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etnperlong wants to merge 111 commits into
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etnperlong:dev/hyperos
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HyperOS variant#8
etnperlong wants to merge 111 commits into
onettboots:saaya1from
etnperlong:dev/hyperos

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  • rebase dev/miui branch
  • Compatible with HyperOS A14 build

etnperlong and others added 30 commits March 1, 2024 23:42
Since we have no commit b93b016
("page cache: use xa_lock"), xarray.h isn't included to the
include/linux/fs.h.

For now, let's just add it to the files that needed for simpler fix.
Signed-off-by: Nauval Rizky <enuma.alrizky@gmail.com>
Fixes following error:
../fs/erofs/decompressor.c:226:9: error: implicit declaration of function 'LZ4_decompress_safe_partial' [-Werror,-Wimplicit-function-declaration]
                ret = LZ4_decompress_safe_partial(src + inputmargin, out,
                      ^

Change-Id: I4eb111456d755154492dd8918866a53c38682ebd
Signed-off-by: UtsavBalar1231 <utsavbalar1231@gmail.com>
Signed-off-by: Stephen Xian <stevexian56@gmail.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
onettboots and others added 21 commits March 2, 2024 00:00
Signed-off-by: onettboots <blackcocopet@gmail.com>
Change-Id: If6245ce53ed742377ecd2eb53f1debe5fb5a21c8
Signed-off-by: penglezos <panagiotisegl@gmail.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
PCC cannot be applied per-plane, but CSC can. Translate PCC to CSC
to allow skipping it for some planes.

Change-Id: I76fa04fed6bcc9426cf2a38c58c23e49e27b8750

[@RealJohnGalt] adapt for k4.14

Signed-off-by: onettboots <blackcocopet@gmail.com>
FOD performance decreases if the color of the icon is not
exactly white, which happens when night light is enabled.
Skip CSC for the FOD layer.

Change-Id: Icb202690ec58e807b612fffe479c8e7c5c3b5d03
Signed-off-by: onettboots <blackcocopet@gmail.com>
../drivers/gpu/drm/msm/sde/sde_color_processing.c:892:9: error: incompatible pointer types returning 'unsigned char *' from a function with result type 'struct drm_msm_pcc *' [-Werror,-Wincompatible-pointer-types] return blob ? blob->data : NULL; ^~~~~~~~ 1 error generated.

Signed-off-by: onettboots <blackcocopet@gmail.com>
Signed-off-by: penglezos <panagiotisegl@gmail.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
Change-Id: I76f61f7de1637bd70c65a684468d41f24b03e15c
Signed-off-by: penglezos <panagiotisegl@gmail.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
this source using old fod for penglezos trees / lineage os rom

Signed-off-by: onettboots <blackcocopet@gmail.com>
Change-Id: I2a5d47eaf951cb04c92921518e93dd2ba4708fd3
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
Some architectures support the accessed bit in non-leaf PMD entries,
e.g., x86 sets the accessed bit in a non-leaf PMD entry when using it
as part of linear address translation [1]. Page table walkers that
clear the accessed bit may use this capability to reduce their search
space.

Note that:
1. Although an inline function is preferable, this capability is added
   as a configuration option for consistency with the existing macros.
2. Due to the little interest in other varieties, this capability was
   only tested on Intel and AMD CPUs.

[1]: Intel 64 and IA-32 Architectures Software Developer's Manual
     Volume 3 (June 2021), section 4.8

Link: https://lore.kernel.org/r/20220309021230.721028-3-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I73f84a21fd315192eaa3e6443334ed1bccb4e99e
Signed-off-by: 0wnerDied <z1281552865@gmail.com>
Change-Id: Ibc8087ded16d22bb368ce8c3f10f9e1d79ae03fa
Signed-off-by: Julian Liu <wlootlxt123@gmail.com>
onettboots pushed a commit that referenced this pull request Jun 12, 2024
[ Upstream commit f8bbc07ac535593139c875ffa19af924b1084540 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 68459b8e3ee554ce71878af9eb69659b9462c588)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
onettboots pushed a commit that referenced this pull request Jul 24, 2024
[ Upstream commit ffbf4fb9b5c12ff878a10ea17997147ea4ebea6f ]

When CONFIG_DEBUG_BUGVERBOSE=n, we fail to add necessary padding bytes
to bug_table entries, and as a result the last entry in a bug table will
be ignored, potentially leading to an unexpected panic(). All prior
entries in the table will be handled correctly.

The arm64 ABI requires that struct fields of up to 8 bytes are
naturally-aligned, with padding added within a struct such that struct
are suitably aligned within arrays.

When CONFIG_DEBUG_BUGVERPOSE=y, the layout of a bug_entry is:

	struct bug_entry {
		signed int      bug_addr_disp;	// 4 bytes
		signed int      file_disp;	// 4 bytes
		unsigned short  line;		// 2 bytes
		unsigned short  flags;		// 2 bytes
	}

... with 12 bytes total, requiring 4-byte alignment.

