x98) [<c008d3fc>] (__irq_get_desc_lock) from [<c008ebbc>] (irq_set_irq_wake+0x20/0xf8) [<c008ebbc>] (irq_set_irq_wake) from [<c0260770>] (irqc_irq_set_wake+0x20/0x4c) [<c0260770>] (irqc_irq_set_wake) from [<c008ec28>] (irq_set_irq_wake+0x8c/0xf8) [<c008ec28>] (irq_set_irq_wake) from [<c02cb8c0>] (gpio_keys_suspend+0x74/0xc0) [<c02cb8c0>] (gpio_keys_suspend) from [<c02ae8cc>] (dpm_run_callback+0x54/0x124) Avoid this false positive by using a separate lockdep class for IRQC interrupts. Signed-off-by: Geert Uytterhoeven <[email protected]> Cc: Grygorii Strashko <[email protected]> Cc: Magnus Damm <[email protected]> Cc: Jason Cooper <[email protected]> Link: http://lkml.kernel.org/r/1441798974-25716-2-git-send-email-geert%[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
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The renesas-intc-irqpin interrupt controller is cascaded to the GIC. Hence when propagating wake-up settings to its parent interrupt controller, the following lockdep warning is printed: ============================================= [ INFO: possible recursive locking detected ] 4.2.0-armadillo-10725-g50fcd7643c034198 torvalds#781 Not tainted --------------------------------------------- s2ram/1179 is trying to acquire lock: (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94 but task is already holding lock: (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&irq_desc_lock_class); lock(&irq_desc_lock_class); *** DEADLOCK *** May be due to missing lock nesting notation 7 locks held by s2ram/1179: #0: (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8 #1: (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0 #2: (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0 #3: (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20 #4: (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248 #5: (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240 #6: (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94 stack backtrace: CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198 Hardware name: Generic R8A7740 (Flattened Device Tree) [<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c) [<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28) [<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88) [<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc) [<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58) [<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94 [<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100) [<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c) [<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50 [<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100) [<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0) [<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c) Avoid this false positive by using a separate lockdep class for INTC External IRQ Pin interrupts. Signed-off-by: Geert Uytterhoeven <[email protected]> Cc: Grygorii Strashko <[email protected]> Cc: Magnus Damm <[email protected]> Cc: Jason Cooper <[email protected]> Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
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The OPP list needs to be protected against concurrent accesses. Using simple RCU read locks does the trick and gets rid of the following lockdep warning: =============================== [ INFO: suspicious RCU usage. ] 4.2.0-next-20150908 #1 Not tainted ------------------------------- drivers/base/power/opp.c:460 Missing rcu_read_lock() or dev_opp_list_lock protection! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 4 locks held by kworker/u8:0/6: #0: ("%s""deferwq"){++++.+}, at: [<c0040d8c>] process_one_work+0x118/0x4bc #1: (deferred_probe_work){+.+.+.}, at: [<c0040d8c>] process_one_work+0x118/0x4bc #2: (&dev->mutex){......}, at: [<c03b8194>] __device_attach+0x20/0x118 #3: (prepare_lock){+.+...}, at: [<c054bc08>] clk_prepare_lock+0x10/0xf8 stack backtrace: CPU: 2 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.0-next-20150908 #1 Hardware name: NVIDIA Tegra SoC (Flattened Device Tree) Workqueue: deferwq deferred_probe_work_func [<c001802c>] (unwind_backtrace) from [<c00135a4>] (show_stack+0x10/0x14) [<c00135a4>] (show_stack) from [<c02a8418>] (dump_stack+0x94/0xd4) [<c02a8418>] (dump_stack) from [<c03c6f6c>] (dev_pm_opp_find_freq_ceil+0x108/0x114) [<c03c6f6c>] (dev_pm_opp_find_freq_ceil) from [<c0551a3c>] (dfll_calculate_rate_request+0xb8/0x170) [<c0551a3c>] (dfll_calculate_rate_request) from [<c0551b10>] (dfll_clk_round_rate+0x1c/0x2c) [<c0551b10>] (dfll_clk_round_rate) from [<c054de2c>] (clk_calc_new_rates+0x1b8/0x228) [<c054de2c>] (clk_calc_new_rates) from [<c054e44c>] (clk_core_set_rate_nolock+0x44/0xac) [<c054e44c>] (clk_core_set_rate_nolock) from [<c054e4d8>] (clk_set_rate+0x24/0x34) [<c054e4d8>] (clk_set_rate) from [<c0512460>] (tegra124_cpufreq_probe+0x120/0x230) [<c0512460>] (tegra124_cpufreq_probe) from [<c03b9cbc>] (platform_drv_probe+0x44/0xac) [<c03b9cbc>] (platform_drv_probe) from [<c03b84c8>] (driver_probe_device+0x218/0x304) [<c03b84c8>] (driver_probe_device) from [<c03b69b0>] (bus_for_each_drv+0x60/0x94) [<c03b69b0>] (bus_for_each_drv) from [<c03b8228>] (__device_attach+0xb4/0x118) ata1: SATA link down (SStatus 0 SControl 300) [<c03b8228>] (__device_attach) from [<c03b77c8>] (bus_probe_device+0x88/0x90) [<c03b77c8>] (bus_probe_device) from [<c03b7be8>] (deferred_probe_work_func+0x58/0x8c) [<c03b7be8>] (deferred_probe_work_func) from [<c0040dfc>] (process_one_work+0x188/0x4bc) [<c0040dfc>] (process_one_work) from [<c004117c>] (worker_thread+0x4c/0x4f4) [<c004117c>] (worker_thread) from [<c0047230>] (kthread+0xe4/0xf8) [<c0047230>] (kthread) from [<c000f7d0>] (ret_from_fork+0x14/0x24) Signed-off-by: Thierry Reding <[email protected]> Fixes: c4fe70a ("clk: tegra: Add closed loop support for the DFLL") [[email protected]: Unlock rcu on error path] Signed-off-by: Vince Hsu <[email protected]> [[email protected]: Dropped second hunk that nested the rcu read lock unnecessarily] Signed-off-by: Stephen Boyd <[email protected]>
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…t initialized. In case something goes wrong with power well initialization we were calling intel_prepare_ddi during boot while encoder list isnt't initilized. [ 9.618747] i915 0000:00:02.0: Invalid ROM contents [ 9.631446] [drm] failed to find VBIOS tables [ 9.720036] BUG: unable to handle kernel NULL pointer dereference at 00000000 00000058 [ 9.721986] IP: [<ffffffffa014eb72>] ddi_get_encoder_port+0x82/0x190 [i915] [ 9.723736] PGD 0 [ 9.724286] Oops: 0000 [#1] PREEMPT SMP [ 9.725386] Modules linked in: intel_powerclamp snd_hda_intel(+) coretemp crc 32c_intel snd_hda_codec snd_hda_core serio_raw snd_pcm snd_timer i915(+) parport _pc parport pinctrl_sunrisepoint pinctrl_intel nfsd nfs_acl [ 9.730635] CPU: 0 PID: 497 Comm: systemd-udevd Not tainted 4.3.0-rc2-eywa-10 967-g72de2cfd-dirty #2 [ 9.732785] Hardware name: Intel Corporation Cannonlake Client platform/Skyla ke DT DDR4 RVP8, BIOS CNLSE2R1.R00.X021.B00.1508040310 08/04/2015 [ 9.735785] task: ffff88008a704700 ti: ffff88016a1ac000 task.ti: ffff88016a1a c000 [ 9.737584] RIP: 0010:[<ffffffffa014eb72>] [<ffffffffa014eb72>] ddi_get_enco der_port+0x82/0x190 [i915] [ 9.739934] RSP: 0000:ffff88016a1af710 EFLAGS: 00010296 [ 9.741184] RAX: 000000000000004e RBX: ffff88008a9edc98 RCX: 0000000000000001 [ 9.742934] RDX: 000000000000004e RSI: ffffffff81fc1e82 RDI: 00000000ffffffff [ 9.744634] RBP: ffff88016a1af730 R08: 0000000000000000 R09: 0000000000000578 [ 9.746333] R10: 0000000000001065 R11: 0000000000000578 R12: fffffffffffffff8 [ 9.748033] R13: ffff88016a1af7a8 R14: ffff88016a1af794 R15: 0000000000000000 [ 9.749733] FS: 00007eff2e1e07c0(0000) GS:ffff88016fc00000(0000) knlGS:00000 00000000000 [ 9.751683] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9.753083] CR2: 0000000000000058 CR3: 000000016922b000 CR4: 00000000003406f0 [ 9.754782] Stack: [ 9.755332] ffff88008a9edc98 ffff88008a9ed800 ffffffffa01d07b0 00000000fffb9 09e [ 9.757232] ffff88016a1af7d8 ffffffffa0154ea7 0000000000000246 ffff88016a370 080 [ 9.759182] ffff88016a370080 ffff88008a9ed800 0000000000000246 ffff88008a9ed c98 [ 9.761132] Call Trace: [ 9.761782] [<ffffffffa0154ea7>] intel_prepare_ddi+0x67/0x860 [i915] [ 9.763332] [<ffffffff81a56996>] ? _raw_spin_unlock_irqrestore+0x26/0x40 [ 9.765031] [<ffffffffa00fad01>] ? gen9_read32+0x141/0x360 [i915] [ 9.766531] [<ffffffffa00b43e1>] skl_set_power_well+0x431/0xa80 [i915] [ 9.768181] [<ffffffffa00b4a63>] skl_power_well_enable+0x13/0x20 [i915] [ 9.769781] [<ffffffffa00b2188>] intel_power_well_enable+0x28/0x50 [i915] [ 9.771481] [<ffffffffa00b4d52>] intel_display_power_get+0x92/0xc0 [i915] [ 9.773180] [<ffffffffa00b4fcb>] intel_display_set_init_power+0x3b/0x40 [i91 5] [ 9.774980] [<ffffffffa00b5170>] intel_power_domains_init_hw+0x120/0x520 [i9 15] [ 9.776780] [<ffffffffa0194c61>] i915_driver_load+0xb21/0xf40 [i915] So let's protect this case. My first attempt was to remove the intel_prepare_ddi, but Daniel had pointed out this is really needed to restore those registers values. And Imre pointed out that this case was without the flag protection and this was actually where things were going bad. So I've just checked and this indeed solves my issue. The regressing intel_prepare_ddi call was added in commit 1d2b952 Author: Damien Lespiau <[email protected]> Date: Fri Mar 6 18:50:53 2015 +0000 drm/i915/skl: Restore the DDI translation tables when enabling PW1 Cc: Imre Deak <[email protected]> Cc: Daniel Vetter <[email protected]> Signed-off-by: Rodrigo Vivi <[email protected]> Reviewed-by: Imre Deak <[email protected]> [Jani: regression reference] Signed-off-by: Jani Nikula <[email protected]>
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Dmitry Vyukov reported the following using trinity and the memory error detector AddressSanitizer (https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel). [ 124.575597] ERROR: AddressSanitizer: heap-buffer-overflow on address ffff88002e280000 [ 124.576801] ffff88002e280000 is located 131938492886538 bytes to the left of 28857600-byte region [ffffffff81282e0a, ffffffff82e0830a) [ 124.578633] Accessed by thread T10915: [ 124.579295] inlined in describe_heap_address ./arch/x86/mm/asan/report.c:164 [ 124.579295] #0 ffffffff810dd277 in asan_report_error ./arch/x86/mm/asan/report.c:278 [ 124.580137] #1 ffffffff810dc6a0 in asan_check_region ./arch/x86/mm/asan/asan.c:37 [ 124.581050] #2 ffffffff810dd423 in __tsan_read8 ??:0 [ 124.581893] #3 ffffffff8107c093 in get_wchan ./arch/x86/kernel/process_64.c:444 The address checks in the 64bit implementation of get_wchan() are wrong in several ways: - The lower bound of the stack is not the start of the stack page. It's the start of the stack page plus sizeof (struct thread_info) - The upper bound must be: top_of_stack - TOP_OF_KERNEL_STACK_PADDING - 2 * sizeof(unsigned long). The 2 * sizeof(unsigned long) is required because the stack pointer points at the frame pointer. The layout on the stack is: ... IP FP ... IP FP. So we need to make sure that both IP and FP are in the bounds. Fix the bound checks and get rid of the mix of numeric constants, u64 and unsigned long. Making all unsigned long allows us to use the same function for 32bit as well. Use READ_ONCE() when accessing the stack. This does not prevent a concurrent wakeup of the task and the stack changing, but at least it avoids TOCTOU. Also check task state at the end of the loop. Again that does not prevent concurrent changes, but it avoids walking for nothing. Add proper comments while at it. Reported-by: Dmitry Vyukov <[email protected]> Reported-by: Sasha Levin <[email protected]> Based-on-patch-from: Wolfram Gloger <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Borislav Petkov <[email protected]> Reviewed-by: Dmitry Vyukov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Kostya Serebryany <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: kasan-dev <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Wolfram Gloger <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
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Commit 1a3d595 ("MIPS: Tidy up FPU context switching") removed FP context saving from the asm-written resume function in favour of reusing existing code to perform the same task. However it only removed the FP context saving code from the r4k_switch.S implementation of resume. Octeon uses its own implementation in octeon_switch.S, so remove FP context saving there too in order to prevent attempting to save context twice. That formerly led to an exception from the second save as follows because the FPU had already been disabled by the first save: do_cpu invoked from kernel context![#1]: CPU: 0 PID: 2 Comm: kthreadd Not tainted 4.3.0-rc2-dirty #2 task: 800000041f84a008 ti: 800000041f864000 task.ti: 800000041f864000 $ 0 : 0000000000000000 0000000010008ce1 0000000000100000 ffffffffbfffffff $ 4 : 800000041f84a008 800000041f84ac08 800000041f84c000 0000000000000004 $ 8 : 0000000000000001 0000000000000000 0000000000000000 0000000000000001 $12 : 0000000010008ce3 0000000000119c60 0000000000000036 800000041f864000 $16 : 800000041f84ac08 800000000792ce80 800000041f84a008 ffffffff81758b00 $20 : 0000000000000000 ffffffff8175ae50 0000000000000000 ffffffff8176c740 $24 : 0000000000000006 ffffffff81170300 $28 : 800000041f864000 800000041f867d90 0000000000000000 ffffffff815f3fa0 Hi : 0000000000fa8257 Lo : ffffffffe15cfc00 epc : ffffffff8112821c resume+0x9c/0x200 ra : ffffffff815f3fa0 __schedule+0x3f0/0x7d8 Status: 10008ce2 KX SX UX KERNEL EXL Cause : 1080002c (ExcCode 0b) PrId : 000d0601 (Cavium Octeon+) Modules linked in: Process kthreadd (pid: 2, threadinfo=800000041f864000, task=800000041f84a008, tls=0000000000000000) Stack : ffffffff81604218 ffffffff815f7e08 800000041f84a008 ffffffff811681b0 800000041f84a008 ffffffff817e9878 0000000000000000 ffffffff81770000 ffffffff81768340 ffffffff81161398 0000000000000001 0000000000000000 0000000000000000 ffffffff815f4424 0000000000000000 ffffffff81161d68 ffffffff81161be8 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ffffffff8111e16c 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ... Call Trace: [<ffffffff8112821c>] resume+0x9c/0x200 [<ffffffff815f3fa0>] __schedule+0x3f0/0x7d8 [<ffffffff815f4424>] schedule+0x34/0x98 [<ffffffff81161d68>] kthreadd+0x180/0x198 [<ffffffff8111e16c>] ret_from_kernel_thread+0x14/0x1c Tested using cavium_octeon_defconfig on an EdgeRouter Lite. Fixes: 1a3d595 ("MIPS: Tidy up FPU context switching") Reported-by: Aaro Koskinen <[email protected]> Signed-off-by: Paul Burton <[email protected]> Cc: [email protected] Cc: Aleksey Makarov <[email protected]> Cc: [email protected] Cc: Chandrakala Chavva <[email protected]> Cc: David Daney <[email protected]> Cc: Leonid Rosenboim <[email protected]> Patchwork: https://patchwork.linux-mips.org/patch/11166/ Signed-off-by: Ralf Baechle <[email protected]>
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Oct 27, 2015
My colleague ran into a program stall on a x86_64 server, where n_tty_read() was waiting for data even if there was data in the buffer in the pty. kernel stack for the stuck process looks like below. #0 [ffff88303d107b58] __schedule at ffffffff815c4b20 #1 [ffff88303d107bd0] schedule at ffffffff815c513e #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23 #5 [ffff88303d107dd0] tty_read at ffffffff81368013 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57 #8 [ffff88303d107f00] sys_read at ffffffff811a4306 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7 There seems to be two problems causing this issue. First, in drivers/tty/n_tty.c, __receive_buf() stores the data and updates ldata->commit_head using smp_store_release() and then checks the wait queue using waitqueue_active(). However, since there is no memory barrier, __receive_buf() could return without calling wake_up_interactive_poll(), and at the same time, n_tty_read() could start to wait in wait_woken() as in the following chart. __receive_buf() n_tty_read() ------------------------------------------------------------------------ if (waitqueue_active(&tty->read_wait)) /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ add_wait_queue(&tty->read_wait, &wait); ... if (!input_available_p(tty, 0)) { smp_store_release(&ldata->commit_head, ldata->read_head); ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ The second problem is that n_tty_read() also lacks a memory barrier call and could also cause __receive_buf() to return without calling wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken() as in the chart below. __receive_buf() n_tty_read() ------------------------------------------------------------------------ spin_lock_irqsave(&q->lock, flags); /* from add_wait_queue() */ ... if (!input_available_p(tty, 0)) { /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ smp_store_release(&ldata->commit_head, ldata->read_head); if (waitqueue_active(&tty->read_wait)) __add_wait_queue(q, wait); spin_unlock_irqrestore(&q->lock,flags); /* from add_wait_queue() */ ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ There are also other places in drivers/tty/n_tty.c which have similar calls to waitqueue_active(), so instead of adding many memory barrier calls, this patch simply removes the call to waitqueue_active(), leaving just wake_up*() behind. This fixes both problems because, even though the memory access before or after the spinlocks in both wake_up*() and add_wait_queue() can sneak into the critical section, it cannot go past it and the critical section assures that they will be serialized (please see "INTER-CPU ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a better explanation). Moreover, the resulting code is much simpler. Latency measurement using a ping-pong test over a pty doesn't show any visible performance drop. Signed-off-by: Kosuke Tatsukawa <[email protected]> Cc: [email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