When CONFIG_DEBUG_BUGVERBOSE=n, the layout of a bug_entry is:

	struct bug_entry {
		signed int      bug_addr_disp;	// 4 bytes
		unsigned short  flags;		// 2 bytes
		< implicit padding >		// 2 bytes
	}

... with 8 bytes total, with 6 bytes of data and 2 bytes of trailing
padding, requiring 4-byte alginment.

When we create a bug_entry in assembly, we align the start of the entry
to 4 bytes, which implicitly handles padding for any prior entries.
However, we do not align the end of the entry, and so when
CONFIG_DEBUG_BUGVERBOSE=n, the final entry lacks the trailing padding
bytes.

For the main kernel image this is not a problem as find_bug() doesn't
depend on the trailing padding bytes when searching for entries:

	for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
		if (bugaddr == bug_addr(bug))
			return bug;

However for modules, module_bug_finalize() depends on the trailing
bytes when calculating the number of entries:

	mod->num_bugs = sechdrs[i].sh_size / sizeof(struct bug_entry);

... and as the last bug_entry lacks the necessary padding bytes, this entry
will not be counted, e.g. in the case of a single entry:

	sechdrs[i].sh_size == 6
	sizeof(struct bug_entry) == 8;

	sechdrs[i].sh_size / sizeof(struct bug_entry) == 0;

Consequently module_find_bug() will miss the last bug_entry when it does:

	for (i = 0; i < mod->num_bugs; ++i, ++bug)
		if (bugaddr == bug_addr(bug))
			goto out;

... which can lead to a kenrel panic due to an unhandled bug.

This can be demonstrated with the following module:

	static int __init buginit(void)
	{
		WARN(1, "hello\n");
		return 0;
	}

	static void __exit bugexit(void)
	{
	}

	module_init(buginit);
	module_exit(bugexit);
	MODULE_LICENSE("GPL");

... which will trigger a kernel panic when loaded:

	------------[ cut here ]------------
	hello
	Unexpected kernel BRK exception at EL1
	Internal error: BRK handler: 00000000f2000800 [#1] PREEMPT SMP
	Modules linked in: hello(O+)
	CPU: 0 PID: 50 Comm: insmod Tainted: G           O       6.9.1 #8
	Hardware name: linux,dummy-virt (DT)
	pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
	pc : buginit+0x18/0x1000 [hello]
	lr : buginit+0x18/0x1000 [hello]
	sp : ffff800080533ae0
	x29: ffff800080533ae0 x28: 0000000000000000 x27: 0000000000000000
	x26: ffffaba8c4e70510 x25: ffff800080533c30 x24: ffffaba8c4a28a58
	x23: 0000000000000000 x22: 0000000000000000 x21: ffff3947c0eab3c0
	x20: ffffaba8c4e3f000 x19: ffffaba846464000 x18: 0000000000000006
	x17: 0000000000000000 x16: ffffaba8c2492834 x15: 0720072007200720
	x14: 0720072007200720 x13: ffffaba8c49b27c8 x12: 0000000000000312
	x11: 0000000000000106 x10: ffffaba8c4a0a7c8 x9 : ffffaba8c49b27c8
	x8 : 00000000ffffefff x7 : ffffaba8c4a0a7c8 x6 : 80000000fffff000
	x5 : 0000000000000107 x4 : 0000000000000000 x3 : 0000000000000000
	x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff3947c0eab3c0
	Call trace:
	 buginit+0x18/0x1000 [hello]
	 do_one_initcall+0x80/0x1c8
	 do_init_module+0x60/0x218
	 load_module+0x1ba4/0x1d70
	 __do_sys_init_module+0x198/0x1d0
	 __arm64_sys_init_module+0x1c/0x28
	 invoke_syscall+0x48/0x114
	 el0_svc_common.constprop.0+0x40/0xe0
	 do_el0_svc+0x1c/0x28
	 el0_svc+0x34/0xd8
	 el0t_64_sync_handler+0x120/0x12c
	 el0t_64_sync+0x190/0x194
	Code: d0ffffe0 910003fd 91000000 9400000b (d4210000)
	---[ end trace 0000000000000000 ]---
	Kernel panic - not syncing: BRK handler: Fatal exception

Fix this by always aligning the end of a bug_entry to 4 bytes, which is
correct regardless of CONFIG_DEBUG_BUGVERBOSE.

Fixes: 9fb7410 ("arm64/BUG: Use BRK instruction for generic BUG traps")

Signed-off-by: Yuanbin Xie <xieyuanbin1@huawei.com>
Signed-off-by: Jiangfeng Xiao <xiaojiangfeng@huawei.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1716212077-43826-1-git-send-email-xiaojiangfeng@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit f221bd58db0f6ca087ac0392284f6bce21f4f8ea)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
onettboots pushed a commit that referenced this pull request Feb 11, 2025
…le_direct_reclaim()

commit 6aaced5abd32e2a57cd94fd64f824514d0361da8 upstream.