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When running kprobe test on arm64 rt kernel, it reports the below warning: root@qemu7:~# modprobe kprobe_example BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 0, irqs_disabled(): 128, pid: 484, name: modprobe CPU: 0 PID: 484 Comm: modprobe Not tainted 4.1.6-rt5 #2 Hardware name: linux,dummy-virt (DT) Call trace: [<ffffffc0000891b8>] dump_backtrace+0x0/0x128 [<ffffffc000089300>] show_stack+0x20/0x30 [<ffffffc00061dae8>] dump_stack+0x1c/0x28 [<ffffffc0000bbad0>] ___might_sleep+0x120/0x198 [<ffffffc0006223e8>] rt_spin_lock+0x28/0x40 [<ffffffc000622b30>] __aarch64_insn_write+0x28/0x78 [<ffffffc000622e48>] aarch64_insn_patch_text_nosync+0x18/0x48 [<ffffffc000622ee8>] aarch64_insn_patch_text_cb+0x70/0xa0 [<ffffffc000622f40>] aarch64_insn_patch_text_sync+0x28/0x48 [<ffffffc0006236e0>] arch_arm_kprobe+0x38/0x48 [<ffffffc00010e6f4>] arm_kprobe+0x34/0x50 [<ffffffc000110374>] register_kprobe+0x4cc/0x5b8 [<ffffffbffc002038>] kprobe_init+0x38/0x7c [kprobe_example] [<ffffffc000084240>] do_one_initcall+0x90/0x1b0 [<ffffffc00061c498>] do_init_module+0x6c/0x1cc [<ffffffc0000fd0c0>] load_module+0x17f8/0x1db0 [<ffffffc0000fd8cc>] SyS_finit_module+0xb4/0xc8 Convert patch_lock to raw loc kto avoid this issue. Although the problem is found on rt kernel, the fix should be applicable to mainline kernel too. Acked-by: Steven Rostedt <[email protected]> Signed-off-by: Yang Shi <[email protected]> Signed-off-by: Will Deacon <[email protected]>
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When freqdomain_cpus attribute is read from an offlined cpu, it will cause crash. This change prevents calling cpufreq_show_cpus when policy driver_data is NULL. Crash info: [ 170.814949] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [ 170.814990] IP: [<ffffffff813b2490>] _find_next_bit.part.0+0x10/0x70 [ 170.815021] PGD 227d30067 PUD 229e56067 PMD 0 [ 170.815043] Oops: 0000 [#2] SMP [ 170.816022] CPU: 3 PID: 3121 Comm: cat Tainted: G D OE 4.3.0-rc3+ torvalds#33 ... ... [ 170.816657] Call Trace: [ 170.816672] [<ffffffff813b2505>] ? find_next_bit+0x15/0x20 [ 170.816696] [<ffffffff8160e47c>] cpufreq_show_cpus+0x5c/0xd0 [ 170.816722] [<ffffffffa031a409>] show_freqdomain_cpus+0x19/0x20 [acpi_cpufreq] [ 170.816749] [<ffffffff8160e65b>] show+0x3b/0x60 [ 170.816769] [<ffffffff8129b31c>] sysfs_kf_seq_show+0xbc/0x130 [ 170.816793] [<ffffffff81299be3>] kernfs_seq_show+0x23/0x30 [ 170.816816] [<ffffffff81240f2c>] seq_read+0xec/0x390 [ 170.816837] [<ffffffff8129a64a>] kernfs_fop_read+0x10a/0x160 [ 170.816861] [<ffffffff8121d9b7>] __vfs_read+0x37/0x100 [ 170.816883] [<ffffffff813217c0>] ? security_file_permission+0xa0/0xc0 [ 170.816909] [<ffffffff8121e2e3>] vfs_read+0x83/0x130 [ 170.816930] [<ffffffff8121f035>] SyS_read+0x55/0xc0 ... ... [ 170.817185] ---[ end trace bc6eadf82b2b965a ]--- Signed-off-by: Srinivas Pandruvada <[email protected]> Acked-by: Viresh Kumar <[email protected]> Cc: 4.2+ <[email protected]> # 4.2+ Signed-off-by: Rafael J. Wysocki <[email protected]>
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Nov 5, 2015
sock_i_uid(struct sock *) is being called without checking for a valid "struct sock" pointer, resulting in following Null pointer dereference: [ 17.633071] Unable to handle kernel NULL pointer dereference at virtual address 00000198 [ 17.641087] pgd = ffffffc07a554000 [ 17.644465] [00000198] *pgd=00000000fa49b003, *pud=00000000fa49b003, *pmd=0000000000000000 [ 17.652669] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 17.658186] Modules linked in: [ 17.661217] CPU: 1 PID: 1333 Comm: S21avahi-daemon Not tainted 4.0.0-rc7+ #2 [ 17.668195] Hardware name: ARM Juno development board (r0) (DT) [ 17.674055] task: ffffffc976936800 ti: ffffffc079c0c000 task.ti: ffffffc079c0c000 [ 17.681470] PC is at _raw_read_lock_bh+0x34/0x54 [ 17.686042] LR is at sock_i_uid+0x24/0x64 Not that we need to check for valid pointer everytime we call sock_i_uid() but plan is to at least do it when we are doing this Null pointer check for other arguments. Change-Id: I04521c1c38179687acd91d155ea2fd4658573ae7 Signed-off-by: Amit Pundir <[email protected]>
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Dec 21, 2015
Both non-removable and broken-cd are set for dwmmc_2. If only use 'non-removable', no sdio card detection will happen. If only use 'broken-cd', following error message will happen periodicly: [ 601.103290] INFO: task kworker/u16:1:49 blocked for more than 120 seconds. [ 601.110176] Tainted: G W 3.18.0+ #2 [ 601.115334] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 601.123165] kworker/u16:1 D ffffffc000085598 0 49 2 0x00000000 [ 601.130270] Workqueue: kmmcd mmc_rescan [ 601.134127] Call trace: [ 601.136580] [<ffffffc000085598>] __switch_to+0x74/0x8c [ 601.141722] [<ffffffc000802ba8>] __schedule+0x2b8/0x744 [ 601.146965] [<ffffffc000803058>] schedule+0x24/0x74 [ 601.151852] [<ffffffc000805bc0>] schedule_timeout+0x1b0/0x24c [ 601.157615] [<ffffffc000803d20>] wait_for_common+0x9c/0x144 [ 601.163193] [<ffffffc000803dd8>] wait_for_completion+0x10/0x1c Message from sy[ 601.169304] [<ffffffc0006517c4>] mmc_wait_for_req_done+0x34/0xfc slogd@linaro-dev[ 601.176701] [<ffffffc000651914>] mmc_wait_for_cmd+0x58/0x88 eloper at Jul 3[ 601.183658] [<ffffffc00065804c>] _mmc_select_card+0x44/0x54 18:55:31 ... [ 601.190595] [<ffffffc000658204>] mmc_select_card+0x14/0x50 kernel:[ 601.1[ 601.197478] [<ffffffc00065aba8>] mmc_sdio_alive+0xc/0x18 34127] Call trac[ 601.204174] [<ffffffc000653ba0>] _mmc_detect_card_removed+0x60/0xf8 e: [ 601.211805] [<ffffffc00065bd38>] mmc_sdio_detect+0x28/0xc4 [ 601.217732] [<ffffffc000653efc>] mmc_rescan+0x1c0/0x33c [ 601.222964] [<ffffffc0000c6d9c>] process_one_work+0x13c/0x408 [ 601.228724] [<ffffffc0000c7814>] worker_thread+0x140/0x470 [ 601.234228] [<ffffffc0000cbed8>] kthread+0xd8/0xf0 Signed-off-by: Guodong Xu <[email protected]>
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When a passive TCP is created, we eventually call tcp_md5_do_add() with sk pointing to the child. It is not owner by the user yet (we will add this socket into listener accept queue a bit later anyway) But we do own the spinlock, so amend the lockdep annotation to avoid following splat : [ 8451.090932] net/ipv4/tcp_ipv4.c:923 suspicious rcu_dereference_protected() usage! [ 8451.090932] [ 8451.090932] other info that might help us debug this: [ 8451.090932] [ 8451.090934] [ 8451.090934] rcu_scheduler_active = 1, debug_locks = 1 [ 8451.090936] 3 locks held by socket_sockopt_/214795: [ 8451.090936] #0: (rcu_read_lock){.+.+..}, at: [<ffffffff855c6ac1>] __netif_receive_skb_core+0x151/0xe90 [ 8451.090947] #1: (rcu_read_lock){.+.+..}, at: [<ffffffff85618143>] ip_local_deliver_finish+0x43/0x2b0 [ 8451.090952] #2: (slock-AF_INET){+.-...}, at: [<ffffffff855acda5>] sk_clone_lock+0x1c5/0x500 [ 8451.090958] [ 8451.090958] stack backtrace: [ 8451.090960] CPU: 7 PID: 214795 Comm: socket_sockopt_ [ 8451.091215] Call Trace: [ 8451.091216] <IRQ> [<ffffffff856fb29c>] dump_stack+0x55/0x76 [ 8451.091229] [<ffffffff85123b5b>] lockdep_rcu_suspicious+0xeb/0x110 [ 8451.091235] [<ffffffff8564544f>] tcp_md5_do_add+0x1bf/0x1e0 [ 8451.091239] [<ffffffff85645751>] tcp_v4_syn_recv_sock+0x1f1/0x4c0 [ 8451.091242] [<ffffffff85642b27>] ? tcp_v4_md5_hash_skb+0x167/0x190 [ 8451.091246] [<ffffffff85647c78>] tcp_check_req+0x3c8/0x500 [ 8451.091249] [<ffffffff856451ae>] ? tcp_v4_inbound_md5_hash+0x11e/0x190 [ 8451.091253] [<ffffffff85647170>] tcp_v4_rcv+0x3c0/0x9f0 [ 8451.091256] [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0 [ 8451.091260] [<ffffffff856181b6>] ip_local_deliver_finish+0xb6/0x2b0 [ 8451.091263] [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0 [ 8451.091267] [<ffffffff85618d38>] ip_local_deliver+0x48/0x80 [ 8451.091270] [<ffffffff85618510>] ip_rcv_finish+0x160/0x700 [ 8451.091273] [<ffffffff8561900e>] ip_rcv+0x29e/0x3d0 [ 8451.091277] [<ffffffff855c74b7>] __netif_receive_skb_core+0xb47/0xe90 Fixes: a8afca0 ("tcp: md5: protects md5sig_info with RCU") Signed-off-by: Eric Dumazet <[email protected]> Reported-by: Willem de Bruijn <[email protected]> Signed-off-by: David S. Miller <[email protected]>
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This was the second perf intr issue perf sampling on multicore requires intr to be enabled on all cores. ARC perf probe code used helper arc_request_percpu_irq() which calls - request_percpu_irq() on core0 - enable_percpu_irq() on all all cores (including core0) genirq requires that request be made ahead of enable call. However if perf probe happened on non core0 (observed on a 3.18 kernel), enable would get called ahead of request, failing obviously and rendering perf intr disabled on all such cores [ 11.120000] 1 ARC perf : 8 counters (48 bits), 113 conditions, [overflow IRQ support] [ 11.130000] 1 -----> enable_percpu_irq() IRQ 20 failed [ 11.140000] 3 -----> enable_percpu_irq() IRQ 20 failed [ 11.140000] 2 -----> enable_percpu_irq() IRQ 20 failed [ 11.140000] 0 =====> request_percpu_irq() IRQ 20 [ 11.140000] 0 -----> enable_percpu_irq() IRQ 20 Fix this fragility, by calling request_percpu_irq() on whatever core calls probe (there is no requirement on which core calls this anyways) and then calling enable on each cores. Interestingly this started as invesigation of STAR 9000838902: "sporadically IRQs enabled on perf prob" which was about occassional boot spew as request_percpu_irq got called non-locally (from an IPI), and re-enabled interrupts in following path proc_mkdir -> spin_unlock_irq() which the irq work code didn't like. | ARC perf : 8 counters (48 bits), 113 conditions, [overflow IRQ support] | | BUG: failure at ../kernel/irq_work.c:135/irq_work_run_list()! | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.18.10-01127-g285efb8e66d1 #2 | | Stack Trace: | arc_unwind_core.constprop.1+0x94/0x104 | dump_stack+0x62/0x98 | irq_work_run_list+0xb0/0xb4 | irq_work_run+0x22/0x3c | do_IPI+0x74/0x9c | handle_irq_event_percpu+0x34/0x164 | handle_percpu_irq+0x58/0x78 | generic_handle_irq+0x1e/0x2c | arch_do_IRQ+0x3c/0x60 | ret_from_exception+0x0/0x8 Cc: Marc Zyngier <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Cc: Alexey Brodkin <[email protected]> Cc: <[email protected]> #4.2+ Signed-off-by: Vineet Gupta <[email protected]>
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When using the Promise TX2+ SATA controller on PA-RISC, the system often crashes with kernel panic, for example just writing data with the dd utility will make it crash. Kernel panic - not syncing: drivers/parisc/sba_iommu.c: I/O MMU @ 000000000000a000 is out of mapping resources CPU: 0 PID: 18442 Comm: mkspadfs Not tainted 4.4.0-rc2 #2 Backtrace: [<000000004021497c>] show_stack+0x14/0x20 [<0000000040410bf0>] dump_stack+0x88/0x100 [<000000004023978c>] panic+0x124/0x360 [<0000000040452c18>] sba_alloc_range+0x698/0x6a0 [<0000000040453150>] sba_map_sg+0x260/0x5b8 [<000000000c18dbb4>] ata_qc_issue+0x264/0x4a8 [libata] [<000000000c19535c>] ata_scsi_translate+0xe4/0x220 [libata] [<000000000c19a93c>] ata_scsi_queuecmd+0xbc/0x320 [libata] [<0000000040499bbc>] scsi_dispatch_cmd+0xfc/0x130 [<000000004049da34>] scsi_request_fn+0x6e4/0x970 [<00000000403e95a8>] __blk_run_queue+0x40/0x60 [<00000000403e9d8c>] blk_run_queue+0x3c/0x68 [<000000004049a534>] scsi_run_queue+0x2a4/0x360 [<000000004049be68>] scsi_end_request+0x1a8/0x238 [<000000004049de84>] scsi_io_completion+0xfc/0x688 [<0000000040493c74>] scsi_finish_command+0x17c/0x1d0 The cause of the crash is not exhaustion of the IOMMU space, there is plenty of free pages. The function sba_alloc_range is called with size 0x11000, thus the pages_needed variable is 0x11. The function sba_search_bitmap is called with bits_wanted 0x11 and boundary size is 0x10 (because dma_get_seg_boundary(dev) returns 0xffff). The function sba_search_bitmap attempts to allocate 17 pages that must not cross 16-page boundary - it can't satisfy this requirement (iommu_is_span_boundary always returns true) and fails even if there are many free entries in the IOMMU space. How did it happen that we try to allocate 17 pages that don't cross 16-page boundary? The cause is in the function iommu_coalesce_chunks. This function tries to coalesce adjacent entries in the scatterlist. The function does several checks if it may coalesce one entry with the next, one of those checks is this: if (startsg->length + dma_len > max_seg_size) break; When it finishes coalescing adjacent entries, it allocates the mapping: sg_dma_len(contig_sg) = dma_len; dma_len = ALIGN(dma_len + dma_offset, IOVP_SIZE); sg_dma_address(contig_sg) = PIDE_FLAG | (iommu_alloc_range(ioc, dev, dma_len) << IOVP_SHIFT) | dma_offset; It is possible that (startsg->length + dma_len > max_seg_size) is false (we are just near the 0x10000 max_seg_size boundary), so the funcion decides to coalesce this entry with the next entry. When the coalescing succeeds, the function performs dma_len = ALIGN(dma_len + dma_offset, IOVP_SIZE); And now, because of non-zero dma_offset, dma_len is greater than 0x10000. iommu_alloc_range (a pointer to sba_alloc_range) is called and it attempts to allocate 17 pages for a device that must not cross 16-page boundary. To fix the bug, we must make sure that dma_len after addition of dma_offset and alignment doesn't cross the segment boundary. I.e. change if (startsg->length + dma_len > max_seg_size) break; to if (ALIGN(dma_len + dma_offset + startsg->length, IOVP_SIZE) > max_seg_size) break; This patch makes this change (it precalculates max_seg_boundary at the beginning of the function iommu_coalesce_chunks). I also added a check that the mapping length doesn't exceed dma_get_seg_boundary(dev) (it is not needed for Promise TX2+ SATA, but it may be needed for other devices that have dma_get_seg_boundary lower than dma_get_max_seg_size). Signed-off-by: Mikulas Patocka <[email protected]> Cc: [email protected] Signed-off-by: Helge Deller <[email protected]>