The task sometimes continues looping in throttle_direct_reclaim() because
allow_direct_reclaim(pgdat) keeps returning false.

 #0 [ffff80002cb6f8d0] __switch_to at ffff8000080095ac
 #1 [ffff80002cb6f900] __schedule at ffff800008abbd1c
 #2 [ffff80002cb6f990] schedule at ffff800008abc50c
 #3 [ffff80002cb6f9b0] throttle_direct_reclaim at ffff800008273550
 #4 [ffff80002cb6fa20] try_to_free_pages at ffff800008277b68
 #5 [ffff80002cb6fae0] __alloc_pages_nodemask at ffff8000082c4660
 #6 [ffff80002cb6fc50] alloc_pages_vma at ffff8000082e4a98
 #7 [ffff80002cb6fca0] do_anonymous_page at ffff80000829f5a8
 #8 [ffff80002cb6fce0] __handle_mm_fault at ffff8000082a5974
 #9 [ffff80002cb6fd90] handle_mm_fault at ffff8000082a5bd4

At this point, the pgdat contains the following two zones:

        NODE: 4  ZONE: 0  ADDR: ffff00817fffe540  NAME: "DMA32"
          SIZE: 20480  MIN/LOW/HIGH: 11/28/45
          VM_STAT:
                NR_FREE_PAGES: 359
        NR_ZONE_INACTIVE_ANON: 18813
          NR_ZONE_ACTIVE_ANON: 0
        NR_ZONE_INACTIVE_FILE: 50
          NR_ZONE_ACTIVE_FILE: 0
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

        NODE: 4  ZONE: 1  ADDR: ffff00817fffec00  NAME: "Normal"
          SIZE: 8454144  PRESENT: 98304  MIN/LOW/HIGH: 68/166/264
          VM_STAT:
                NR_FREE_PAGES: 146
        NR_ZONE_INACTIVE_ANON: 94668
          NR_ZONE_ACTIVE_ANON: 3
        NR_ZONE_INACTIVE_FILE: 735
          NR_ZONE_ACTIVE_FILE: 78
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

In allow_direct_reclaim(), while processing ZONE_DMA32, the sum of
inactive/active file-backed pages calculated in zone_reclaimable_pages()
based on the result of zone_page_state_snapshot() is zero.

Additionally, since this system lacks swap, the calculation of inactive/
active anonymous pages is skipped.

        crash> p nr_swap_pages
        nr_swap_pages = $1937 = {
          counter = 0
        }

As a result, ZONE_DMA32 is deemed unreclaimable and skipped, moving on to
the processing of the next zone, ZONE_NORMAL, despite ZONE_DMA32 having
free pages significantly exceeding the high watermark.

The problem is that the pgdat->kswapd_failures hasn't been incremented.

        crash> px ((struct pglist_data *) 0xffff00817fffe540)->kswapd_failures
        $1935 = 0x0

This is because the node deemed balanced.  The node balancing logic in
balance_pgdat() evaluates all zones collectively.  If one or more zones
(e.g., ZONE_DMA32) have enough free pages to meet their watermarks, the
entire node is deemed balanced.  This causes balance_pgdat() to exit early
before incrementing the kswapd_failures, as it considers the overall
memory state acceptable, even though some zones (like ZONE_NORMAL) remain
under significant pressure.

The patch ensures that zone_reclaimable_pages() includes free pages
(NR_FREE_PAGES) in its calculation when no other reclaimable pages are
available (e.g., file-backed or anonymous pages).  This change prevents
zones like ZONE_DMA32, which have sufficient free pages, from being
mistakenly deemed unreclaimable.  By doing so, the patch ensures proper
node balancing, avoids masking pressure on other zones like ZONE_NORMAL,
and prevents infinite loops in throttle_direct_reclaim() caused by
allow_direct_reclaim(pgdat) repeatedly returning false.

The kernel hangs due to a task stuck in throttle_direct_reclaim(), caused
by a node being incorrectly deemed balanced despite pressure in certain
zones, such as ZONE_NORMAL.  This issue arises from
zone_reclaimable_pages() returning 0 for zones without reclaimable file-
backed or anonymous pages, causing zones like ZONE_DMA32 with sufficient
free pages to be skipped.

The lack of swap or reclaimable pages results in ZONE_DMA32 being ignored
during reclaim, masking pressure in other zones.  Consequently,
pgdat->kswapd_failures remains 0 in balance_pgdat(), preventing fallback
mechanisms in allow_direct_reclaim() from being triggered, leading to an
infinite loop in throttle_direct_reclaim().

This patch modifies zone_reclaimable_pages() to account for free pages
(NR_FREE_PAGES) when no other reclaimable pages exist.  This ensures zones
with sufficient free pages are not skipped, enabling proper balancing and
reclaim behavior.