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When a43eec3 ("bpf: introduce bpf_perf_event_output() helper") added PERF_COUNT_SW_BPF_OUTPUT we ended up with a new entry in the event_symbols_sw array that wasn't initialized, thus set to NULL, fix print_symbol_events() to check for that case so that we don't crash if this happens again. (gdb) bt #0 __match_glob (ignore_space=false, pat=<optimized out>, str=<optimized out>) at util/string.c:198 #1 strglobmatch (str=<optimized out>, pat=pat@entry=0x7fffffffe61d "stall") at util/string.c:252 #2 0x00000000004993a5 in print_symbol_events (type=1, syms=0x872880 <event_symbols_sw+160>, max=11, name_only=false, event_glob=0x7fffffffe61d "stall") at util/parse-events.c:1615 #3 print_events (event_glob=event_glob@entry=0x7fffffffe61d "stall", name_only=false) at util/parse-events.c:1675 #4 0x000000000042c79e in cmd_list (argc=1, argv=0x7fffffffe390, prefix=<optimized out>) at builtin-list.c:68 #5 0x00000000004788a5 in run_builtin (p=p@entry=0x871758 <commands+120>, argc=argc@entry=2, argv=argv@entry=0x7fffffffe390) at perf.c:370 #6 0x0000000000420ab0 in handle_internal_command (argv=0x7fffffffe390, argc=2) at perf.c:429 #7 run_argv (argv=0x7fffffffe110, argcp=0x7fffffffe11c) at perf.c:473 #8 main (argc=2, argv=0x7fffffffe390) at perf.c:588 (gdb) p event_symbols_sw[PERF_COUNT_SW_BPF_OUTPUT] $4 = {symbol = 0x0, alias = 0x0} (gdb) A patch to robustify perf to not segfault when the next counter gets added in the kernel will follow this one. Reported-by: Ingo Molnar <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: David Ahern <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Wang Nan <[email protected]> Link: http://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When we do cat /sys/kernel/debug/tracing/printk_formats, we hit kernel panic at t_show. general protection fault: 0000 [#1] PREEMPT SMP CPU: 0 PID: 2957 Comm: sh Tainted: G W O 3.14.55-x86_64-01062-gd4acdc7 #2 RIP: 0010:[<ffffffff811375b2>] [<ffffffff811375b2>] t_show+0x22/0xe0 RSP: 0000:ffff88002b4ebe80 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004 RDX: 0000000000000004 RSI: ffffffff81fd26a6 RDI: ffff880032f9f7b1 RBP: ffff88002b4ebe98 R08: 0000000000001000 R09: 000000000000ffec R10: 0000000000000000 R11: 000000000000000f R12: ffff880004d9b6c0 R13: 7365725f6d706400 R14: ffff880004d9b6c0 R15: ffffffff82020570 FS: 0000000000000000(0000) GS:ffff88003aa00000(0063) knlGS:00000000f776bc40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f6c02ff0 CR3: 000000002c2b3000 CR4: 00000000001007f0 Call Trace: [<ffffffff811dc076>] seq_read+0x2f6/0x3e0 [<ffffffff811b749b>] vfs_read+0x9b/0x160 [<ffffffff811b7f69>] SyS_read+0x49/0xb0 [<ffffffff81a3a4b9>] ia32_do_call+0x13/0x13 ---[ end trace 5bd9eb630614861e ]--- Kernel panic - not syncing: Fatal exception When the first time find_next calls find_next_mod_format, it should iterate the trace_bprintk_fmt_list to find the first print format of the module. However in current code, start_index is smaller than *pos at first, and code will not iterate the list. Latter container_of will get the wrong address with former v, which will cause mod_fmt be a meaningless object and so is the returned mod_fmt->fmt. This patch will fix it by correcting the start_index. After fixed, when the first time calls find_next_mod_format, start_index will be equal to *pos, and code will iterate the trace_bprintk_fmt_list to get the right module printk format, so is the returned mod_fmt->fmt. Link: http://lkml.kernel.org/r/[email protected] Cc: [email protected] # 3.12+ Fixes: 102c932 "tracing: Add __tracepoint_string() to export string pointers" Signed-off-by: Qiu Peiyang <[email protected]> Signed-off-by: Steven Rostedt <[email protected]>
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commit eddd382 upstream. Dmitry Vyukov reported the following using trinity and the memory error detector AddressSanitizer (https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel). [ 124.575597] ERROR: AddressSanitizer: heap-buffer-overflow on address ffff88002e280000 [ 124.576801] ffff88002e280000 is located 131938492886538 bytes to the left of 28857600-byte region [ffffffff81282e0a, ffffffff82e0830a) [ 124.578633] Accessed by thread T10915: [ 124.579295] inlined in describe_heap_address ./arch/x86/mm/asan/report.c:164 [ 124.579295] #0 ffffffff810dd277 in asan_report_error ./arch/x86/mm/asan/report.c:278 [ 124.580137] #1 ffffffff810dc6a0 in asan_check_region ./arch/x86/mm/asan/asan.c:37 [ 124.581050] #2 ffffffff810dd423 in __tsan_read8 ??:0 [ 124.581893] #3 ffffffff8107c093 in get_wchan ./arch/x86/kernel/process_64.c:444 The address checks in the 64bit implementation of get_wchan() are wrong in several ways: - The lower bound of the stack is not the start of the stack page. It's the start of the stack page plus sizeof (struct thread_info) - The upper bound must be: top_of_stack - TOP_OF_KERNEL_STACK_PADDING - 2 * sizeof(unsigned long). The 2 * sizeof(unsigned long) is required because the stack pointer points at the frame pointer. The layout on the stack is: ... IP FP ... IP FP. So we need to make sure that both IP and FP are in the bounds. Fix the bound checks and get rid of the mix of numeric constants, u64 and unsigned long. Making all unsigned long allows us to use the same function for 32bit as well. Use READ_ONCE() when accessing the stack. This does not prevent a concurrent wakeup of the task and the stack changing, but at least it avoids TOCTOU. Also check task state at the end of the loop. Again that does not prevent concurrent changes, but it avoids walking for nothing. Add proper comments while at it. Reported-by: Dmitry Vyukov <[email protected]> Reported-by: Sasha Levin <[email protected]> Based-on-patch-from: Wolfram Gloger <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Borislav Petkov <[email protected]> Reviewed-by: Dmitry Vyukov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Kostya Serebryany <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: kasan-dev <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Wolfram Gloger <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit e81107d upstream. My colleague ran into a program stall on a x86_64 server, where n_tty_read() was waiting for data even if there was data in the buffer in the pty. kernel stack for the stuck process looks like below. #0 [ffff88303d107b58] __schedule at ffffffff815c4b20 #1 [ffff88303d107bd0] schedule at ffffffff815c513e #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23 #5 [ffff88303d107dd0] tty_read at ffffffff81368013 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57 #8 [ffff88303d107f00] sys_read at ffffffff811a4306 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7 There seems to be two problems causing this issue. First, in drivers/tty/n_tty.c, __receive_buf() stores the data and updates ldata->commit_head using smp_store_release() and then checks the wait queue using waitqueue_active(). However, since there is no memory barrier, __receive_buf() could return without calling wake_up_interactive_poll(), and at the same time, n_tty_read() could start to wait in wait_woken() as in the following chart. __receive_buf() n_tty_read() ------------------------------------------------------------------------ if (waitqueue_active(&tty->read_wait)) /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ add_wait_queue(&tty->read_wait, &wait); ... if (!input_available_p(tty, 0)) { smp_store_release(&ldata->commit_head, ldata->read_head); ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ The second problem is that n_tty_read() also lacks a memory barrier call and could also cause __receive_buf() to return without calling wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken() as in the chart below. __receive_buf() n_tty_read() ------------------------------------------------------------------------ spin_lock_irqsave(&q->lock, flags); /* from add_wait_queue() */ ... if (!input_available_p(tty, 0)) { /* Memory operations issued after the RELEASE may be completed before the RELEASE operation has completed */ smp_store_release(&ldata->commit_head, ldata->read_head); if (waitqueue_active(&tty->read_wait)) __add_wait_queue(q, wait); spin_unlock_irqrestore(&q->lock,flags); /* from add_wait_queue() */ ... timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); ------------------------------------------------------------------------ There are also other places in drivers/tty/n_tty.c which have similar calls to waitqueue_active(), so instead of adding many memory barrier calls, this patch simply removes the call to waitqueue_active(), leaving just wake_up*() behind. This fixes both problems because, even though the memory access before or after the spinlocks in both wake_up*() and add_wait_queue() can sneak into the critical section, it cannot go past it and the critical section assures that they will be serialized (please see "INTER-CPU ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a better explanation). Moreover, the resulting code is much simpler. Latency measurement using a ping-pong test over a pty doesn't show any visible performance drop. Signed-off-by: Kosuke Tatsukawa <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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…_BH() in preemptible context. [ Upstream commit 44f49dd ] Fixes the following kernel BUG : BUG: using __this_cpu_add() in preemptible [00000000] code: bash/2758 caller is __this_cpu_preempt_check+0x13/0x15 CPU: 0 PID: 2758 Comm: bash Tainted: P O 3.18.19 #2 ffffffff8170eaca ffff880110d1b788 ffffffff81482b2a 0000000000000000 0000000000000000 ffff880110d1b7b8 ffffffff812010ae ffff880007cab800 ffff88001a060800 ffff88013a899108 ffff880108b84240 ffff880110d1b7c8 Call Trace: [<ffffffff81482b2a>] dump_stack+0x52/0x80 [<ffffffff812010ae>] check_preemption_disabled+0xce/0xe1 [<ffffffff812010d4>] __this_cpu_preempt_check+0x13/0x15 [<ffffffff81419d60>] ipmr_queue_xmit+0x647/0x70c [<ffffffff8141a154>] ip_mr_forward+0x32f/0x34e [<ffffffff8141af76>] ip_mroute_setsockopt+0xe03/0x108c [<ffffffff810553fc>] ? get_parent_ip+0x11/0x42 [<ffffffff810e6974>] ? pollwake+0x4d/0x51 [<ffffffff81058ac0>] ? default_wake_function+0x0/0xf [<ffffffff810553fc>] ? get_parent_ip+0x11/0x42 [<ffffffff810613d9>] ? __wake_up_common+0x45/0x77 [<ffffffff81486ea9>] ? _raw_spin_unlock_irqrestore+0x1d/0x32 [<ffffffff810618bc>] ? __wake_up_sync_key+0x4a/0x53 [<ffffffff8139a519>] ? sock_def_readable+0x71/0x75 [<ffffffff813dd226>] do_ip_setsockopt+0x9d/0xb55 [<ffffffff81429818>] ? unix_seqpacket_sendmsg+0x3f/0x41 [<ffffffff813963fe>] ? sock_sendmsg+0x6d/0x86 [<ffffffff813959d4>] ? sockfd_lookup_light+0x12/0x5d [<ffffffff8139650a>] ? SyS_sendto+0xf3/0x11b [<ffffffff810d5738>] ? new_sync_read+0x82/0xaa [<ffffffff813ddd19>] compat_ip_setsockopt+0x3b/0x99 [<ffffffff813fb24a>] compat_raw_setsockopt+0x11/0x32 [<ffffffff81399052>] compat_sock_common_setsockopt+0x18/0x1f [<ffffffff813c4d05>] compat_SyS_setsockopt+0x1a9/0x1cf [<ffffffff813c4149>] compat_SyS_socketcall+0x180/0x1e3 [<ffffffff81488ea1>] cstar_dispatch+0x7/0x1e Signed-off-by: Ani Sinha <[email protected]> Acked-by: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit 1f9c6e1 upstream. There were several bugs here. 1) The done label was in the wrong place so we didn't copy any information out when there was no command given. 2) We were using PAGE_SIZE as the size of the buffer instead of "PAGE_SIZE - pos". 3) snprintf() returns the number of characters that would have been printed if there were enough space. If there was not enough space (and we had fixed the memory corruption bug #2) then it would result in an information leak when we do simple_read_from_buffer(). I've changed it to use scnprintf() instead. I also removed the initialization at the start of the function, because I thought it made the code a little more clear. Fixes: 5e6e3a9 ('wireless: mwifiex: initial commit for Marvell mwifiex driver') Signed-off-by: Dan Carpenter <[email protected]> Acked-by: Amitkumar Karwar <[email protected]> Signed-off-by: Kalle Valo <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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[ Upstream commit b4fe85f ] Drivers like vxlan use the recently introduced udp_tunnel_xmit_skb/udp_tunnel6_xmit_skb APIs. udp_tunnel6_xmit_skb makes use of ip6tunnel_xmit, and ip6tunnel_xmit, after sending the packet, updates the struct stats using the usual u64_stats_update_begin/end calls on this_cpu_ptr(dev->tstats). udp_tunnel_xmit_skb makes use of iptunnel_xmit, which doesn't touch tstats, so drivers like vxlan, immediately after, call iptunnel_xmit_stats, which does the same thing - calls u64_stats_update_begin/end on this_cpu_ptr(dev->tstats). While vxlan is probably fine (I don't know?), calling a similar function from, say, an unbound workqueue, on a fully preemptable kernel causes real issues: [ 188.434537] BUG: using smp_processor_id() in preemptible [00000000] code: kworker/u8:0/6 [ 188.435579] caller is debug_smp_processor_id+0x17/0x20 [ 188.435583] CPU: 0 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.6 #2 [ 188.435607] Call Trace: [ 188.435611] [<ffffffff8234e936>] dump_stack+0x4f/0x7b [ 188.435615] [<ffffffff81915f3d>] check_preemption_disabled+0x19d/0x1c0 [ 188.435619] [<ffffffff81915f77>] debug_smp_processor_id+0x17/0x20 The solution would be to protect the whole this_cpu_ptr(dev->tstats)/u64_stats_update_begin/end blocks with disabling preemption and then reenabling it. Signed-off-by: Jason A. Donenfeld <[email protected]> Acked-by: Hannes Frederic Sowa <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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[ Upstream commit 1b8e6a0 ] When a passive TCP is created, we eventually call tcp_md5_do_add() with sk pointing to the child. It is not owner by the user yet (we will add this socket into listener accept queue a bit later anyway) But we do own the spinlock, so amend the lockdep annotation to avoid following splat : [ 8451.090932] net/ipv4/tcp_ipv4.c:923 suspicious rcu_dereference_protected() usage! [ 8451.090932] [ 8451.090932] other info that might help us debug this: [ 8451.090932] [ 8451.090934] [ 8451.090934] rcu_scheduler_active = 1, debug_locks = 1 [ 8451.090936] 3 locks held by socket_sockopt_/214795: [ 8451.090936] #0: (rcu_read_lock){.+.+..}, at: [<ffffffff855c6ac1>] __netif_receive_skb_core+0x151/0xe90 [ 8451.090947] #1: (rcu_read_lock){.+.+..}, at: [<ffffffff85618143>] ip_local_deliver_finish+0x43/0x2b0 [ 8451.090952] #2: (slock-AF_INET){+.-...}, at: [<ffffffff855acda5>] sk_clone_lock+0x1c5/0x500 [ 8451.090958] [ 8451.090958] stack backtrace: [ 8451.090960] CPU: 7 PID: 214795 Comm: socket_sockopt_ [ 8451.091215] Call Trace: [ 8451.091216] <IRQ> [<ffffffff856fb29c>] dump_stack+0x55/0x76 [ 8451.091229] [<ffffffff85123b5b>] lockdep_rcu_suspicious+0xeb/0x110 [ 8451.091235] [<ffffffff8564544f>] tcp_md5_do_add+0x1bf/0x1e0 [ 8451.091239] [<ffffffff85645751>] tcp_v4_syn_recv_sock+0x1f1/0x4c0 [ 8451.091242] [<ffffffff85642b27>] ? tcp_v4_md5_hash_skb+0x167/0x190 [ 8451.091246] [<ffffffff85647c78>] tcp_check_req+0x3c8/0x500 [ 8451.091249] [<ffffffff856451ae>] ? tcp_v4_inbound_md5_hash+0x11e/0x190 [ 8451.091253] [<ffffffff85647170>] tcp_v4_rcv+0x3c0/0x9f0 [ 8451.091256] [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0 [ 8451.091260] [<ffffffff856181b6>] ip_local_deliver_finish+0xb6/0x2b0 [ 8451.091263] [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0 [ 8451.091267] [<ffffffff85618d38>] ip_local_deliver+0x48/0x80 [ 8451.091270] [<ffffffff85618510>] ip_rcv_finish+0x160/0x700 [ 8451.091273] [<ffffffff8561900e>] ip_rcv+0x29e/0x3d0 [ 8451.091277] [<ffffffff855c74b7>] __netif_receive_skb_core+0xb47/0xe90 Fixes: a8afca0 ("tcp: md5: protects md5sig_info with RCU") Signed-off-by: Eric Dumazet <[email protected]> Reported-by: Willem de Bruijn <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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A recent change to the cpu_cooling code introduced a AB-BA deadlock scenario between the cpufreq_policy_notifier_list rwsem and the cooling_cpufreq_lock. This is caused by cooling_cpufreq_lock being held before the registration/removal of the notifier block (an operation which takes the rwsem), and the notifier code itself which takes the locks in the reverse order: ====================================================== [ INFO: possible circular locking dependency detected ] 3.18.0+ #1453 Not tainted ------------------------------------------------------- rc.local/770 is trying to acquire lock: (cooling_cpufreq_lock){+.+.+.}, at: [<c04abfc4>] cpufreq_thermal_notifier+0x34/0xfc but task is already holding lock: ((cpufreq_policy_notifier_list).rwsem){++++.+}, at: [<c0042f04>] __blocking_notifier_call_chain+0x34/0x68 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 ((cpufreq_policy_notifier_list).rwsem){++++.+}: [<c06bc3b0>] down_write+0x44/0x9c [<c0043444>] blocking_notifier_chain_register+0x28/0xd8 [<c04ad610>] cpufreq_register_notifier+0x68/0x90 [<c04abe4c>] __cpufreq_cooling_register.part.1+0x120/0x180 [<c04abf44>] __cpufreq_cooling_register+0x98/0xa4 [<c04abf8c>] cpufreq_cooling_register+0x18/0x1c [<bf0046f8>] imx_thermal_probe+0x1c0/0x470 [imx_thermal] [<c037cef8>] platform_drv_probe+0x50/0xac [<c037b710>] driver_probe_device+0x114/0x234 [<c037b8cc>] __driver_attach+0x9c/0xa0 [<c0379d68>] bus_for_each_dev+0x5c/0x90 [<c037b204>] driver_attach+0x24/0x28 [<c037ae7c>] bus_add_driver+0xe0/0x1d8 [<c037c0cc>] driver_register+0x80/0xfc [<c037cd80>] __platform_driver_register+0x50/0x64 [<bf007018>] 0xbf007018 [<c0008a5c>] do_one_initcall+0x88/0x1d8 [<c0095da4>] load_module+0x1768/0x1ef8 [<c0096614>] SyS_init_module+0xe0/0xf4 [<c000ec00>] ret_fast_syscall+0x0/0x48 -> #0 (cooling_cpufreq_lock){+.+.+.}: [<c00619f8>] lock_acquire+0xb0/0x124 [<c06ba3b4>] mutex_lock_nested+0x5c/0x3d8 [<c04abfc4>] cpufreq_thermal_notifier+0x34/0xfc [<c0042bf4>] notifier_call_chain+0x4c/0x8c [<c0042f20>] __blocking_notifier_call_chain+0x50/0x68 [<c0042f58>] blocking_notifier_call_chain+0x20/0x28 [<c04ae62c>] cpufreq_set_policy+0x7c/0x1d0 [<c04af3cc>] store_scaling_governor+0x74/0x9c [<c04ad418>] store+0x90/0xc0 [<c0175384>] sysfs_kf_write+0x54/0x58 [<c01746b4>] kernfs_fop_write+0xdc/0x190 [<c010dcc0>] vfs_write+0xac/0x1b4 [<c010dfec>] SyS_write+0x44/0x90 [<c000ec00>] ret_fast_syscall+0x0/0x48 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((cpufreq_policy_notifier_list).rwsem); lock(cooling_cpufreq_lock); lock((cpufreq_policy_notifier_list).rwsem); lock(cooling_cpufreq_lock); *** DEADLOCK *** 7 locks held by rc.local/770: #0: (sb_writers#6){.+.+.+}, at: [<c010dda0>] vfs_write+0x18c/0x1b4 #1: (&of->mutex){+.+.+.}, at: [<c0174678>] kernfs_fop_write+0xa0/0x190 #2: (s_active#52){.+.+.+}, at: [<c0174680>] kernfs_fop_write+0xa8/0x190 #3: (cpu_hotplug.lock){++++++}, at: [<c0026a60>] get_online_cpus+0x34/0x90 #4: (cpufreq_rwsem){.+.+.+}, at: [<c04ad3e0>] store+0x58/0xc0 #5: (&policy->rwsem){+.+.+.}, at: [<c04ad3f8>] store+0x70/0xc0 #6: ((cpufreq_policy_notifier_list).rwsem){++++.+}, at: [<c0042f04>] __blocking_notifier_call_chain+0x34/0x68 stack backtrace: CPU: 0 PID: 770 Comm: rc.local Not tainted 3.18.0+ #1453 Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) Backtrace: [<c00121c8>] (dump_backtrace) from [<c0012360>] (show_stack+0x18/0x1c) r6:c0b85a80 r5:c0b75630 r4:00000000 r3:00000000 [<c0012348>] (show_stack) from [<c06b6c48>] (dump_stack+0x7c/0x98) [<c06b6bcc>] (dump_stack) from [<c06b42a4>] (print_circular_bug+0x28c/0x2d8) r4:c0b85a80 r3:d0071d40 [<c06b4018>] (print_circular_bug) from [<c00613b0>] (__lock_acquire+0x1acc/0x1bb0) r10:c0b50660 r8:c09e6d80 r7:d0071d40 r6:c11d0f0c r5:00000007 r4:d0072240 [<c005f8e4>] (__lock_acquire) from [<c00619f8>] (lock_acquire+0xb0/0x124) r10:00000000 r9:c04abfc4 r8:00000000 r7:00000000 r6:00000000 r5:c0a06f0c r4:00000000 [<c0061948>] (lock_acquire) from [<c06ba3b4>] (mutex_lock_nested+0x5c/0x3d8) r10:ec853800 r9:c0a06ed4 r8:d0071d40 r7:c0a06ed4 r6:c11d0f0c r5:00000000 r4:c04abfc4 [<c06ba358>] (mutex_lock_nested) from [<c04abfc4>] (cpufreq_thermal_notifier+0x34/0xfc) r10:ec853800 r9:ec85380c r8:d00d7d3c r7:c0a06ed4 r6:d00d7d3c r5:00000000 r4:fffffffe [<c04abf90>] (cpufreq_thermal_notifier) from [<c0042bf4>] (notifier_call_chain+0x4c/0x8c) r7:00000000 r6:00000000 r5:00000000 r4:fffffffe [<c0042ba8>] (notifier_call_chain) from [<c0042f20>] (__blocking_notifier_call_chain+0x50/0x68) r8:c0a072a4 r7:00000000 r6:d00d7d3c r5:ffffffff r4:c0a06fc8 r3:ffffffff [<c0042ed0>] (__blocking_notifier_call_chain) from [<c0042f58>] (blocking_notifier_call_chain+0x20/0x28) r7:ec98b540 r6:c13ebc80 r5:ed76e600 r4:d00d7d3c [<c0042f38>] (blocking_notifier_call_chain) from [<c04ae62c>] (cpufreq_set_policy+0x7c/0x1d0) [<c04ae5b0>] (cpufreq_set_policy) from [<c04af3cc>] (store_scaling_governor+0x74/0x9c) r7:ec98b540 r6:0000000c r5:ec98b540 r4:ed76e600 [<c04af358>] (store_scaling_governor) from [<c04ad418>] (store+0x90/0xc0) r6:0000000c r5:ed76e6d4 r4:ed76e600 [<c04ad388>] (store) from [<c0175384>] (sysfs_kf_write+0x54/0x58) r8:0000000c r7:d00d7f78 r6:ec98b540 r5:0000000c r4:ec853800 r3:0000000c [<c0175330>] (sysfs_kf_write) from [<c01746b4>] (kernfs_fop_write+0xdc/0x190) r6:ec98b540 r5:00000000 r4:00000000 r3:c0175330 [<c01745d8>] (kernfs_fop_write) from [<c010dcc0>] (vfs_write+0xac/0x1b4) r10:0162aa70 r9:d00d6000 r8:0000000c r7:d00d7f78 r6:0162aa70 r5:0000000c r4:eccde500 [<c010dc14>] (vfs_write) from [<c010dfec>] (SyS_write+0x44/0x90) r10:0162aa70 r8:0000000c r7:eccde500 r6:eccde500 r5:00000000 r4:00000000 [<c010dfa8>] (SyS_write) from [<c000ec00>] (ret_fast_syscall+0x0/0x48) r10:00000000 r8:c000edc4 r7:00000004 r6:000216cc r5:0000000c r4:0162aa70 Solve this by moving to finer grained locking - use one mutex to protect the cpufreq_dev_list as a whole, and a separate lock to ensure correct ordering of cpufreq notifier registration and removal. cooling_list_lock is taken within cooling_cpufreq_lock on (un)registration to preserve the behavior of the code, i.e. to atomically add/remove to the list and (un)register the notifier. Fixes: 2dcd851 ("thermal: cpu_cooling: Update always cpufreq policy with Reviewed-by: Viresh Kumar <[email protected]> Signed-off-by: Russell King <[email protected]> Signed-off-by: Viresh Kumar <[email protected]> Signed-off-by: Eduardo Valentin <[email protected]>
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During genpd_poweron, genpd->lock is acquired recursively for each parent (master) domain, which are separate objects. This confuses lockdep, which considers every operation on genpd->lock as being done on the same lock class. This leads to the following false positive warning: ============================================= [ INFO: possible recursive locking detected ] 4.4.0-rc4-xu3s torvalds#32 Not tainted --------------------------------------------- swapper/0/1 is trying to acquire lock: (&genpd->lock){+.+...}, at: [<c0361550>] __genpd_poweron+0x64/0x108 but task is already holding lock: (&genpd->lock){+.+...}, at: [<c0361af8>] genpd_dev_pm_attach+0x168/0x1b8 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&genpd->lock); lock(&genpd->lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by swapper/0/1: #0: (&dev->mutex){......}, at: [<c0350910>] __driver_attach+0x48/0x98 #1: (&dev->mutex){......}, at: [<c0350920>] __driver_attach+0x58/0x98 #2: (&genpd->lock){+.+...}, at: [<c0361af8>] genpd_dev_pm_attach+0x168/0x1b8 stack backtrace: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.0-rc4-xu3s torvalds#32 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [<c0016c98>] (unwind_backtrace) from [<c00139c4>] (show_stack+0x10/0x14) [<c00139c4>] (show_stack) from [<c0270df0>] (dump_stack+0x84/0xc4) [<c0270df0>] (dump_stack) from [<c00780b8>] (__lock_acquire+0x1f88/0x215c) [<c00780b8>] (__lock_acquire) from [<c007886c>] (lock_acquire+0xa4/0xd0) [<c007886c>] (lock_acquire) from [<c0641f2c>] (mutex_lock_nested+0x70/0x4d4) [<c0641f2c>] (mutex_lock_nested) from [<c0361550>] (__genpd_poweron+0x64/0x108) [<c0361550>] (__genpd_poweron) from [<c0361b00>] (genpd_dev_pm_attach+0x170/0x1b8) [<c0361b00>] (genpd_dev_pm_attach) from [<c03520a8>] (platform_drv_probe+0x2c/0xac) [<c03520a8>] (platform_drv_probe) from [<c03507d4>] (driver_probe_device+0x208/0x2fc) [<c03507d4>] (driver_probe_device) from [<c035095c>] (__driver_attach+0x94/0x98) [<c035095c>] (__driver_attach) from [<c034ec14>] (bus_for_each_dev+0x68/0x9c) [<c034ec14>] (bus_for_each_dev) from [<c034fec8>] (bus_add_driver+0x1a0/0x218) [<c034fec8>] (bus_add_driver) from [<c035115c>] (driver_register+0x78/0xf8) [<c035115c>] (driver_register) from [<c0338488>] (exynos_drm_register_drivers+0x28/0x74) [<c0338488>] (exynos_drm_register_drivers) from [<c0338594>] (exynos_drm_init+0x6c/0xc4) [<c0338594>] (exynos_drm_init) from [<c00097f4>] (do_one_initcall+0x90/0x1dc) [<c00097f4>] (do_one_initcall) from [<c0895e08>] (kernel_init_freeable+0x158/0x1f8) [<c0895e08>] (kernel_init_freeable) from [<c063ecac>] (kernel_init+0x8/0xe8) [<c063ecac>] (kernel_init) from [<c000f7d0>] (ret_from_fork+0x14/0x24) This patch replaces mutex_lock with mutex_lock_nested() and uses recursion depth to annotate each genpd->lock operation with separate lockdep subclass. Reported-by: Anand Moon <[email protected]> Signed-off-by: Marek Szyprowski <[email protected]> Tested-by: Anand Moon <[email protected]> Tested-by: Tobias Jakobi <[email protected]> Acked-by: Ulf Hansson <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
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Calling apply_to_page_range with an empty range results in a BUG_ON from the core code. This can be triggered by trying to load the st_drv module with CONFIG_DEBUG_SET_MODULE_RONX enabled: kernel BUG at mm/memory.c:1874! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 Hardware name: ARM Juno development board (r0) (DT) task: ffffffc9763b8000 ti: ffffffc975af8000 task.ti: ffffffc975af8000 PC is at apply_to_page_range+0x2cc/0x2d0 LR is at change_memory_common+0x80/0x108 This patch fixes the issue by making change_memory_common (called by the set_memory_* functions) a NOP when numpages == 0, therefore avoiding the erroneous call to apply_to_page_range and bringing us into line with x86 and s390. Cc: <[email protected]> Reviewed-by: Laura Abbott <[email protected]> Acked-by: David Rientjes <[email protected]> Signed-off-by: Mika Penttilä <[email protected]> Signed-off-by: Will Deacon <[email protected]>
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Commit 4b4b451 ("arm/arm64: KVM: Rework the arch timer to use level-triggered semantics") brought the virtual architected timer closer to the VGIC. There is one occasion were we don't properly check for the VGIC actually having been initialized before, but instead go on to check the active state of some IRQ number. If userland hasn't instantiated a virtual GIC, we end up with a kernel NULL pointer dereference: ========= Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ffffffc9745c5000 [00000000] *pgd=00000009f631e003, *pud=00000009f631e003, *pmd=0000000000000000 Internal error: Oops: 96000006 [#2] PREEMPT SMP Modules linked in: CPU: 0 PID: 2144 Comm: kvm_simplest-ar Tainted: G D 4.5.0-rc2+ #1300 Hardware name: ARM Juno development board (r1) (DT) task: ffffffc976da8000 ti: ffffffc976e28000 task.ti: ffffffc976e28000 PC is at vgic_bitmap_get_irq_val+0x78/0x90 LR is at kvm_vgic_map_is_active+0xac/0xc8 pc : [<ffffffc0000b7e28>] lr : [<ffffffc0000b972c>] pstate: 20000145 .... ========= Fix this by bailing out early of kvm_timer_flush_hwstate() if we don't have a VGIC at all. Reported-by: Cosmin Gorgovan <[email protected]> Acked-by: Marc Zyngier <[email protected]> Signed-off-by: Andre Przywara <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Cc: <[email protected]> # 4.4.x
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…l/git/vgupta/arc Pull ARC fixes from Vineet Gupta: "I've been sitting on some of these fixes for a while. - Corner case of returning to delay slot from interrupt - Changing default interrupt prioiry level - Kconfig'ize support for super pages - Other minor fixes" * tag 'arc-4.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARC: mm: Introduce explicit super page size support ARCv2: intc: Allow interruption by lowest priority interrupt ARCv2: Check for LL-SC livelock only if LLSC is enabled ARC: shrink cpuinfo by not saving full timer BCR ARCv2: clocksource: Rename GRTC -> GFRC ... ARCv2: STAR 9000950267: Handle return from intr to Delay Slot #2
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When slub_debug alloc_calls_show is enabled we will try to track location and user of slab object on each online node, kmem_cache_node structure and cpu_cache/cpu_slub shouldn't be freed till there is the last reference to sysfs file. This fixes the following panic: BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 IP: list_locations+0x169/0x4e0 PGD 257304067 PUD 438456067 PMD 0 Oops: 0000 [#1] SMP CPU: 3 PID: 973074 Comm: cat ve: 0 Not tainted 3.10.0-229.7.2.ovz.9.30-00007-japdoll-dirty #2 9.30 Hardware name: DEPO Computers To Be Filled By O.E.M./H67DE3, BIOS L1.60c 07/14/2011 task: ffff88042a5dc5b0 ti: ffff88037f8d8000 task.ti: ffff88037f8d8000 RIP: list_locations+0x169/0x4e0 Call Trace: alloc_calls_show+0x1d/0x30 slab_attr_show+0x1b/0x30 sysfs_read_file+0x9a/0x1a0 vfs_read+0x9c/0x170 SyS_read+0x58/0xb0 system_call_fastpath+0x16/0x1b Code: 5e 07 12 00 b9 00 04 00 00 3d 00 04 00 00 0f 4f c1 3d 00 04 00 00 89 45 b0 0f 84 c3 00 00 00 48 63 45 b0 49 8b 9c c4 f8 00 00 00 <48> 8b 43 20 48 85 c0 74 b6 48 89 df e8 46 37 44 00 48 8b 53 10 CR2: 0000000000000020 Separated __kmem_cache_release from __kmem_cache_shutdown which now called on slab_kmem_cache_release (after the last reference to sysfs file object has dropped). Reintroduced locking in free_partial as sysfs file might access cache's partial list after shutdowning - partial revert of the commit 69cb8e6 ("slub: free slabs without holding locks"). Zap __remove_partial and use remove_partial (w/o underscores) as free_partial now takes list_lock which s partial revert for commit 1e4dd94 ("slub: do not assert not having lock in removing freed partial") Signed-off-by: Dmitry Safonov <[email protected]> Suggested-by: Vladimir Davydov <[email protected]> Acked-by: Vladimir Davydov <[email protected]> Cc: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
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commit e2c8b87 moved modeset locking inside resume/suspend functions, but missed a code path only executed on lid close/open on older hardware. The result was a deadlock when closing and opening the lid without suspending on such hardware: ============================================= [ INFO: possible recursive locking detected ] 4.6.0-rc1 torvalds#385 Not tainted --------------------------------------------- kworker/0:3/88 is trying to acquire lock: (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa063e6a4>] intel_display_resume+0x4a/0x12f [i915] but task is already holding lock: (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa02d0d4f>] drm_modeset_lock_all+0x3e/0xa6 [drm] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dev->mode_config.mutex); lock(&dev->mode_config.mutex); *** DEADLOCK *** May be due to missing lock nesting notation 7 locks held by kworker/0:3/88: #0: ("kacpi_notify"){++++.+}, at: [<ffffffff81068dfc>] process_one_work+0x14a/0x50b #1: ((&dpc->work)#2){+.+.+.}, at: [<ffffffff81068dfc>] process_one_work+0x14a/0x50b #2: ((acpi_lid_notifier).rwsem){++++.+}, at: [<ffffffff8106f874>] __blocking_notifier_call_chain+0x34/0x65 #3: (&dev_priv->modeset_restore_lock){+.+.+.}, at: [<ffffffffa0664cf6>] intel_lid_notify+0x3c/0xd9 [i915] #4: (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa02d0d4f>] drm_modeset_lock_all+0x3e/0xa6 [drm] #5: (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffa02d0d59>] drm_modeset_lock_all+0x48/0xa6 [drm] #6: (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffa02d0b2a>] modeset_lock+0x13c/0x1cd [drm] stack backtrace: CPU: 0 PID: 88 Comm: kworker/0:3 Not tainted 4.6.0-rc1 torvalds#385 Hardware name: LENOVO 2776LEG/2776LEG, BIOS 6EET55WW (3.15 ) 12/19/2011 Workqueue: kacpi_notify acpi_os_execute_deferred 0000000000000000 ffff88022fd5f990 ffffffff8124af06 ffffffff825b39c0 ffffffff825b39c0 ffff88022fd5fa60 ffffffff8108f547 ffff88022fd5fa70 000000008108e817 ffff880230236cc0 0000000000000000 ffffffff825b39c0 Call Trace: [<ffffffff8124af06>] dump_stack+0x67/0x90 [<ffffffff8108f547>] __lock_acquire+0xdb5/0xf71 [<ffffffff8108bd2c>] ? look_up_lock_class+0xbe/0x10a [<ffffffff8108fae2>] lock_acquire+0x137/0x1cb [<ffffffff8108fae2>] ? lock_acquire+0x137/0x1cb [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915] [<ffffffff8148202f>] mutex_lock_nested+0x7e/0x3a4 [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915] [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915] [<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm] [<ffffffffa063e6a4>] intel_display_resume+0x4a/0x12f [i915] [<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915] [<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm] [<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm] [<ffffffffa02d0bf7>] ? drm_modeset_lock+0x17/0x24 [drm] [<ffffffffa02d0c8b>] ? drm_modeset_lock_all_ctx+0x87/0xa1 [drm] [<ffffffffa0664d6a>] intel_lid_notify+0xb0/0xd9 [i915] [<ffffffff8106f4c6>] notifier_call_chain+0x4a/0x6c [<ffffffff8106f88d>] __blocking_notifier_call_chain+0x4d/0x65 [<ffffffff8106f8b9>] blocking_notifier_call_chain+0x14/0x16 [<ffffffffa0011215>] acpi_lid_send_state+0x83/0xad [button] [<ffffffffa00112a6>] acpi_button_notify+0x41/0x132 [button] [<ffffffff812b07df>] acpi_device_notify+0x19/0x1b [<ffffffff812c8570>] acpi_ev_notify_dispatch+0x49/0x64 [<ffffffff812ab9fb>] acpi_os_execute_deferred+0x14/0x20 [<ffffffff81068f17>] process_one_work+0x265/0x50b [<ffffffff810696f5>] worker_thread+0x1fc/0x2dd [<ffffffff810694f9>] ? rescuer_thread+0x309/0x309 [<ffffffff810694f9>] ? rescuer_thread+0x309/0x309 [<ffffffff8106e2d6>] kthread+0xe0/0xe8 [<ffffffff8107bc47>] ? local_clock+0x19/0x22 [<ffffffff81484f42>] ret_from_fork+0x22/0x40 [<ffffffff8106e1f6>] ? kthread_create_on_node+0x1b5/0x1b5 Fixes: e2c8b87 ("drm/i915: Use atomic helpers for suspend, v2.") Cc: Maarten Lankhorst <[email protected]> Signed-off-by: Bjørn Mork <[email protected]> Signed-off-by: Maarten Lankhorst <[email protected]> Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