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20241130164346.436469-1-snishika@redhat.com
Link: https://lkml.kernel.org/r/20241130161236.433747-2-snishika@redhat.com
Fixes: 5a1c84b ("mm: remove reclaim and compaction retry approximations")
Signed-off-by: Seiji Nishikawa <snishika@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>
Signed-off-by: onettboots <blackcocopet@gmail.com>
onettboots pushed a commit that referenced this pull request Feb 13, 2025
…le_direct_reclaim()

commit 6aaced5abd32e2a57cd94fd64f824514d0361da8 upstream.

The task sometimes continues looping in throttle_direct_reclaim() because
allow_direct_reclaim(pgdat) keeps returning false.

 #0 [ffff80002cb6f8d0] __switch_to at ffff8000080095ac
 #1 [ffff80002cb6f900] __schedule at ffff800008abbd1c
 #2 [ffff80002cb6f990] schedule at ffff800008abc50c
 #3 [ffff80002cb6f9b0] throttle_direct_reclaim at ffff800008273550
 #4 [ffff80002cb6fa20] try_to_free_pages at ffff800008277b68
 #5 [ffff80002cb6fae0] __alloc_pages_nodemask at ffff8000082c4660
 #6 [ffff80002cb6fc50] alloc_pages_vma at ffff8000082e4a98
 #7 [ffff80002cb6fca0] do_anonymous_page at ffff80000829f5a8
 #8 [ffff80002cb6fce0] __handle_mm_fault at ffff8000082a5974
 #9 [ffff80002cb6fd90] handle_mm_fault at ffff8000082a5bd4

At this point, the pgdat contains the following two zones:

        NODE: 4  ZONE: 0  ADDR: ffff00817fffe540  NAME: "DMA32"
          SIZE: 20480  MIN/LOW/HIGH: 11/28/45
          VM_STAT:
                NR_FREE_PAGES: 359
        NR_ZONE_INACTIVE_ANON: 18813
          NR_ZONE_ACTIVE_ANON: 0
        NR_ZONE_INACTIVE_FILE: 50
          NR_ZONE_ACTIVE_FILE: 0
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

        NODE: 4  ZONE: 1  ADDR: ffff00817fffec00  NAME: "Normal"
          SIZE: 8454144  PRESENT: 98304  MIN/LOW/HIGH: 68/166/264
          VM_STAT:
                NR_FREE_PAGES: 146
        NR_ZONE_INACTIVE_ANON: 94668
          NR_ZONE_ACTIVE_ANON: 3
        NR_ZONE_INACTIVE_FILE: 735
          NR_ZONE_ACTIVE_FILE: 78
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

In allow_direct_reclaim(), while processing ZONE_DMA32, the sum of
inactive/active file-backed pages calculated in zone_reclaimable_pages()
based on the result of zone_page_state_snapshot() is zero.

Additionally, since this system lacks swap, the calculation of inactive/
active anonymous pages is skipped.

        crash> p nr_swap_pages
        nr_swap_pages = $1937 = {
          counter = 0
        }

As a result, ZONE_DMA32 is deemed unreclaimable and skipped, moving on to
the processing of the next zone, ZONE_NORMAL, despite ZONE_DMA32 having
free pages significantly exceeding the high watermark.

The problem is that the pgdat->kswapd_failures hasn't been incremented.

        crash> px ((struct pglist_data *) 0xffff00817fffe540)->kswapd_failures
        $1935 = 0x0

This is because the node deemed balanced.  The node balancing logic in
balance_pgdat() evaluates all zones collectively.  If one or more zones
(e.g., ZONE_DMA32) have enough free pages to meet their watermarks, the
entire node is deemed balanced.  This causes balance_pgdat() to exit early
before incrementing the kswapd_failures, as it considers the overall
memory state acceptable, even though some zones (like ZONE_NORMAL) remain
under significant pressure.

The patch ensures that zone_reclaimable_pages() includes free pages
(NR_FREE_PAGES) in its calculation when no other reclaimable pages are
available (e.g., file-backed or anonymous pages).  This change prevents
zones like ZONE_DMA32, which have sufficient free pages, from being
mistakenly deemed unreclaimable.  By doing so, the patch ensures proper
node balancing, avoids masking pressure on other zones like ZONE_NORMAL,
and prevents infinite loops in throttle_direct_reclaim() caused by
allow_direct_reclaim(pgdat) repeatedly returning false.

The kernel hangs due to a task stuck in throttle_direct_reclaim(), caused
by a node being incorrectly deemed balanced despite pressure in certain
zones, such as ZONE_NORMAL.  This issue arises from
zone_reclaimable_pages() returning 0 for zones without reclaimable file-
backed or anonymous pages, causing zones like ZONE_DMA32 with sufficient
free pages to be skipped.

The lack of swap or reclaimable pages results in ZONE_DMA32 being ignored
during reclaim, masking pressure in other zones.  Consequently,
pgdat->kswapd_failures remains 0 in balance_pgdat(), preventing fallback
mechanisms in allow_direct_reclaim() from being triggered, leading to an
infinite loop in throttle_direct_reclaim().