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commit 3d5fe03 upstream. We can end up allocating a new compression stream with GFP_KERNEL from within the IO path, which may result is nested (recursive) IO operations. That can introduce problems if the IO path in question is a reclaimer, holding some locks that will deadlock nested IOs. Allocate streams and working memory using GFP_NOIO flag, forbidding recursive IO and FS operations. An example: inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage. git/20158 [HC0[0]:SC0[0]:HE1:SE1] takes: (jbd2_handle){+.+.?.}, at: start_this_handle+0x4ca/0x555 {IN-RECLAIM_FS-W} state was registered at: __lock_acquire+0x8da/0x117b lock_acquire+0x10c/0x1a7 start_this_handle+0x52d/0x555 jbd2__journal_start+0xb4/0x237 __ext4_journal_start_sb+0x108/0x17e ext4_dirty_inode+0x32/0x61 __mark_inode_dirty+0x16b/0x60c iput+0x11e/0x274 __dentry_kill+0x148/0x1b8 shrink_dentry_list+0x274/0x44a prune_dcache_sb+0x4a/0x55 super_cache_scan+0xfc/0x176 shrink_slab.part.14.constprop.25+0x2a2/0x4d3 shrink_zone+0x74/0x140 kswapd+0x6b7/0x930 kthread+0x107/0x10f ret_from_fork+0x3f/0x70 irq event stamp: 138297 hardirqs last enabled at (138297): debug_check_no_locks_freed+0x113/0x12f hardirqs last disabled at (138296): debug_check_no_locks_freed+0x33/0x12f softirqs last enabled at (137818): __do_softirq+0x2d3/0x3e9 softirqs last disabled at (137813): irq_exit+0x41/0x95 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(jbd2_handle); <Interrupt> lock(jbd2_handle); *** DEADLOCK *** 5 locks held by git/20158: #0: (sb_writers#7){.+.+.+}, at: [<ffffffff81155411>] mnt_want_write+0x24/0x4b #1: (&type->i_mutex_dir_key#2/1){+.+.+.}, at: [<ffffffff81145087>] lock_rename+0xd9/0xe3 #2: (&sb->s_type->i_mutex_key#11){+.+.+.}, at: [<ffffffff8114f8e2>] lock_two_nondirectories+0x3f/0x6b #3: (&sb->s_type->i_mutex_key#11/4){+.+.+.}, at: [<ffffffff8114f909>] lock_two_nondirectories+0x66/0x6b #4: (jbd2_handle){+.+.?.}, at: [<ffffffff811e31db>] start_this_handle+0x4ca/0x555 stack backtrace: CPU: 2 PID: 20158 Comm: git Not tainted 4.1.0-rc7-next-20150615-dbg-00016-g8bdf555-dirty torvalds#211 Call Trace: dump_stack+0x4c/0x6e mark_lock+0x384/0x56d mark_held_locks+0x5f/0x76 lockdep_trace_alloc+0xb2/0xb5 kmem_cache_alloc_trace+0x32/0x1e2 zcomp_strm_alloc+0x25/0x73 [zram] zcomp_strm_multi_find+0xe7/0x173 [zram] zcomp_strm_find+0xc/0xe [zram] zram_bvec_rw+0x2ca/0x7e0 [zram] zram_make_request+0x1fa/0x301 [zram] generic_make_request+0x9c/0xdb submit_bio+0xf7/0x120 ext4_io_submit+0x2e/0x43 ext4_bio_write_page+0x1b7/0x300 mpage_submit_page+0x60/0x77 mpage_map_and_submit_buffers+0x10f/0x21d ext4_writepages+0xc8c/0xe1b do_writepages+0x23/0x2c __filemap_fdatawrite_range+0x84/0x8b filemap_flush+0x1c/0x1e ext4_alloc_da_blocks+0xb8/0x117 ext4_rename+0x132/0x6dc ? mark_held_locks+0x5f/0x76 ext4_rename2+0x29/0x2b vfs_rename+0x540/0x636 SyS_renameat2+0x359/0x44d SyS_rename+0x1e/0x20 entry_SYSCALL_64_fastpath+0x12/0x6f [[email protected]: add stable mark] Signed-off-by: Sergey Senozhatsky <[email protected]> Acked-by: Minchan Kim <[email protected]> Cc: Kyeongdon Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit ec183d2 upstream. Fixes segmentation fault using, for instance: (gdb) run record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Starting program: /home/acme/bin/perf record -I -e intel_pt/tsc=1,noretcomp=1/u /bin/ls Missing separate debuginfos, use: dnf debuginfo-install glibc-2.22-7.fc23.x86_64 [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib64/libthread_db.so.1". Program received signal SIGSEGV, Segmentation fault. 0 x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 (gdb) bt #0 0x00000000004b9ea5 in tracepoint_error (e=0x0, err=13, sys=0x19b1370 "sched", name=0x19a5d00 "sched_switch") at util/parse-events.c:410 #1 0x00000000004b9fc5 in add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:433 #2 0x00000000004ba334 in add_tracepoint_event (list=0x19a5d20, idx=0x7fffffffb8c0, sys_name=0x19b1370 "sched", evt_name=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:498 #3 0x00000000004bb699 in parse_events_add_tracepoint (list=0x19a5d20, idx=0x7fffffffb8c0, sys=0x19b1370 "sched", event=0x19a5d00 "sched_switch", err=0x0, head_config=0x0) at util/parse-events.c:936 #4 0x00000000004f6eda in parse_events_parse (_data=0x7fffffffb8b0, scanner=0x19a49d0) at util/parse-events.y:391 #5 0x00000000004bc8e5 in parse_events__scanner (str=0x663ff2 "sched:sched_switch", data=0x7fffffffb8b0, start_token=258) at util/parse-events.c:1361 #6 0x00000000004bca57 in parse_events (evlist=0x19a5220, str=0x663ff2 "sched:sched_switch", err=0x0) at util/parse-events.c:1401 #7 0x0000000000518d5f in perf_evlist__can_select_event (evlist=0x19a3b90, str=0x663ff2 "sched:sched_switch") at util/record.c:253 #8 0x0000000000553c42 in intel_pt_track_switches (evlist=0x19a3b90) at arch/x86/util/intel-pt.c:364 #9 0x00000000005549d1 in intel_pt_recording_options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at arch/x86/util/intel-pt.c:664 #10 0x000000000051e076 in auxtrace_record__options (itr=0x19a2c40, evlist=0x19a3b90, opts=0x8edf68 <record+232>) at util/auxtrace.c:539 #11 0x0000000000433368 in cmd_record (argc=1, argv=0x7fffffffde60, prefix=0x0) at builtin-record.c:1264 #12 0x000000000049bec2 in run_builtin (p=0x8fa2a8 <commands+168>, argc=5, argv=0x7fffffffde60) at perf.c:390 #13 0x000000000049c12a in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:451 torvalds#14 0x000000000049c278 in run_argv (argcp=0x7fffffffdcbc, argv=0x7fffffffdcb0) at perf.c:495 torvalds#15 0x000000000049c60a in main (argc=5, argv=0x7fffffffde60) at perf.c:618 (gdb) Intel PT attempts to find the sched:sched_switch tracepoint but that seg faults if tracefs is not readable, because the error reporting structure is null, as errors are not reported when automatically adding tracepoints. Fix by checking before using. Committer note: This doesn't take place in a kernel that supports perf_event_attr.context_switch, that is the default way that will be used for tracking context switches, only in older kernels, like 4.2, in a machine with Intel PT (e.g. Broadwell) for non-priviledged users. Further info from a similar patch by Wang: The error is in tracepoint_error: it assumes the 'e' parameter is valid. However, there are many situation a parse_event() can be called without parse_events_error. See result of $ grep 'parse_events(.*NULL)' ./tools/perf/ -r' Signed-off-by: Adrian Hunter <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Tong Zhang <[email protected]> Cc: Wang Nan <[email protected]> Fixes: 1965817 ("perf tools: Enhance parsing events tracepoint error output") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit 00cd29b upstream. The starting node for a klist iteration is often passed in from somewhere way above the klist infrastructure, meaning there's no guarantee the node is still on the list. We've seen this in SCSI where we use bus_find_device() to iterate through a list of devices. In the face of heavy hotplug activity, the last device returned by bus_find_device() can be removed before the next call. This leads to Dec 3 13:22:02 localhost kernel: WARNING: CPU: 2 PID: 28073 at include/linux/kref.h:47 klist_iter_init_node+0x3d/0x50() Dec 3 13:22:02 localhost kernel: Modules linked in: scsi_debug x86_pkg_temp_thermal kvm_intel kvm irqbypass crc32c_intel joydev iTCO_wdt dcdbas ipmi_devintf acpi_power_meter iTCO_vendor_support ipmi_si imsghandler pcspkr wmi acpi_cpufreq tpm_tis tpm shpchp lpc_ich mfd_core nfsd nfs_acl lockd grace sunrpc tg3 ptp pps_core Dec 3 13:22:02 localhost kernel: CPU: 2 PID: 28073 Comm: cat Not tainted 4.4.0-rc1+ #2 Dec 3 13:22:02 localhost kernel: Hardware name: Dell Inc. PowerEdge R320/08VT7V, BIOS 2.0.22 11/19/2013 Dec 3 13:22:02 localhost kernel: ffffffff81a20e77 ffff880613acfd18 ffffffff81321eef 0000000000000000 Dec 3 13:22:02 localhost kernel: ffff880613acfd50 ffffffff8107ca52 ffff88061176b198 0000000000000000 Dec 3 13:22:02 localhost kernel: ffffffff814542b0 ffff880610cfb100 ffff88061176b198 ffff880613acfd60 Dec 3 13:22:02 localhost kernel: Call Trace: Dec 3 13:22:02 localhost kernel: [<ffffffff81321eef>] dump_stack+0x44/0x55 Dec 3 13:22:02 localhost kernel: [<ffffffff8107ca52>] warn_slowpath_common+0x82/0xc0 Dec 3 13:22:02 localhost kernel: [<ffffffff814542b0>] ? proc_scsi_show+0x20/0x20 Dec 3 13:22:02 localhost kernel: [<ffffffff8107cb4a>] warn_slowpath_null+0x1a/0x20 Dec 3 13:22:02 localhost kernel: [<ffffffff8167225d>] klist_iter_init_node+0x3d/0x50 Dec 3 13:22:02 localhost kernel: [<ffffffff81421d41>] bus_find_device+0x51/0xb0 Dec 3 13:22:02 localhost kernel: [<ffffffff814545ad>] scsi_seq_next+0x2d/0x40 [...] And an eventual crash. It can actually occur in any hotplug system which has a device finder and a starting device. We can fix this globally by making sure the starting node for klist_iter_init_node() is actually a member of the list before using it (and by starting from the beginning if it isn't). Reported-by: Ewan D. Milne <[email protected]> Tested-by: Ewan D. Milne <[email protected]> Signed-off-by: James Bottomley <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit 361cad3 upstream. We've seen this in a packet capture - I've intermixed what I think was going on. The fix here is to grab the so_lock sooner. 1964379 -> #1 open (for write) reply seqid=1 1964393 -> #2 open (for read) reply seqid=2 __nfs4_close(), state->n_wronly-- nfs4_state_set_mode_locked(), changes state->state = [R] state->flags is [RW] state->state is [R], state->n_wronly == 0, state->n_rdonly == 1 1964398 -> #3 open (for write) call -> because close is already running 1964399 -> downgrade (to read) call seqid=2 (close of #1) 1964402 -> #3 open (for write) reply seqid=3 __update_open_stateid() nfs_set_open_stateid_locked(), changes state->flags state->flags is [RW] state->state is [R], state->n_wronly == 0, state->n_rdonly == 1 new sequence number is exposed now via nfs4_stateid_copy() next step would be update_open_stateflags(), pending so_lock 1964403 -> downgrade reply seqid=2, fails with OLD_STATEID (close of #1) nfs4_close_prepare() gets so_lock and recalcs flags -> send close 1964405 -> downgrade (to read) call seqid=3 (close of #1 retry) __update_open_stateid() gets so_lock * update_open_stateflags() updates state->n_wronly. nfs4_state_set_mode_locked() updates state->state state->flags is [RW] state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1 * should have suppressed the preceding nfs4_close_prepare() from sending open_downgrade 1964406 -> write call 1964408 -> downgrade (to read) reply seqid=4 (close of #1 retry) nfs_clear_open_stateid_locked() state->flags is [R] state->state is [RW], state->n_wronly == 1, state->n_rdonly == 1 1964409 -> write reply (fails, openmode) Signed-off-by: Andrew Elble <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit 57adec8 upstream. Calling apply_to_page_range with an empty range results in a BUG_ON from the core code. This can be triggered by trying to load the st_drv module with CONFIG_DEBUG_SET_MODULE_RONX enabled: kernel BUG at mm/memory.c:1874! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 3 PID: 1764 Comm: insmod Not tainted 4.5.0-rc1+ #2 Hardware name: ARM Juno development board (r0) (DT) task: ffffffc9763b8000 ti: ffffffc975af8000 task.ti: ffffffc975af8000 PC is at apply_to_page_range+0x2cc/0x2d0 LR is at change_memory_common+0x80/0x108 This patch fixes the issue by making change_memory_common (called by the set_memory_* functions) a NOP when numpages == 0, therefore avoiding the erroneous call to apply_to_page_range and bringing us into line with x86 and s390. Reviewed-by: Laura Abbott <[email protected]> Acked-by: David Rientjes <[email protected]> Signed-off-by: Mika Penttilä <[email protected]> Signed-off-by: Will Deacon <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit b3aff6c upstream. Commit 4b4b451 ("arm/arm64: KVM: Rework the arch timer to use level-triggered semantics") brought the virtual architected timer closer to the VGIC. There is one occasion were we don't properly check for the VGIC actually having been initialized before, but instead go on to check the active state of some IRQ number. If userland hasn't instantiated a virtual GIC, we end up with a kernel NULL pointer dereference: ========= Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ffffffc9745c5000 [00000000] *pgd=00000009f631e003, *pud=00000009f631e003, *pmd=0000000000000000 Internal error: Oops: 96000006 [#2] PREEMPT SMP Modules linked in: CPU: 0 PID: 2144 Comm: kvm_simplest-ar Tainted: G D 4.5.0-rc2+ #1300 Hardware name: ARM Juno development board (r1) (DT) task: ffffffc976da8000 ti: ffffffc976e28000 task.ti: ffffffc976e28000 PC is at vgic_bitmap_get_irq_val+0x78/0x90 LR is at kvm_vgic_map_is_active+0xac/0xc8 pc : [<ffffffc0000b7e28>] lr : [<ffffffc0000b972c>] pstate: 20000145 .... ========= Fix this by bailing out early of kvm_timer_flush_hwstate() if we don't have a VGIC at all. Reported-by: Cosmin Gorgovan <[email protected]> Acked-by: Marc Zyngier <[email protected]> Signed-off-by: Andre Przywara <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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[ Upstream commit 7716682 ] Ilya reported following lockdep splat: kernel: ========================= kernel: [ BUG: held lock freed! ] kernel: 4.5.0-rc1-ceph-00026-g5e0a311 #1 Not tainted kernel: ------------------------- kernel: swapper/5/0 is freeing memory ffff880035c9d200-ffff880035c9dbff, with a lock still held there! kernel: (&(&queue->rskq_lock)->rlock){+.-...}, at: [<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0 kernel: 4 locks held by swapper/5/0: kernel: #0: (rcu_read_lock){......}, at: [<ffffffff8169ef6b>] netif_receive_skb_internal+0x4b/0x1f0 kernel: #1: (rcu_read_lock){......}, at: [<ffffffff816e977f>] ip_local_deliver_finish+0x3f/0x380 kernel: #2: (slock-AF_INET){+.-...}, at: [<ffffffff81685ffb>] sk_clone_lock+0x19b/0x440 kernel: #3: (&(&queue->rskq_lock)->rlock){+.-...}, at: [<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0 To properly fix this issue, inet_csk_reqsk_queue_add() needs to return to its callers if the child as been queued into accept queue. We also need to make sure listener is still there before calling sk->sk_data_ready(), by holding a reference on it, since the reference carried by the child can disappear as soon as the child is put on accept queue. Reported-by: Ilya Dryomov <[email protected]> Fixes: ebb516a ("tcp/dccp: fix race at listener dismantle phase") Signed-off-by: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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… and subvolume roots commit f32e48e upstream. The following call trace is seen when btrfs/031 test is executed in a loop, [ 158.661848] ------------[ cut here ]------------ [ 158.662634] WARNING: CPU: 2 PID: 890 at /home/chandan/repos/linux/fs/btrfs/ioctl.c:558 create_subvol+0x3d1/0x6ea() [ 158.664102] BTRFS: Transaction aborted (error -2) [ 158.664774] Modules linked in: [ 158.665266] CPU: 2 PID: 890 Comm: btrfs Not tainted 4.4.0-rc6-g511711a #2 [ 158.666251] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [ 158.667392] ffffffff81c0a6b0 ffff8806c7c4f8e8 ffffffff81431fc8 ffff8806c7c4f930 [ 158.668515] ffff8806c7c4f920 ffffffff81051aa1 ffff880c85aff000 ffff8800bb44d000 [ 158.669647] ffff8808863b5c98 0000000000000000 00000000fffffffe ffff8806c7c4f980 [ 158.670769] Call Trace: [ 158.671153] [<ffffffff81431fc8>] dump_stack+0x44/0x5c [ 158.671884] [<ffffffff81051aa1>] warn_slowpath_common+0x81/0xc0 [ 158.672769] [<ffffffff81051b27>] warn_slowpath_fmt+0x47/0x50 [ 158.673620] [<ffffffff813bc98d>] create_subvol+0x3d1/0x6ea [ 158.674440] [<ffffffff813777c9>] btrfs_mksubvol.isra.30+0x369/0x520 [ 158.675376] [<ffffffff8108a4aa>] ? percpu_down_read+0x1a/0x50 [ 158.676235] [<ffffffff81377a81>] btrfs_ioctl_snap_create_transid+0x101/0x180 [ 158.677268] [<ffffffff81377b52>] btrfs_ioctl_snap_create+0x52/0x70 [ 158.678183] [<ffffffff8137afb4>] btrfs_ioctl+0x474/0x2f90 [ 158.678975] [<ffffffff81144b8e>] ? vma_merge+0xee/0x300 [ 158.679751] [<ffffffff8115be31>] ? alloc_pages_vma+0x91/0x170 [ 158.680599] [<ffffffff81123f62>] ? lru_cache_add_active_or_unevictable+0x22/0x70 [ 158.681686] [<ffffffff813d99cf>] ? selinux_file_ioctl+0xff/0x1d0 [ 158.682581] [<ffffffff8117b791>] do_vfs_ioctl+0x2c1/0x490 [ 158.683399] [<ffffffff813d3cde>] ? security_file_ioctl+0x3e/0x60 [ 158.684297] [<ffffffff8117b9d4>] SyS_ioctl+0x74/0x80 [ 158.685051] [<ffffffff819b2bd7>] entry_SYSCALL_64_fastpath+0x12/0x6a [ 158.685958] ---[ end trace 4b63312de5a2cb76 ]--- [ 158.686647] BTRFS: error (device loop0) in create_subvol:558: errno=-2 No such entry [ 158.709508] BTRFS info (device loop0): forced readonly [ 158.737113] BTRFS info (device loop0): disk space caching is enabled [ 158.738096] BTRFS error (device loop0): Remounting read-write after error is not allowed [ 158.851303] BTRFS error (device loop0): cleaner transaction attach returned -30 This occurs because, Mount filesystem Create subvol with ID 257 Unmount filesystem Mount filesystem Delete subvol with ID 257 btrfs_drop_snapshot() Add root corresponding to subvol 257 into btrfs_transaction->dropped_roots list Create new subvol (i.e. create_subvol()) 257 is returned as the next free objectid btrfs_read_fs_root_no_name() Finds the btrfs_root instance corresponding to the old subvol with ID 257 in btrfs_fs_info->fs_roots_radix. Returns error since btrfs_root_item->refs has the value of 0. To fix the issue the commit initializes tree root's and subvolume root's highest_objectid when loading the roots from disk. Signed-off-by: Chandan Rajendra <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit 4c58f32 upstream. The fixes provided in this patch assigns a valid net_device structure to skb before dispatching it for further processing. Scenario #1: ============ Bluetooth 6lowpan receives an uncompressed IPv6 header, and dispatches it to netif. The following error occurs: Null pointer dereference error #1 crash log: [ 845.854013] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 [ 845.855785] IP: [<ffffffff816e3d36>] enqueue_to_backlog+0x56/0x240 ... [ 845.909459] Call Trace: [ 845.911678] [<ffffffff816e3f64>] netif_rx_internal+0x44/0xf0 The first modification fixes the NULL pointer dereference error by assigning dev to the local_skb in order to set a valid net_device before processing the skb by netif_rx_ni(). Scenario #2: ============ Bluetooth 6lowpan receives an UDP compressed message which needs further decompression by nhc_udp. The following error occurs: Null pointer dereference error #2 crash log: [ 63.295149] BUG: unable to handle kernel NULL pointer dereference at 0000000000000840 [ 63.295931] IP: [<ffffffffc0559540>] udp_uncompress+0x320/0x626 [nhc_udp] The second modification fixes the NULL pointer dereference error by assigning dev to the local_skb in the case of a udp compressed packet. The 6lowpan udp_uncompress function expects that the net_device is set in the skb when checking lltype. Signed-off-by: Glenn Ruben Bakke <[email protected]> Signed-off-by: Lukasz Duda <[email protected]> Acked-by: Jukka Rissanen <[email protected]> Signed-off-by: Johan Hedberg <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit 5610b12 upstream. This patch is borrowed from x86 hpet driver and explaind below: Due to the overly intelligent design of HPETs, we need to workaround the problem that the compare value which we write is already behind the actual counter value at the point where the value hits the real compare register. This happens for two reasons: 1) We read out the counter, add the delta and write the result to the compare register. When a NMI hits between the read out and the write then the counter can be ahead of the event already. 2) The write to the compare register is delayed by up to two HPET cycles in AMD chipsets. We can work around this by reading back the compare register to make sure that the written value has hit the hardware. But that is bad performance wise for the normal case where the event is far enough in the future. As we already know that the write can be delayed by up to two cycles we can avoid the read back of the compare register completely if we make the decision whether the delta has elapsed already or not based on the following calculation: cmp = event - actual_count; If cmp is less than 64 HPET clock cycles, then we decide that the event has happened already and return -ETIME. That covers the above #1 and #2 problems which would cause a wait for HPET wraparound (~306 seconds). Signed-off-by: Huacai Chen <[email protected]> Cc: Aurelien Jarno <[email protected]> Cc: Steven J. Hill <[email protected]> Cc: Fuxin Zhang <[email protected]> Cc: Zhangjin Wu <[email protected]> Cc: Huacai Chen <[email protected]> Cc: [email protected] Patchwork: https://patchwork.linux-mips.org/patch/12162/ Signed-off-by: Ralf Baechle <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit cbfe74a upstream. Returning to delay slot, riding an interrupti, had one loose end. AUX_USER_SP used for restoring user mode SP upon RTIE was not being setup from orig task's saved value, causing task to use wrong SP, leading to ProtV errors. The reason being: - INTERRUPT_EPILOGUE returns to a kernel trampoline, thus not expected to restore it - EXCEPTION_EPILOGUE is not used at all Fix that by restoring AUX_USER_SP explicitly in the trampoline. This was broken in the original workaround, but the error scenarios got reduced considerably since v3.14 due to following: 1. The Linuxthreads.old based userspace at the time caused many more exceptions in delay slot than the current NPTL based one. Infact with current userspace the error doesn't happen at all. 2. Return from interrupt (delay slot or otherwise) doesn't get exercised much after commit 4de0e52 ("Really Re-enable interrupts to avoid deadlocks") since IRQ_ACTIVE.active being clear means most returns are as if from pure kernel (even for active interrupts) Infact the issue only happened in an experimental branch where I was tinkering with reverted 4de0e52 Fixes: 4255b07 ("ARCv2: STAR 9000793984: Handle return from intr to Delay Slot") Signed-off-by: Vineet Gupta <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit c2d6cb1 upstream. While running a stress test I ran into a deadlock when running the delayed iputs at transaction time, which produced the following report and trace: [ 886.399989] ============================================= [ 886.400871] [ INFO: possible recursive locking detected ] [ 886.401663] 4.4.0-rc6-btrfs-next-18+ #1 Not tainted [ 886.402384] --------------------------------------------- [ 886.403182] fio/8277 is trying to acquire lock: [ 886.403568] (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] but task is already holding lock: [ 886.403568] (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] other info that might help us debug this: [ 886.403568] Possible unsafe locking scenario: [ 886.403568] [ 886.403568] CPU0 [ 886.403568] ---- [ 886.403568] lock(&fs_info->delayed_iput_sem); [ 886.403568] lock(&fs_info->delayed_iput_sem); [ 886.403568] [ 886.403568] *** DEADLOCK *** [ 886.403568] [ 886.403568] May be due to missing lock nesting notation [ 886.403568] [ 886.403568] 3 locks held by fio/8277: [ 886.403568] #0: (sb_writers#11){.+.+.+}, at: [<ffffffff81174c4c>] __sb_start_write+0x5f/0xb0 [ 886.403568] #1: (&sb->s_type->i_mutex_key#15){+.+.+.}, at: [<ffffffffa054620d>] btrfs_file_write_iter+0x73/0x408 [btrfs] [ 886.403568] #2: (&fs_info->delayed_iput_sem){++++..}, at: [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.403568] [ 886.403568] stack backtrace: [ 886.403568] CPU: 6 PID: 8277 Comm: fio Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 886.403568] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [ 886.403568] 0000000000000000 ffff88009f80f770 ffffffff8125d4fd ffffffff82af1fc0 [ 886.403568] ffff88009f80f830 ffffffff8108e5f9 0000000200000000 ffff88009fd92290 [ 886.403568] 0000000000000000 ffffffff82af1fc0 ffffffff829cfb01 00042b216d008804 [ 886.403568] Call Trace: [ 886.403568] [<ffffffff8125d4fd>] dump_stack+0x4e/0x79 [ 886.403568] [<ffffffff8108e5f9>] __lock_acquire+0xd42/0xf0b [ 886.403568] [<ffffffff810c22db>] ? __module_address+0xdf/0x108 [ 886.403568] [<ffffffff8108eb77>] lock_acquire+0x10d/0x194 [ 886.403568] [<ffffffff8108eb77>] ? lock_acquire+0x10d/0x194 [ 886.403568] [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffff8148556b>] down_read+0x3e/0x4d [ 886.489542] [<ffffffffa0538823>] ? btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffffa0538823>] btrfs_run_delayed_iputs+0x36/0xbf [btrfs] [ 886.489542] [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs] [ 886.489542] [<ffffffffa0521d7a>] flush_space+0x435/0x44a [btrfs] [ 886.489542] [<ffffffffa052218b>] ? reserve_metadata_bytes+0x26a/0x384 [btrfs] [ 886.489542] [<ffffffffa05221ae>] reserve_metadata_bytes+0x28d/0x384 [btrfs] [ 886.489542] [<ffffffffa052256c>] ? btrfs_block_rsv_refill+0x58/0x96 [btrfs] [ 886.489542] [<ffffffffa0522584>] btrfs_block_rsv_refill+0x70/0x96 [btrfs] [ 886.489542] [<ffffffffa053d747>] btrfs_evict_inode+0x394/0x55a [btrfs] [ 886.489542] [<ffffffff81188e31>] evict+0xa7/0x15c [ 886.489542] [<ffffffff81189878>] iput+0x1d3/0x266 [ 886.489542] [<ffffffffa053887c>] btrfs_run_delayed_iputs+0x8f/0xbf [btrfs] [ 886.489542] [<ffffffffa0533953>] btrfs_commit_transaction+0x8f5/0x96e [btrfs] [ 886.489542] [<ffffffff81085096>] ? signal_pending_state+0x31/0x31 [ 886.489542] [<ffffffffa0521191>] btrfs_alloc_data_chunk_ondemand+0x1d7/0x288 [btrfs] [ 886.489542] [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs] [ 886.489542] [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs] [ 886.489542] [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs] [ 886.489542] [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128 [ 886.489542] [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs] [ 886.489542] [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50 [ 886.489542] [<ffffffff8117279e>] __vfs_write+0x7c/0xa5 [ 886.489542] [<ffffffff81172cda>] vfs_write+0xa0/0xe4 [ 886.489542] [<ffffffff811734cc>] SyS_write+0x50/0x7e [ 886.489542] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f [ 1081.852335] INFO: task fio:8244 blocked for more than 120 seconds. [ 1081.854348] Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 1081.857560] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1081.863227] fio D ffff880213f9bb28 0 8244 8240 0x00000000 [ 1081.868719] ffff880213f9bb28 00ffffff810fc6b0 ffffffff0000000a ffff88023ed55240 [ 1081.872499] ffff880206b5d400 ffff880213f9c000 ffff88020a4d5318 ffff880206b5d400 [ 1081.876834] ffffffff00000001 ffff880206b5d400 ffff880213f9bb40 ffffffff81482ba4 [ 1081.880782] Call Trace: [ 1081.881793] [<ffffffff81482ba4>] schedule+0x7f/0x97 [ 1081.883340] [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325 [ 1081.895525] [<ffffffff8108d48d>] ? trace_hardirqs_on_caller+0x16/0x1ab [ 1081.897419] [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20 [ 1081.899251] [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20 [ 1081.901063] [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21 [ 1081.902365] [<ffffffff814855bd>] down_write+0x43/0x57 [ 1081.903846] [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1081.906078] [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1081.908846] [<ffffffff8108d461>] ? mark_held_locks+0x56/0x6c [ 1081.910409] [<ffffffffa0521282>] btrfs_check_data_free_space+0x40/0x59 [btrfs] [ 1081.912482] [<ffffffffa05228f5>] btrfs_delalloc_reserve_space+0x1e/0x4e [btrfs] [ 1081.914597] [<ffffffffa053620a>] btrfs_direct_IO+0x10c/0x27e [btrfs] [ 1081.919037] [<ffffffff8111d9a1>] generic_file_direct_write+0xb3/0x128 [ 1081.920754] [<ffffffffa05463c3>] btrfs_file_write_iter+0x229/0x408 [btrfs] [ 1081.922496] [<ffffffff8108ae38>] ? __lock_is_held+0x38/0x50 [ 1081.923922] [<ffffffff8117279e>] __vfs_write+0x7c/0xa5 [ 1081.925275] [<ffffffff81172cda>] vfs_write+0xa0/0xe4 [ 1081.926584] [<ffffffff811734cc>] SyS_write+0x50/0x7e [ 1081.927968] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f [ 1081.985293] INFO: lockdep is turned off. [ 1081.986132] INFO: task fio:8249 blocked for more than 120 seconds. [ 1081.987434] Not tainted 4.4.0-rc6-btrfs-next-18+ #1 [ 1081.988534] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1081.990147] fio D ffff880218febbb8 0 8249 8240 0x00000000 [ 1081.991626] ffff880218febbb8 00ffffff81486b8e ffff88020000000b ffff88023ed75240 [ 1081.993258] ffff8802120a9a00 ffff880218fec000 ffff88020a4d5318 ffff8802120a9a00 [ 1081.994850] ffffffff00000001 ffff8802120a9a00 ffff880218febbd0 ffffffff81482ba4 [ 1081.996485] Call Trace: [ 1081.997037] [<ffffffff81482ba4>] schedule+0x7f/0x97 [ 1081.998017] [<ffffffff81485eb5>] rwsem_down_write_failed+0x2d5/0x325 [ 1081.999241] [<ffffffff810852a5>] ? finish_wait+0x6d/0x76 [ 1082.000306] [<ffffffff81269723>] call_rwsem_down_write_failed+0x13/0x20 [ 1082.001533] [<ffffffff81269723>] ? call_rwsem_down_write_failed+0x13/0x20 [ 1082.002776] [<ffffffff81089fae>] ? __down_write_nested.isra.0+0x1f/0x21 [ 1082.003995] [<ffffffff814855bd>] down_write+0x43/0x57 [ 1082.005000] [<ffffffffa05211b0>] ? btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1082.007403] [<ffffffffa05211b0>] btrfs_alloc_data_chunk_ondemand+0x1f6/0x288 [btrfs] [ 1082.008988] [<ffffffffa0545064>] btrfs_fallocate+0x7c1/0xc2f [btrfs] [ 1082.010193] [<ffffffff8108a1ba>] ? percpu_down_read+0x4e/0x77 [ 1082.011280] [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0 [ 1082.012265] [<ffffffff81174c4c>] ? __sb_start_write+0x5f/0xb0 [ 1082.013021] [<ffffffff811712e4>] vfs_fallocate+0x170/0x1ff [ 1082.013738] [<ffffffff81181ebb>] ioctl_preallocate+0x89/0x9b [ 1082.014778] [<ffffffff811822d7>] do_vfs_ioctl+0x40a/0x4ea [ 1082.015778] [<ffffffff81176ea7>] ? SYSC_newfstat+0x25/0x2e [ 1082.016806] [<ffffffff8118b4de>] ? __fget_light+0x4d/0x71 [ 1082.017789] [<ffffffff8118240e>] SyS_ioctl+0x57/0x79 [ 1082.018706] [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f This happens because we can recursively acquire the semaphore fs_info->delayed_iput_sem when attempting to allocate space to satisfy a file write request as shown in the first trace above - when committing a transaction we acquire (down_read) the semaphore before running the delayed iputs, and when running a delayed iput() we can end up calling an inode's eviction handler, which in turn commits another transaction and attempts to acquire (down_read) again the semaphore to run more delayed iput operations. This results in a deadlock because if a task acquires multiple times a semaphore it should invoke down_read_nested() with a different lockdep class for each level of recursion. Fix this by simplifying the implementation and use a mutex instead that is acquired by the cleaner kthread before it runs the delayed iputs instead of always acquiring a semaphore before delayed references are run from anywhere. Fixes: d7c1517 (btrfs: Fix NO_SPACE bug caused by delayed-iput) Signed-off-by: Filipe Manana <[email protected]> Signed-off-by: Chris Mason <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit 79e3f4a upstream. Commit cbce790 ("PCI: designware: Make driver arch-agnostic") changed the host bridge sysdata pointer from the ARM pci_sys_data to the DesignWare pcie_port structure, and changed pcie-designware.c to reflect that. But it did not change the corresponding code in pci-keystone-dw.c, so it caused crashes on Keystone: Unable to handle kernel NULL pointer dereference at virtual address 00000030 pgd = c0003000 [00000030] *pgd=80000800004003, *pmd=00000000 Internal error: Oops: 206 [#1] PREEMPT SMP ARM CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.2-00139-gb74f926 #2 Hardware name: Keystone PC is at ks_dw_pcie_msi_irq_unmask+0x24/0x58 Change pci-keystone-dw.c to expect sysdata to be the struct pcie_port pointer. [bhelgaas: changelog] Fixes: cbce790 ("PCI: designware: Make driver arch-agnostic") Signed-off-by: Murali Karicheri <[email protected]> Signed-off-by: Bjorn Helgaas <[email protected]> CC: Zhou Wang <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit d144dfe upstream. If we use USB ID pin as wakeup source, and there is a USB block device on this USB OTG (ID) cable, the system will be deadlock after system resume. The root cause for this problem is: the workqueue ci_otg may try to remove hcd before the driver resume has finished, and hcd will disconnect the device on it, then, it will call device_release_driver, and holds the device lock "dev->mutex", but it is never unlocked since it waits workqueue writeback to run to flush the block information, but the workqueue writeback is freezable, it is not thawed before driver resume has finished. When the driver (device: sd 0:0:0:0:) resume goes to dpm_complete, it tries to get its device lock "dev->mutex", but it can't get it forever, then the deadlock occurs. Below call stacks show the situation. So, in order to fix this problem, we need to change workqueue ci_otg as freezable, then the work item in this workqueue will be run after driver's resume, this workqueue will not be blocked forever like above case since the workqueue writeback has been thawed too. Tested at: i.mx6qdl-sabresd and i.mx6sx-sdb. [ 555.178869] kworker/u2:13 D c07de74c 0 826 2 0x00000000 [ 555.185310] Workqueue: ci_otg ci_otg_work [ 555.189353] Backtrace: [ 555.191849] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0) [ 555.198912] r10:ee471ba0 r9:00000000 r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4 [ 555.206867] r4:ee470000 [ 555.209453] [<c07dec24>] (schedule) from [<c07e2fc4>] (schedule_timeout+0x15c/0x1e0) [ 555.217212] r4:7fffffff r3:edc2b000 [ 555.220862] [<c07e2e68>] (schedule_timeout) from [<c07df6c8>] (wait_for_common+0x94/0x144) [ 555.229140] r8:00000000 r7:00000002 r6:ee470000 r5:ee471ba4 