This patch modifies zone_reclaimable_pages() to account for free pages
(NR_FREE_PAGES) when no other reclaimable pages exist.  This ensures zones
with sufficient free pages are not skipped, enabling proper balancing and
reclaim behavior.

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20241130164346.436469-1-snishika@redhat.com
Link: https://lkml.kernel.org/r/20241130161236.433747-2-snishika@redhat.com
Fixes: 5a1c84b ("mm: remove reclaim and compaction retry approximations")
Signed-off-by: Seiji Nishikawa <snishika@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>
Signed-off-by: onettboots <blackcocopet@gmail.com>
onettboots pushed a commit that referenced this pull request Feb 13, 2025
…le_direct_reclaim()

commit 6aaced5abd32e2a57cd94fd64f824514d0361da8 upstream.

The task sometimes continues looping in throttle_direct_reclaim() because
allow_direct_reclaim(pgdat) keeps returning false.

 #0 [ffff80002cb6f8d0] __switch_to at ffff8000080095ac
 #1 [ffff80002cb6f900] __schedule at ffff800008abbd1c
 #2 [ffff80002cb6f990] schedule at ffff800008abc50c
 #3 [ffff80002cb6f9b0] throttle_direct_reclaim at ffff800008273550
 #4 [ffff80002cb6fa20] try_to_free_pages at ffff800008277b68
 #5 [ffff80002cb6fae0] __alloc_pages_nodemask at ffff8000082c4660
 #6 [ffff80002cb6fc50] alloc_pages_vma at ffff8000082e4a98
 #7 [ffff80002cb6fca0] do_anonymous_page at ffff80000829f5a8
 #8 [ffff80002cb6fce0] __handle_mm_fault at ffff8000082a5974
 #9 [ffff80002cb6fd90] handle_mm_fault at ffff8000082a5bd4

At this point, the pgdat contains the following two zones:

        NODE: 4  ZONE: 0  ADDR: ffff00817fffe540  NAME: "DMA32"
          SIZE: 20480  MIN/LOW/HIGH: 11/28/45
          VM_STAT:
                NR_FREE_PAGES: 359
        NR_ZONE_INACTIVE_ANON: 18813
          NR_ZONE_ACTIVE_ANON: 0
        NR_ZONE_INACTIVE_FILE: 50
          NR_ZONE_ACTIVE_FILE: 0
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

        NODE: 4  ZONE: 1  ADDR: ffff00817fffec00  NAME: "Normal"
          SIZE: 8454144  PRESENT: 98304  MIN/LOW/HIGH: 68/166/264
          VM_STAT:
                NR_FREE_PAGES: 146
        NR_ZONE_INACTIVE_ANON: 94668
          NR_ZONE_ACTIVE_ANON: 3
        NR_ZONE_INACTIVE_FILE: 735
          NR_ZONE_ACTIVE_FILE: 78
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

In allow_direct_reclaim(), while processing ZONE_DMA32, the sum of
inactive/active file-backed pages calculated in zone_reclaimable_pages()
based on the result of zone_page_state_snapshot() is zero.

Additionally, since this system lacks swap, the calculation of inactive/
active anonymous pages is skipped.

        crash> p nr_swap_pages
        nr_swap_pages = $1937 = {
          counter = 0
        }

As a result, ZONE_DMA32 is deemed unreclaimable and skipped, moving on to
the processing of the next zone, ZONE_NORMAL, despite ZONE_DMA32 having
free pages significantly exceeding the high watermark.

The problem is that the pgdat->kswapd_failures hasn't been incremented.

        crash> px ((struct pglist_data *) 0xffff00817fffe540)->kswapd_failures
        $1935 = 0x0

This is because the node deemed balanced.  The node balancing logic in
balance_pgdat() evaluates all zones collectively.  If one or more zones
(e.g., ZONE_DMA32) have enough free pages to meet their watermarks, the
entire node is deemed balanced.  This causes balance_pgdat() to exit early
before incrementing the kswapd_failures, as it considers the overall
memory state acceptable, even though some zones (like ZONE_NORMAL) remain
under significant pressure.

The patch ensures that zone_reclaimable_pages() includes free pages
(NR_FREE_PAGES) in its calculation when no other reclaimable pages are
available (e.g., file-backed or anonymous pages).  This change prevents
zones like ZONE_DMA32, which have sufficient free pages, from being
mistakenly deemed unreclaimable.  By doing so, the patch ensures proper
node balancing, avoids masking pressure on other zones like ZONE_NORMAL,
and prevents infinite loops in throttle_direct_reclaim() caused by
allow_direct_reclaim(pgdat) repeatedly returning false.

The kernel hangs due to a task stuck in throttle_direct_reclaim(), caused
by a node being incorrectly deemed balanced despite pressure in certain
zones, such as ZONE_NORMAL.  This issue arises from
zone_reclaimable_pages() returning 0 for zones without reclaimable file-
backed or anonymous pages, causing zones like ZONE_DMA32 with sufficient
free pages to be skipped.