r4:7fffffff [ 555.235980] [<c07df634>] (wait_for_common) from [<c07df790>] (wait_for_completion+0x18/0x1c) [ 555.244430] r10:00000001 r9:c0b5563c r8:c0042e48 r7:ef086000 r6:eea4372c r5:ef131b00 [ 555.252383] r4:00000000 [ 555.254970] [<c07df778>] (wait_for_completion) from [<c0043cb8>] (flush_work+0x19c/0x234) [ 555.263177] [<c0043b1c>] (flush_work) from [<c0043fac>] (flush_delayed_work+0x48/0x4c) [ 555.271106] r8:ed5b5000 r7:c0b38a3c r6:eea439cc r5:eea4372c r4:eea4372c [ 555.277958] [<c0043f64>] (flush_delayed_work) from [<c00eae18>] (bdi_unregister+0x84/0xec) [ 555.286236] r4:eea43520 r3:20000153 [ 555.289885] [<c00ead94>] (bdi_unregister) from [<c02c2154>] (blk_cleanup_queue+0x180/0x29c) [ 555.298250] r5:eea43808 r4:eea43400 [ 555.301909] [<c02c1fd4>] (blk_cleanup_queue) from [<c0417914>] (__scsi_remove_device+0x48/0xb8) [ 555.310623] r7:00000000 r6:20000153 r5:ededa950 r4:ededa800 [ 555.316403] [<c04178cc>] (__scsi_remove_device) from [<c0415e90>] (scsi_forget_host+0x64/0x68) [ 555.325028] r5:ededa800 r4:ed5b5000 [ 555.328689] [<c0415e2c>] (scsi_forget_host) from [<c0409828>] (scsi_remove_host+0x78/0x104) [ 555.337054] r5:ed5b5068 r4:ed5b5000 [ 555.340709] [<c04097b0>] (scsi_remove_host) from [<c04cdfcc>] (usb_stor_disconnect+0x50/0xb4) [ 555.349247] r6:ed5b56e4 r5:ed5b5818 r4:ed5b5690 r3:00000008 [ 555.355025] [<c04cdf7c>] (usb_stor_disconnect) from [<c04b3bc8>] (usb_unbind_interface+0x78/0x25c) [ 555.363997] r8:c13919b4 r7:edd3c000 r6:edd3c020 r5:ee551c68 r4:ee551c00 r3:c04cdf7c [ 555.371892] [<c04b3b50>] (usb_unbind_interface) from [<c03dc248>] (__device_release_driver+0x8c/0x118) [ 555.381213] r10:00000001 r9:edd90c00 r8:c13919b4 r7:ee551c68 r6:c0b546e0 r5:c0b5563c [ 555.389167] r4:edd3c020 [ 555.391752] [<c03dc1bc>] (__device_release_driver) from [<c03dc2fc>] (device_release_driver+0x28/0x34) [ 555.401071] r5:edd3c020 r4:edd3c054 [ 555.404721] [<c03dc2d4>] (device_release_driver) from [<c03db304>] (bus_remove_device+0xe0/0x110) [ 555.413607] r5:edd3c020 r4:ef17f04c [ 555.417253] [<c03db224>] (bus_remove_device) from [<c03d8128>] (device_del+0x114/0x21c) [ 555.425270] r6:edd3c028 r5:edd3c020 r4:ee551c00 r3:00000000 [ 555.431045] [<c03d8014>] (device_del) from [<c04b1560>] (usb_disable_device+0xa4/0x1e8) [ 555.439061] r8:edd3c000 r7:eded8000 r6:00000000 r5:00000001 r4:ee551c00 [ 555.445906] [<c04b14bc>] (usb_disable_device) from [<c04a8e54>] (usb_disconnect+0x74/0x224) [ 555.454271] r9:edd90c00 r8:ee551000 r7:ee551c68 r6:ee551c9c r5:ee551c00 r4:00000001 [ 555.462156] [<c04a8de0>] (usb_disconnect) from [<c04a8fb8>] (usb_disconnect+0x1d8/0x224) [ 555.470259] r10:00000001 r9:edd90000 r8:ee471e2c r7:ee551468 r6:ee55149c r5:ee551400 [ 555.478213] r4:00000001 [ 555.480797] [<c04a8de0>] (usb_disconnect) from [<c04ae5ec>] (usb_remove_hcd+0xa0/0x1ac) [ 555.488813] r10:00000001 r9:ee471eb0 r8:00000000 r7:ef3d9500 r6:eded810c r5:eded80b0 [ 555.496765] r4:eded8000 [ 555.499351] [<c04ae54c>] (usb_remove_hcd) from [<c04d4158>] (host_stop+0x28/0x64) [ 555.506847] r6:eeb50010 r5:eded8000 r4:eeb51010 [ 555.511563] [<c04d4130>] (host_stop) from [<c04d09b8>] (ci_otg_work+0xc4/0x124) [ 555.518885] r6:00000001 r5:eeb50010 r4:eeb502a0 r3:c04d4130 [ 555.524665] [<c04d08f4>] (ci_otg_work) from [<c00454f0>] (process_one_work+0x194/0x420) [ 555.532682] r6:ef086000 r5:eeb502a0 r4:edc44480 [ 555.537393] [<c004535c>] (process_one_work) from [<c00457b0>] (worker_thread+0x34/0x514) [ 555.545496] r10:edc44480 r9:ef086000 r8:c0b1a100 r7:ef086034 r6:00000088 r5:edc44498 [ 555.553450] r4:ef086000 [ 555.556032] [<c004577c>] (worker_thread) from [<c004bab4>] (kthread+0xdc/0xf8) [ 555.563268] r10:00000000 r9:00000000 r8:00000000 r7:c004577c r6:edc44480 r5:eddc15c0 [ 555.571221] r4:00000000 [ 555.573804] [<c004b9d8>] (kthread) from [<c000fef0>] (ret_from_fork+0x14/0x24) [ 555.581040] r7:00000000 r6:00000000 r5:c004b9d8 r4:eddc15c0 [ 553.429383] sh D c07de74c 0 694 691 0x00000000 [ 553.435801] Backtrace: [ 553.438295] [<c07de4fc>] (__schedule) from [<c07dec6c>] (schedule+0x48/0xa0) [ 553.445358] r10:edd3c054 r9:edd3c078 r8:edddbd50 r7:edcbbc00 r6:c1377c34 r5:60000153 [ 553.453313] r4:eddda000 [ 553.455896] [<c07dec24>] (schedule) from [<c07deff8>] (schedule_preempt_disabled+0x10/0x14) [ 553.464261] r4:edd3c058 r3:0000000a [ 553.467910] [<c07defe8>] (schedule_preempt_disabled) from [<c07e0bbc>] (mutex_lock_nested+0x1a0/0x3e8) [ 553.477254] [<c07e0a1c>] (mutex_lock_nested) from [<c03e927c>] (dpm_complete+0xc0/0x1b0) [ 553.485358] r10:00561408 r9:edd3c054 r8:c0b4863c r7:edddbd90 r6:c0b485d8 r5:edd3c020 [ 553.493313] r4:edd3c0d0 [ 553.495896] [<c03e91bc>] (dpm_complete) from [<c03e9388>] (dpm_resume_end+0x1c/0x20) [ 553.503652] r9:00000000 r8:c0b1a9d0 r7:c1334ec0 r6:c1334edc r5:00000003 r4:00000010 [ 553.511544] [<c03e936c>] (dpm_resume_end) from [<c0079894>] (suspend_devices_and_enter+0x158/0x504) [ 553.520604] r4:00000000 r3:c1334efc [ 553.524250] [<c007973c>] (suspend_devices_and_enter) from [<c0079e74>] (pm_suspend+0x234/0x2cc) [ 553.532961] r10:00561408 r9:ed6b7300 r8:00000004 r7:c1334eec r6:00000000 r5:c1334ee8 [ 553.540914] r4:00000003 [ 553.543493] [<c0079c40>] (pm_suspend) from [<c0078a6c>] (state_store+0x6c/0xc0) [ 555.703684] 7 locks held by kworker/u2:13/826: [ 555.708140] #0: ("%s""ci_otg"){++++.+}, at: [<c0045484>] process_one_work+0x128/0x420 [ 555.716277] #1: ((&ci->work)){+.+.+.}, at: [<c0045484>] process_one_work+0x128/0x420 [ 555.724317] #2: (usb_bus_list_lock){+.+.+.}, at: [<c04ae5e4>] usb_remove_hcd+0x98/0x1ac [ 555.732626] #3: (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224 [ 555.740403] #4: (&dev->mutex){......}, at: [<c04a8e28>] usb_disconnect+0x48/0x224 [ 555.748179] #5: (&dev->mutex){......}, at: [<c03dc2f4>] device_release_driver+0x20/0x34 [ 555.756487] #6: (&shost->scan_mutex){+.+.+.}, at: [<c04097d0>] scsi_remove_host+0x20/0x104 Cc: Jun Li <[email protected]> Signed-off-by: Peter Chen <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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May 4, 2016
commit 6acfe68 upstream. Request-based DM's blk-mq support (dm-mq) was reported to be 50% slower than if an underlying null_blk device were used directly. One of the reasons for this drop in performance is that blk_insert_clone_request() was calling blk_mq_insert_request() with @async=true. This forced the use of kblockd_schedule_delayed_work_on() to run the blk-mq hw queues which ushered in ping-ponging between process context (fio in this case) and kblockd's kworker to submit the cloned request. The ftrace function_graph tracer showed: kworker-2013 => fio-12190 fio-12190 => kworker-2013 ... kworker-2013 => fio-12190 fio-12190 => kworker-2013 ... Fixing blk_insert_clone_request()'s blk_mq_insert_request() call to _not_ use kblockd to submit the cloned requests isn't enough to eliminate the observed context switches. In addition to this dm-mq specific blk-core fix, there are 2 DM core fixes to dm-mq that (when paired with the blk-core fix) completely eliminate the observed context switching: 1) don't blk_mq_run_hw_queues in blk-mq request completion Motivated by desire to reduce overhead of dm-mq, punting to kblockd just increases context switches. In my testing against a really fast null_blk device there was no benefit to running blk_mq_run_hw_queues() on completion (and no other blk-mq driver does this). So hopefully this change doesn't induce the need for yet another revert like commit 621739b ! 2) use blk_mq_complete_request() in dm_complete_request() blk_complete_request() doesn't offer the traditional q->mq_ops vs .request_fn branching pattern that other historic block interfaces do (e.g. blk_get_request). Using blk_mq_complete_request() for blk-mq requests is important for performance. It should be noted that, like blk_complete_request(), blk_mq_complete_request() doesn't natively handle partial completions -- but the request-based DM-multipath target does provide the required partial completion support by dm.c:end_clone_bio() triggering requeueing of the request via dm-mpath.c:multipath_end_io()'s return of DM_ENDIO_REQUEUE. dm-mq fix #2 is _much_ more important than #1 for eliminating the context switches. Before: cpu : usr=15.10%, sys=59.39%, ctx=7905181, majf=0, minf=475 After: cpu : usr=20.60%, sys=79.35%, ctx=2008, majf=0, minf=472 With these changes multithreaded async read IOPs improved from ~950K to ~1350K for this dm-mq stacked on null_blk test-case. The raw read IOPs of the underlying null_blk device for the same workload is ~1950K. Fixes: 7fb4898 ("block: add blk-mq support to blk_insert_cloned_request()") Fixes: bfebd1c ("dm: add full blk-mq support to request-based DM") Reported-by: Sagi Grimberg <[email protected]> Signed-off-by: Mike Snitzer <[email protected]> Acked-by: Jens Axboe <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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[ Upstream commit 9b36881 ] We need to update the skb->csum after pulling the skb, otherwise an unnecessary checksum (re)computation can ocure for IGMP/MLD packets in the bridge code. Additionally this fixes the following splats for network devices / bridge ports with support for and enabled RX checksum offloading: [...] [ 43.986968] eth0: hw csum failure [ 43.990344] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.4.0 #2 [ 43.996193] Hardware name: BCM2709 [ 43.999647] [<800204e0>] (unwind_backtrace) from [<8001cf14>] (show_stack+0x10/0x14) [ 44.007432] [<8001cf14>] (show_stack) from [<801ab614>] (dump_stack+0x80/0x90) [ 44.014695] [<801ab614>] (dump_stack) from [<802e4548>] (__skb_checksum_complete+0x6c/0xac) [ 44.023090] [<802e4548>] (__skb_checksum_complete) from [<803a055c>] (ipv6_mc_validate_checksum+0x104/0x178) [ 44.032959] [<803a055c>] (ipv6_mc_validate_checksum) from [<802e111c>] (skb_checksum_trimmed+0x130/0x188) [ 44.042565] [<802e111c>] (skb_checksum_trimmed) from [<803a06e8>] (ipv6_mc_check_mld+0x118/0x338) [ 44.051501] [<803a06e8>] (ipv6_mc_check_mld) from [<803b2c98>] (br_multicast_rcv+0x5dc/0xd00) [ 44.060077] [<803b2c98>] (br_multicast_rcv) from [<803aa510>] (br_handle_frame_finish+0xac/0x51c) [...] Fixes: 9afd85c ("net: Export IGMP/MLD message validation code") Reported-by: Álvaro Fernández Rojas <[email protected]> Signed-off-by: Linus Lüssing <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit cf0a254 upstream. BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 1, irqs_disabled(): 128, pid: 383, name: sh Preemption disabled at:[<ffff800000124c18>] kgdb_cpu_enter+0x158/0x6b8 CPU: 3 PID: 383 Comm: sh Tainted: G W 4.1.13-rt13 #2 Hardware name: Freescale Layerscape 2085a RDB Board (DT) Call trace: [<ffff8000000885e8>] dump_backtrace+0x0/0x128 [<ffff800000088734>] show_stack+0x24/0x30 [<ffff80000079a7c4>] dump_stack+0x80/0xa0 [<ffff8000000bd324>] ___might_sleep+0x18c/0x1a0 [<ffff8000007a20ac>] __rt_spin_lock+0x2c/0x40 [<ffff8000007a2268>] rt_read_lock+0x40/0x58 [<ffff800000085328>] single_step_handler+0x38/0xd8 [<ffff800000082368>] do_debug_exception+0x58/0xb8 Exception stack(0xffff80834a1e7c80 to 0xffff80834a1e7da0) 7c80: ffffff9c ffffffff 92c23ba0 0000ffff 4a1e7e4 ffff8083 001bfcc4 ffff8000 7ca0: f2000400 00000000 00000000 00000000 4a1e7d80 ffff8083 0049501c ffff8000 7cc0: 00005402 00000000 00aaa210 ffff8000 4a1e7ea0 ffff8083 000833f4 ffff8000 7ce0: ffffff9c ffffffff 92c23ba0 0000ffff 4a1e7ea0 ffff8083 001bfcc0 ffff8000 7d00: 4a0fc400 ffff8083 00005402 00000000 4a1e7d40 ffff8083 00490324 ffff8000 7d20: ffffff9c 00000000 92c23ba0 0000ffff 000a0000 00000000 00000000 00000000 7d40: 00000008 00000000 00080000 00000000 92c23b8 0000ffff 92c23b8e 0000ffff 7d60: 00000038 00000000 00001cb2 00000000 00000005 00000000 92d7b498 0000ffff 7d80: 01010101 01010101 92be9000 0000ffff 00000000 00000000 00000030 00000000 [<ffff8000000833f4>] el1_dbg+0x18/0x6c This issue is similar with 62c6c61("arm64: replace read_lock to rcu lock in call_break_hook"), but comes to single_step_handler. This also solves kgdbts boot test silent hang issue on 4.4 -rt kernel. Signed-off-by: Yang Shi <[email protected]> Acked-by: Will Deacon <[email protected]> Signed-off-by: Catalin Marinas <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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May 11, 2016
Tracing a workload that uses transactions gave a seg fault as follows: perf record -e intel_pt// workload perf report Program received signal SIGSEGV, Segmentation fault. 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) at util/intel-pt.c:929 929 ptq->last_branch_rb->nr = 0; (gdb) p ptq->last_branch_rb $1 = (struct branch_stack *) 0x0 (gdb) up 1148 intel_pt_reset_last_branch_rb(ptq); (gdb) l 1143 if (ret) 1144 pr_err("Intel Processor Trace: failed to deliver transaction event 1145 ret); 1146 1147 if (pt->synth_opts.callchain) 1148 intel_pt_reset_last_branch_rb(ptq); 1149 1150 return ret; 1151 } 1152 (gdb) p pt->synth_opts.callchain $2 = true (gdb) (gdb) bt #0 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) #1 0x000000000054c1e0 in intel_pt_synth_transaction_sample (ptq=0x1a36110) #2 0x000000000054c5b2 in intel_pt_sample (ptq=0x1a36110) Caused by checking the 'callchain' flag when it should have been the 'last_branch' flag. Fix that. Reported-by: Andi Kleen <[email protected]> Signed-off-by: Adrian Hunter <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: [email protected] # v4.4+ Fixes: f14445e ("perf intel-pt: Support generating branch stack") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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May 11, 2016
When I was writing an atomic wrapper for rmfb, I ran into the following backtrace from lockdep: ============================================= [ INFO: possible recursive locking detected ] 4.5.0-patser+ #4696 Tainted: G U --------------------------------------------- kworker/2:2/2608 is trying to acquire lock: (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c9ddc>] drm_modeset_lock+0x7c/0x120 [drm] but task is already holding lock: (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(crtc_ww_class_mutex); lock(crtc_ww_class_mutex); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by kworker/2:2/2608: #0: ("events"){.+.+.+}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0 #1: ((&arg.work)){+.+.+.}, at: [<ffffffff810a5eea>] process_one_work+0x15a/0x6c0 #2: (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffc004532a>] drm_atomic_helper_remove_fb+0x4a/0x1d0 [drm_kms_helper] #3: (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffc00c98cd>] modeset_backoff+0x8d/0x220 [drm] While lockdep probably catches this bug when it happens, it's better to explicitly warn when state->acquire_ctx is not set. Signed-off-by: Maarten Lankhorst <[email protected]> Signed-off-by: Daniel Vetter <[email protected]> Link: http://patchwork.freedesktop.org/patch/msgid/1462266751-29123-1-git-send-email-maarten.lankhorst@linux.intel.com
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Aug 9, 2016
commit 1342e0b upstream. Tracing a workload that uses transactions gave a seg fault as follows: perf record -e intel_pt// workload perf report Program received signal SIGSEGV, Segmentation fault. 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) at util/intel-pt.c:929 929 ptq->last_branch_rb->nr = 0; (gdb) p ptq->last_branch_rb $1 = (struct branch_stack *) 0x0 (gdb) up 1148 intel_pt_reset_last_branch_rb(ptq); (gdb) l 1143 if (ret) 1144 pr_err("Intel Processor Trace: failed to deliver transaction event 1145 ret); 1146 1147 if (pt->synth_opts.callchain) 1148 intel_pt_reset_last_branch_rb(ptq); 1149 1150 return ret; 1151 } 1152 (gdb) p pt->synth_opts.callchain $2 = true (gdb) (gdb) bt #0 0x000000000054b58c in intel_pt_reset_last_branch_rb (ptq=0x1a36110) #1 0x000000000054c1e0 in intel_pt_synth_transaction_sample (ptq=0x1a36110) #2 0x000000000054c5b2 in intel_pt_sample (ptq=0x1a36110) Caused by checking the 'callchain' flag when it should have been the 'last_branch' flag. Fix that. Reported-by: Andi Kleen <[email protected]> Signed-off-by: Adrian Hunter <[email protected]> Cc: Jiri Olsa <[email protected]> Fixes: f14445e ("perf intel-pt: Support generating branch stack") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Aug 9, 2016
…CKING The log is as blow: ================================= [ INFO: inconsistent lock state ] 4.4.8+ #12 Not tainted --------------------------------- inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. kworker/u64:1/168 [HC0[0]:SC0[0]:HE1:SE1] takes: (&(&hisi_hba->lock)->rlock){?.....}, at: [<ffffffc00052c708>] alloc_dev_quirk_v2_hw+0x48/0xec {IN-HARDIRQ-W} state was registered at: [<ffffffc0000fc764>] mark_lock+0x19c/0x6a0 [<ffffffc0000fdc14>] __lock_acquire+0xa2c/0x1d00 [<ffffffc0000ff654>] lock_acquire+0x58/0x7c [<ffffffc0008b609c>] _raw_spin_lock_irqsave+0x54/0x6c [<ffffffc00052d3c0>] int_chnl_int_v2_hw+0x1c4/0x248 [<ffffffc0001098e8>] handle_irq_event_percpu+0x9c/0x144 [<ffffffc0001099d4>] handle_irq_event+0x44/0x74 [<ffffffc00010cd68>] handle_fasteoi_irq+0xb4/0x188 [<ffffffc000108ea8>] generic_handle_irq+0x24/0x38 [<ffffffc0001091fc>] __handle_domain_irq+0x60/0xac [<ffffffc00008261c>] gic_handle_irq+0xcc/0x168 [<ffffffc0000855ac>] el1_irq+0x6c/0xe0 [<ffffffc0000f7414>] default_idle_call+0x1c/0x34 [<ffffffc0000f7654>] cpu_startup_entry+0x1d4/0x228 [<ffffffc0008aecd8>] rest_init+0x150/0x160 [<ffffffc000c4b95c>] start_kernel+0x3a4/0x3b8 [<00000000008bb000>] 0x8bb000 irq event stamp: 32661 hardirqs last enabled at (32661): [<ffffffc0008b41a8>] __mutex_unlock_slowpath+0x108/0x18c hardirqs last disabled at (32660): [<ffffffc0008b40e4>] __mutex_unlock_slowpath+0x44/0x18c softirqs last enabled at (25114): [<ffffffc0000bde68>] __do_softirq+0x210/0x27c softirqs last disabled at (25095): [<ffffffc0000be224>] irq_exit+0x9c/0xe8 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&hisi_hba->lock)->rlock); <Interrupt> lock(&(&hisi_hba->lock)->rlock); *** DEADLOCK *** 2 locks held by kworker/u64:1/168: #0: ("%s"shost->work_q_name){++++.+}, at: [<ffffffc0000d2980>] process_one_work+0x134/0x3cc #1: ((&sw->work)#2){+.+.+.}, at: [<ffffffc0000d2980>] process_one_work+0x134/0x3cc stack backtrace: CPU: 4 PID: 168 Comm: kworker/u64:1 Not tainted 4.4.8+ #12 Hardware name: Huawei Technologies Co., Ltd. D03/D03, BIOS 1.12 01/01/1900 Workqueue: scsi_wq_1 sas_discover_domain Call trace: [<ffffffc000089988>] dump_backtrace+0x0/0x114 [<ffffffc000089ab0>] show_stack+0x14/0x1c [<ffffffc00035ac50>] dump_stack+0xb4/0xf0 [<ffffffc0000fc524>] print_usage_bug+0x210/0x2b4 [<ffffffc0000fcbc4>] mark_lock+0x5fc/0x6a0 [<ffffffc0000fd9e8>] __lock_acquire+0x800/0x1d00 [<ffffffc0000ff654>] lock_acquire+0x58/0x7c [<ffffffc0008b5edc>] _raw_spin_lock+0x44/0x58 [<ffffffc00052c708>] alloc_dev_quirk_v2_hw+0x48/0xec [<ffffffc000528214>] hisi_sas_dev_found+0x48/0x1b8 [<ffffffc00051a9b8>] sas_notify_lldd_dev_found+0x34/0xe0 [<ffffffc00051e5e8>] sas_discover_root_expander+0x58/0x128 [<ffffffc00051b38c>] sas_discover_domain+0x4bc/0x564 [<ffffffc0000d29ec>] process_one_work+0x1a0/0x3cc [<ffffffc0000d2d50>] worker_thread+0x138/0x438 [<ffffffc0000d9494>] kthread+0xdc/0xf0 [<ffffffc000085c50>] ret_from_fork+0x10/0x40 Signed-off-by: Wei Xu <[email protected]> Reviewed-by: John Garry <[email protected]>
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commit 6acfe68 upstream. Request-based DM's blk-mq support (dm-mq) was reported to be 50% slower than if an underlying null_blk device were used directly. One of the reasons for this drop in performance is that blk_insert_clone_request() was calling blk_mq_insert_request() with @async=true. This forced the use of kblockd_schedule_delayed_work_on() to run the blk-mq hw queues which ushered in ping-ponging between process context (fio in this case) and kblockd's kworker to submit the cloned request. The ftrace function_graph tracer showed: kworker-2013 => fio-12190 fio-12190 => kworker-2013 ... kworker-2013 => fio-12190 fio-12190 => kworker-2013 ... Fixing blk_insert_clone_request()'s blk_mq_insert_request() call to _not_ use kblockd to submit the cloned requests isn't enough to eliminate the observed context switches. In addition to this dm-mq specific blk-core fix, there are 2 DM core fixes to dm-mq that (when paired with the blk-core fix) completely eliminate the observed context switching: 1) don't blk_mq_run_hw_queues in blk-mq request completion Motivated by desire to reduce overhead of dm-mq, punting to kblockd just increases context switches. In my testing against a really fast null_blk device there was no benefit to running blk_mq_run_hw_queues() on completion (and no other blk-mq driver does this). So hopefully this change doesn't induce the need for yet another revert like commit 621739b ! 2) use blk_mq_complete_request() in dm_complete_request() blk_complete_request() doesn't offer the traditional q->mq_ops vs .request_fn branching pattern that other historic block interfaces do (e.g. blk_get_request). Using blk_mq_complete_request() for blk-mq requests is important for performance. It should be noted that, like blk_complete_request(), blk_mq_complete_request() doesn't natively handle partial completions -- but the request-based DM-multipath target does provide the required partial completion support by dm.c:end_clone_bio() triggering requeueing of the request via dm-mpath.c:multipath_end_io()'s return of DM_ENDIO_REQUEUE. dm-mq fix xin3liang#2 is _much_ more important than xin3liang#1 for eliminating the context switches. Before: cpu : usr=15.10%, sys=59.39%, ctx=7905181, majf=0, minf=475 After: cpu : usr=20.60%, sys=79.35%, ctx=2008, majf=0, minf=472 With these changes multithreaded async read IOPs improved from ~950K to ~1350K for this dm-mq stacked on null_blk test-case. The raw read IOPs of the underlying null_blk device for the same workload is ~1950K. Fixes: 7fb4898 ("block: add blk-mq support to blk_insert_cloned_request()") Fixes: bfebd1c ("dm: add full blk-mq support to request-based DM") Reported-by: Sagi Grimberg <[email protected]> Signed-off-by: Mike Snitzer <[email protected]> Acked-by: Jens Axboe <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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[ Upstream commit 9b36881 ] We need to update the skb->csum after pulling the skb, otherwise an unnecessary checksum (re)computation can ocure for IGMP/MLD packets in the bridge code. Additionally this fixes the following splats for network devices / bridge ports with support for and enabled RX checksum offloading: [...] [ 43.986968] eth0: hw csum failure [ 43.990344] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.4.0 xin3liang#2 [ 43.996193] Hardware name: BCM2709 [ 43.999647] [<800204e0>] (unwind_backtrace) from [<8001cf14>] (show_stack+0x10/0x14) [ 44.007432] [<8001cf14>] (show_stack) from [<801ab614>] (dump_stack+0x80/0x90) [ 44.014695] [<801ab614>] (dump_stack) from [<802e4548>] (__skb_checksum_complete+0x6c/0xac) [ 44.023090] [<802e4548>] (__skb_checksum_complete) from [<803a055c>] (ipv6_mc_validate_checksum+0x104/0x178) [ 44.032959] [<803a055c>] (ipv6_mc_validate_checksum) from [<802e111c>] (skb_checksum_trimmed+0x130/0x188) [ 44.042565] [<802e111c>] (skb_checksum_trimmed) from [<803a06e8>] (ipv6_mc_check_mld+0x118/0x338) [ 44.051501] [<803a06e8>] (ipv6_mc_check_mld) from [<803b2c98>] (br_multicast_rcv+0x5dc/0xd00) [ 44.060077] [<803b2c98>] (br_multicast_rcv) from [<803aa510>] (br_handle_frame_finish+0xac/0x51c) [...] Fixes: 9afd85c ("net: Export IGMP/MLD message validation code") Reported-by: Álvaro Fernández Rojas <[email protected]> Signed-off-by: Linus Lüssing <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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commit cf0a254 upstream. BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 1, irqs_disabled(): 128, pid: 383, name: sh Preemption disabled at:[<ffff800000124c18>] kgdb_cpu_enter+0x158/0x6b8 CPU: 3 PID: 383 Comm: sh Tainted: G W 4.1.13-rt13 xin3liang#2 Hardware name: Freescale Layerscape 2085a RDB Board (DT) Call trace: [<ffff8000000885e8>] dump_backtrace+0x0/0x128 [<ffff800000088734>] show_stack+0x24/0x30 [<ffff80000079a7c4>] dump_stack+0x80/0xa0 [<ffff8000000bd324>] ___might_sleep+0x18c/0x1a0 [<ffff8000007a20ac>] __rt_spin_lock+0x2c/0x40 [<ffff8000007a2268>] rt_read_lock+0x40/0x58 [<ffff800000085328>] single_step_handler+0x38/0xd8 [<ffff800000082368>] do_debug_exception+0x58/0xb8 Exception stack(0xffff80834a1e7c80 to 0xffff80834a1e7da0) 7c80: ffffff9c ffffffff 92c23ba0 0000ffff 4a1e7e4 ffff8083 001bfcc4 ffff8000 7ca0: f2000400 00000000 00000000 00000000 4a1e7d80 ffff8083 0049501c ffff8000 7cc0: 00005402 00000000 00aaa210 ffff8000 4a1e7ea0 ffff8083 000833f4 ffff8000 7ce0: ffffff9c ffffffff 92c23ba0 0000ffff 4a1e7ea0 ffff8083 001bfcc0 ffff8000 7d00: 4a0fc400 ffff8083 00005402 00000000 4a1e7d40 ffff8083 00490324 ffff8000 7d20: ffffff9c 00000000 92c23ba0 0000ffff 000a0000 00000000 00000000 00000000 7d40: 00000008 00000000 00080000 00000000 92c23b8 0000ffff 92c23b8e 0000ffff 7d60: 00000038 00000000 00001cb2 00000000 00000005 00000000 92d7b498 0000ffff 7d80: 01010101 01010101 92be9000 0000ffff 00000000 00000000 00000030 00000000 [<ffff8000000833f4>] el1_dbg+0x18/0x6c This issue is similar with 62c6c61("arm64: replace read_lock to rcu lock in call_break_hook"), but comes to single_step_handler. This also solves kgdbts boot test silent hang issue on 4.4 -rt kernel. Signed-off-by: Yang Shi <[email protected]> Acked-by: Will Deacon <[email protected]> Signed-off-by: Catalin Marinas <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Aug 17, 2016
commit b49b927 upstream. We shouldn't be calling clk_prepare_enable()/clk_prepare_disable() in an atomic context. Fixes the following issue: [ 5.830970] ehci-omap: OMAP-EHCI Host Controller driver [ 5.830974] driver_register 'ehci-omap' [ 5.895849] driver_register 'wl1271_sdio' [ 5.896870] BUG: scheduling while atomic: udevd/994/0x00000002 [ 5.896876] 4 locks held by udevd/994: [ 5.896904] #0: (&dev->mutex){......}, at: [<c049597c>] __driver_attach+0x60/0xac [ 5.896923] xin3liang#1: (&dev->mutex){......}, at: [<c049598c>] __driver_attach+0x70/0xac [ 5.896946] xin3liang#2: (tll_lock){+.+...}, at: [<c04c2630>] omap_tll_enable+0x2c/0xd0 [ 5.896966] xin3liang#3: (prepare_lock){+.+...}, at: [<c05ce9c8>] clk_prepare_lock+0x48/0xe0 [ 5.897042] Modules linked in: wlcore_sdio(+) ehci_omap(+) dwc3_omap snd_soc_ts3a225e leds_is31fl319x bq27xxx_battery_i2c tsc2007 bq27xxx_battery bq2429x_charger ina2xx tca8418_keypad as5013 leds_tca6507 twl6040_vibra gpio_twl6040 bmp085_i2c(+) palmas_gpadc usb3503 palmas_pwrbutton bmg160_i2c(+) bmp085 bma150(+) bmg160_core bmp280 input_polldev snd_soc_omap_mcbsp snd_soc_omap_mcpdm snd_soc_omap snd_pcm_dmaengine [ 5.897048] Preemption disabled at:[< (null)>] (null) [ 5.897051] [ 5.897059] CPU: 0 PID: 994 Comm: udevd Not tainted 4.6.0-rc5-letux+ torvalds#233 [ 5.897062] Hardware name: Generic OMAP5 (Flattened Device Tree) [ 5.897076] [<c010e714>] (unwind_backtrace) from [<c010af34>] (show_stack+0x10/0x14) [ 5.897087] [<c010af34>] (show_stack) from [<c040aa7c>] (dump_stack+0x88/0xc0) [ 5.897099] [<c040aa7c>] (dump_stack) from [<c020c558>] (__schedule_bug+0xac/0xd0) [ 5.897111] [<c020c558>] (__schedule_bug) from [<c06f3d44>] (__schedule+0x88/0x7e4) [ 5.897120] [<c06f3d44>] (__schedule) from [<c06f46d8>] (schedule+0x9c/0xc0) [ 5.897129] [<c06f46d8>] (schedule) from [<c06f4904>] (schedule_preempt_disabled+0x14/0x20) [ 5.897140] [<c06f4904>] (schedule_preempt_disabled) from [<c06f64e4>] (mutex_lock_nested+0x258/0x43c) [ 5.897150] [<c06f64e4>] (mutex_lock_nested) from [<c05ce9c8>] (clk_prepare_lock+0x48/0xe0) [ 5.897160] [<c05ce9c8>] (clk_prepare_lock) from [<c05d0e7c>] (clk_prepare+0x10/0x28) [ 5.897169] [<c05d0e7c>] (clk_prepare) from [<c04c2668>] (omap_tll_enable+0x64/0xd0) [ 5.897180] [<c04c2668>] (omap_tll_enable) from [<c04c1728>] (usbhs_runtime_resume+0x18/0x17c) [ 5.897192] [<c04c1728>] (usbhs_runtime_resume) from [<c049d404>] (pm_generic_runtime_resume+0x2c/0x40) [ 5.897202] [<c049d404>] (pm_generic_runtime_resume) from [<c049f180>] (__rpm_callback+0x38/0x68) [ 5.897210] [<c049f180>] (__rpm_callback) from [<c049f220>] (rpm_callback+0x70/0x88) [ 5.897218] [<c049f220>] (rpm_callback) from [<c04a0a00>] (rpm_resume+0x4ec/0x7ec) [ 5.897227] [<c04a0a00>] (rpm_resume) from [<c04a0f48>] (__pm_runtime_resume+0x4c/0x64) [ 5.897236] [<c04a0f48>] (__pm_runtime_resume) from [<c04958dc>] (driver_probe_device+0x30/0x70) [ 5.897246] [<c04958dc>] (driver_probe_device) from [<c04959a4>] (__driver_attach+0x88/0xac) [ 5.897256] [<c04959a4>] (__driver_attach) from [<c04940f8>] (bus_for_each_dev+0x50/0x84) [ 5.897267] [<c04940f8>] (bus_for_each_dev) from [<c0494e40>] (bus_add_driver+0xcc/0x1e4) [ 5.897276] [<c0494e40>] (bus_add_driver) from [<c0496914>] (driver_register+0xac/0xf4) [ 5.897286] [<c0496914>] (driver_register) from [<c01018e0>] (do_one_initcall+0x100/0x1b8) [ 5.897296] [<c01018e0>] (do_one_initcall) from [<c01c7a54>] (do_init_module+0x58/0x1c0) [ 5.897304] [<c01c7a54>] (do_init_module) from [<c01c8a3c>] (SyS_finit_module+0x88/0x90) [ 5.897313] [<c01c8a3c>] (SyS_finit_module) from [<c0107120>] (ret_fast_syscall+0x0/0x1c) [ 5.912697] ------------[ cut here ]------------ [ 5.912711] WARNING: CPU: 0 PID: 994 at kernel/sched/core.c:2996 _raw_spin_unlock+0x28/0x58 [ 5.912717] DEBUG_LOCKS_WARN_ON(val > preempt_count()) Reported-by: H. Nikolaus Schaller <[email protected]> Tested-by: H. Nikolaus Schaller <[email protected]> Signed-off-by: Roger Quadros <[email protected]> Signed-off-by: Lee Jones <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Aug 17, 2016
commit 8e96a87 upstream. Userspace can quite legitimately perform an exec() syscall with a suspended transaction. exec() does not return to the old process, rather it load a new one and starts that, the expectation therefore is that the new process starts not in a transaction. Currently exec() is not treated any differently to any other syscall which creates problems. Firstly it could allow a new process to start with a suspended transaction for a binary that no longer exists. This means that the checkpointed state won't be valid and if the suspended transaction were ever to be resumed and subsequently aborted (a possibility which is exceedingly likely as exec()ing will likely doom the transaction) the new process will jump to invalid state. Secondly the incorrect attempt to keep the transactional state while still zeroing state for the new process creates at least two TM Bad Things. The first triggers on the rfid to return to userspace as start_thread() has given the new process a 'clean' MSR but the suspend will still be set in the hardware MSR. The second TM Bad Thing triggers in __switch_to() as the processor is still transactionally suspended but __switch_to() wants to zero the TM sprs for the new process. This is an example of the outcome of calling exec() with a suspended transaction. Note the first 700 is likely the first TM bad thing decsribed earlier only the kernel can't report it as we've loaded userspace registers. c000000000009980 is the rfid in fast_exception_return() Bad kernel stack pointer 3fffcfa1a370 at c000000000009980 Oops: Bad kernel stack pointer, sig: 6 [xin3liang#1] CPU: 0 PID: 2006 Comm: tm-execed Not tainted NIP: c000000000009980 LR: 0000000000000000 CTR: 0000000000000000 REGS: c00000003ffefd40 TRAP: 0700 Not tainted MSR: 8000000300201031 <SF,ME,IR,DR,LE,TM[SE]> CR: 00000000 XER: 00000000 CFAR: c0000000000098b4 SOFTE: 0 PACATMSCRATCH: b00000010000d033 GPR00: 0000000000000000 00003fffcfa1a370 0000000000000000 0000000000000000 GPR04: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR12: 00003fff966611c0 0000000000000000 0000000000000000 0000000000000000 NIP [c000000000009980] fast_exception_return+0xb0/0xb8 LR [0000000000000000] (null) Call Trace: Instruction dump: f84d0278 e9a100d8 7c7b03a6 e84101a0 7c4ff120 e8410170 7c5a03a6 e8010070 e8410080 e8610088 e8810090 e8210078 <4c000024> 48000000 e8610178 88ed023b Kernel BUG at c000000000043e80 [verbose debug info unavailable] Unexpected TM Bad Thing exception at c000000000043e80 (msr 0x201033) Oops: Unrecoverable exception, sig: 6 [xin3liang#2] CPU: 0 PID: 2006 Comm: tm-execed Tainted: G D task: c0000000fbea6d80 ti: c00000003ffec000 task.ti: c0000000fb7ec000 NIP: c000000000043e80 LR: c000000000015a24 CTR: 0000000000000000 REGS: c00000003ffef7e0 TRAP: 0700 Tainted: G D MSR: 8000000300201033 <SF,ME,IR,DR,RI,LE,TM[SE]> CR: 28002828 XER: 00000000 CFAR: c000000000015a20 SOFTE: 0 PACATMSCRATCH: b00000010000d033 GPR00: 0000000000000000 c00000003ffefa60 c000000000db5500 c0000000fbead000 GPR04: 8000000300001033 2222222222222222 2222222222222222 00000000ff160000 GPR08: 0000000000000000 800000010000d033 c0000000fb7e3ea0 c00000000fe00004 GPR12: 0000000000002200 c00000000fe00000 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 c0000000fbea7410 00000000ff160000 GPR24: c0000000ffe1f600 c0000000fbea8700 c0000000fbea8700 c0000000fbead000 GPR28: c000000000e20198 c0000000fbea6d80 c0000000fbeab680 c0000000fbea6d80 NIP [c000000000043e80] tm_restore_sprs+0xc/0x1c LR [c000000000015a24] __switch_to+0x1f4/0x420 Call Trace: Instruction dump: 7c800164 4e800020 7c0022a6 f80304a8 7c0222a6 f80304b0 7c0122a6 f80304b8 4e800020 e80304a8 7c0023a e80304b0 <7c0223a6> e80304b8 7c0123a6 4e800020 This fixes CVE-2016-5828. Fixes: bc2a940 ("powerpc: Hook in new transactional memory code") Signed-off-by: Cyril Bur <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Signed-off-by: kongxinwei [email protected]