The lack of swap or reclaimable pages results in ZONE_DMA32 being ignored
during reclaim, masking pressure in other zones.  Consequently,
pgdat->kswapd_failures remains 0 in balance_pgdat(), preventing fallback
mechanisms in allow_direct_reclaim() from being triggered, leading to an
infinite loop in throttle_direct_reclaim().

This patch modifies zone_reclaimable_pages() to account for free pages
(NR_FREE_PAGES) when no other reclaimable pages exist.  This ensures zones
with sufficient free pages are not skipped, enabling proper balancing and
reclaim behavior.

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20241130164346.436469-1-snishika@redhat.com
Link: https://lkml.kernel.org/r/20241130161236.433747-2-snishika@redhat.com
Fixes: 5a1c84b ("mm: remove reclaim and compaction retry approximations")
Signed-off-by: Seiji Nishikawa <snishika@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>
Signed-off-by: onettboots <blackcocopet@gmail.com>
onettboots pushed a commit that referenced this pull request Feb 14, 2025
…le_direct_reclaim()

commit 6aaced5abd32e2a57cd94fd64f824514d0361da8 upstream.

The task sometimes continues looping in throttle_direct_reclaim() because
allow_direct_reclaim(pgdat) keeps returning false.

 #0 [ffff80002cb6f8d0] __switch_to at ffff8000080095ac
 #1 [ffff80002cb6f900] __schedule at ffff800008abbd1c
 #2 [ffff80002cb6f990] schedule at ffff800008abc50c
 #3 [ffff80002cb6f9b0] throttle_direct_reclaim at ffff800008273550
 #4 [ffff80002cb6fa20] try_to_free_pages at ffff800008277b68
 #5 [ffff80002cb6fae0] __alloc_pages_nodemask at ffff8000082c4660
 #6 [ffff80002cb6fc50] alloc_pages_vma at ffff8000082e4a98
 #7 [ffff80002cb6fca0] do_anonymous_page at ffff80000829f5a8
 #8 [ffff80002cb6fce0] __handle_mm_fault at ffff8000082a5974
 #9 [ffff80002cb6fd90] handle_mm_fault at ffff8000082a5bd4

At this point, the pgdat contains the following two zones:

        NODE: 4  ZONE: 0  ADDR: ffff00817fffe540  NAME: "DMA32"
          SIZE: 20480  MIN/LOW/HIGH: 11/28/45
          VM_STAT:
                NR_FREE_PAGES: 359
        NR_ZONE_INACTIVE_ANON: 18813
          NR_ZONE_ACTIVE_ANON: 0
        NR_ZONE_INACTIVE_FILE: 50
          NR_ZONE_ACTIVE_FILE: 0
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

        NODE: 4  ZONE: 1  ADDR: ffff00817fffec00  NAME: "Normal"
          SIZE: 8454144  PRESENT: 98304  MIN/LOW/HIGH: 68/166/264
          VM_STAT:
                NR_FREE_PAGES: 146
        NR_ZONE_INACTIVE_ANON: 94668
          NR_ZONE_ACTIVE_ANON: 3
        NR_ZONE_INACTIVE_FILE: 735
          NR_ZONE_ACTIVE_FILE: 78
          NR_ZONE_UNEVICTABLE: 0
        NR_ZONE_WRITE_PENDING: 0
                     NR_MLOCK: 0
                    NR_BOUNCE: 0
                   NR_ZSPAGES: 0
            NR_FREE_CMA_PAGES: 0

In allow_direct_reclaim(), while processing ZONE_DMA32, the sum of
inactive/active file-backed pages calculated in zone_reclaimable_pages()
based on the result of zone_page_state_snapshot() is zero.

Additionally, since this system lacks swap, the calculation of inactive/
active anonymous pages is skipped.

        crash> p nr_swap_pages
        nr_swap_pages = $1937 = {
          counter = 0
        }

As a result, ZONE_DMA32 is deemed unreclaimable and skipped, moving on to
the processing of the next zone, ZONE_NORMAL, despite ZONE_DMA32 having
free pages significantly exceeding the high watermark.

The problem is that the pgdat->kswapd_failures hasn't been incremented.

        crash> px ((struct pglist_data *) 0xffff00817fffe540)->kswapd_failures
        $1935 = 0x0

This is because the node deemed balanced.  The node balancing logic in
balance_pgdat() evaluates all zones collectively.  If one or more zones
(e.g., ZONE_DMA32) have enough free pages to meet their watermarks, the
entire node is deemed balanced.  This causes balance_pgdat() to exit early
before incrementing the kswapd_failures, as it considers the overall
memory state acceptable, even though some zones (like ZONE_NORMAL) remain
under significant pressure.

The patch ensures that zone_reclaimable_pages() includes free pages
(NR_FREE_PAGES) in its calculation when no other reclaimable pages are
available (e.g., file-backed or anonymous pages).  This change prevents
zones like ZONE_DMA32, which have sufficient free pages, from being
mistakenly deemed unreclaimable.  By doing so, the patch ensures proper
node balancing, avoids masking pressure on other zones like ZONE_NORMAL,
and prevents infinite loops in throttle_direct_reclaim() caused by
allow_direct_reclaim(pgdat) repeatedly returning false.

The kernel hangs due to a task stuck in throttle_direct_reclaim(), caused
by a node being incorrectly deemed balanced despite pressure in certain
zones, such as ZONE_NORMAL.  This issue arises from
zone_reclaimable_pages() returning 0 for zones without reclaimable file-
backed or anonymous pages, causing zones like ZONE_DMA32 with sufficient
free pages to be skipped.

The lack of swap or reclaimable pages results in ZONE_DMA32 being ignored
during reclaim, masking pressure in other zones.  Consequently,
pgdat->kswapd_failures remains 0 in balance_pgdat(), preventing fallback
mechanisms in allow_direct_reclaim() from being triggered, leading to an
infinite loop in throttle_direct_reclaim().

This patch modifies zone_reclaimable_pages() to account for free pages
(NR_FREE_PAGES) when no other reclaimable pages exist.  This ensures zones
with sufficient free pages are not skipped, enabling proper balancing and
reclaim behavior.

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20241130164346.436469-1-snishika@redhat.com
Link: https://lkml.kernel.org/r/20241130161236.433747-2-snishika@redhat.com
Fixes: 5a1c84b ("mm: remove reclaim and compaction retry approximations")
Signed-off-by: Seiji Nishikawa <snishika@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>
Signed-off-by: onettboots <blackcocopet@gmail.com>
onettboots pushed a commit that referenced this pull request Feb 27, 2026
In case of successful page fault handling, this patch releases mmap_sem
before updating the perf stat event for major/minor faults. So even
though the contention reduction is NOT super high, it is still an
improvement.

There's an additional code size improvement as we only have 2 up_read()
calls now.

Note to myself:
--------------

1. Given the way it is done, we are forced to move @bad_area label earlier
   causing the various "goto bad_area" cases to hit perf stat code.

 - PERF_COUNT_SW_PAGE_FAULTS is NOW updated for access errors which is what
   arm/arm64 seem to be doing as well (with slightly different code)
 - PERF_COUNT_SW_PAGE_FAULTS_{MAJ,MIN} must NOT be updated for the
   error case which is guarded by now setting @fault initial value
   to VM_FAULT_ERROR which serves both cases when handle_mm_fault()
   returns error or is not called at all.

2. arm/arm64 use two homebrew fault flags VM_FAULT_BAD{MAP,MAPACCESS}
   which I was inclined to add too but seems not needed for ARC

 - given that we have everything is 1 function we can still use goto
 - we setup si_code at the right place (arm* do that in the end)
 - we init fault already to error value which guards entry into perf
   stats event update

Cc: Peter Zijlstra <peterz@infradead.org>
Change-Id: I35f2d8c2b5f16fdf14213c1167cec61e21938134
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
onettboots pushed a commit that referenced this pull request Feb 28, 2026
In case of successful page fault handling, this patch releases mmap_sem
before updating the perf stat event for major/minor faults. So even
though the contention reduction is NOT super high, it is still an
improvement.

There's an additional code size improvement as we only have 2 up_read()
calls now.

Note to myself:
--------------

1. Given the way it is done, we are forced to move @bad_area label earlier
   causing the various "goto bad_area" cases to hit perf stat code.

 - PERF_COUNT_SW_PAGE_FAULTS is NOW updated for access errors which is what
   arm/arm64 seem to be doing as well (with slightly different code)
 - PERF_COUNT_SW_PAGE_FAULTS_{MAJ,MIN} must NOT be updated for the
   error case which is guarded by now setting @fault initial value
   to VM_FAULT_ERROR which serves both cases when handle_mm_fault()
   returns error or is not called at all.

2. arm/arm64 use two homebrew fault flags VM_FAULT_BAD{MAP,MAPACCESS}
   which I was inclined to add too but seems not needed for ARC

 - given that we have everything is 1 function we can still use goto
 - we setup si_code at the right place (arm* do that in the end)
 - we init fault already to error value which guards entry into perf
   stats event update

Cc: Peter Zijlstra <peterz@infradead.org>
Change-Id: I35f2d8c2b5f16fdf14213c1167cec61e21938134
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
onettboots pushed a commit that referenced this pull request Mar 16, 2026
A recent clang 16 update has introduced segfault when compiling kernel
using the `-polly-invariant-load-hoisting` flag and breaks compilation
when kernel is compiled with full LTO.
This is due to the flag being ignorant about the errors during SCoP
verification and does not take the errors into account as per a recent
issue opened at [LLVM], causing polly to do segfault and the compiler
to print the following backtrace:

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: clang -Wp,-MD,drivers/md/.md.o.d -nostdinc -isystem /tmp/cirrus-ci-build/toolchains/clang/lib/clang/16.0.0/include -I../arch/arm64/include -I./arch/arm64/include/generated -I../include -I./include -I../arch/arm64/include/uapi -I./arch/arm64/include/generated/uapi -I../include/uapi -I./include/generated/uapi -include ../include/linux/kconfig.h -include ../include/linux/compiler_types.h -I../drivers/md -Idrivers/md -D__KERNEL__ -mlittle-endian -DKASAN_SHADOW_SCALE_SHIFT=3 -Qunused-arguments -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -fshort-wchar -Werror-implicit-function-declaration -Werror=return-type -Wno-format-security -std=gnu89 --target=aarch64-linux-gnu --prefix=/tmp/cirrus-ci-build/Kernel/../toolchains/clang/bin/aarch64-linux-gnu- --gcc-toolchain=/tmp/cirrus-ci-build/toolchains/clang -Wno-misleading-indentation -Wno-bool-operation -Werror=unknown-warning-option -Wno-unsequenced -opaque-pointers -fno-PIE -mgeneral-regs-only -DCONFIG_AS_LSE=1 -fno-asynchronous-unwind-tables -Wno-psabi -DKASAN_SHADOW_SCALE_SHIFT=3 -fno-delete-null-pointer-checks -Wno-frame-address -Wno-int-in-bool-context -Wno-address-of-packed-member -O3 -march=armv8.1-a+crypto+fp16+rcpc -mtune=cortex-a53 -mllvm -polly -mllvm -polly-ast-use-context -mllvm -polly-detect-keep-going -mllvm -polly-invariant-load-hoisting -mllvm -polly-run-inliner -mllvm -polly-vectorizer=stripmine -mllvm -polly-loopfusion-greedy=1 -mllvm -polly-reschedule=1 -mllvm -polly-postopts=1 -fstack-protector-strong --target=aarch64-linux-gnu --gcc-toolchain=/tmp/cirrus-ci-build/toolchains/clang -meabi gnu -Wno-format-invalid-specifier -Wno-gnu -Wno-duplicate-decl-specifier -Wno-asm-operand-widths -Wno-initializer-overrides -Wno-tautological-constant-out-of-range-compare -Wno-tautological-compare -mno-global-merge -Wno-void-ptr-dereference -Wno-unused-but-set-variable -Wno-unused-const-variable -fno-omit-frame-pointer -fno-optimize-sibling-calls -Wvla -flto -fwhole-program-vtables -fvisibility=hidden -Wdeclaration-after-statement -Wno-pointer-sign -Wno-array-bounds -fno-strict-overflow -fno-stack-check -Werror=implicit-int -Werror=strict-prototypes -Werror=date-time -Werror=incompatible-pointer-types -fmacro-prefix-map=../= -Wno-initializer-overrides -Wno-unused-value -Wno-format -Wno-sign-compare -Wno-format-zero-length -Wno-uninitialized -Wno-pointer-to-enum-cast -Wno-unaligned-access -DKBUILD_BASENAME=\"md\" -DKBUILD_MODNAME=\"md_mod\" -D__KBUILD_MODNAME=kmod_md_mod -c -o drivers/md/md.o ../drivers/md/md.c
1.	<eof> parser at end of file
2.	Optimizer
  CC      drivers/media/platform/msm/camera_v2/camera/camera.o
  AR      drivers/media/pci/intel/ipu3/built-in.a
  CC      drivers/md/dm-linear.o
 #0 0x0000559d3527073f (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x3a7073f)
 #1 0x0000559d352705bf (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x3a705bf)
 #2 0x0000559d3523b198 (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x3a3b198)
 #3 0x0000559d3523b33e (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x3a3b33e)
 #4 0x00007f339dc3ea00 (/usr/lib/libc.so.6+0x38a00)
 #5 0x0000559d35affccf (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x42ffccf)
 #6 0x0000559d35b01710 (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x4301710)
 #7 0x0000559d35b01a12 (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x4301a12)
 #8 0x0000559d35b09a9e (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x4309a9e)
 #9 0x0000559d35b14707 (/tmp/cirrus-ci-build/toolchains/clang/bin/clang-16+0x4314707)
clang-16: error: clang frontend command failed with exit code 139 (use -v to see invocation)
Neutron clang version 16.0.0 (https://github.com/llvm/llvm-project.git 598f5275c16049b1e1b5bc934cbde447a82d485e)
Target: aarch64-unknown-linux-gnu
Thread model: posix
InstalledDir: /tmp/cirrus-ci-build/Kernel/../toolchains/clang/bin

From the very nature of `-polly-detect-keep-going`, it can be concluded
that this is a potentially unsafe flag and instead of using it conditionally
for CLANG < 16, just remove it all together for all. This should allow polly
to run SCoP verifications as intended.

Issue [LLVM]: llvm/llvm-project#58484 (comment)

Signed-off-by: Tashfin Shakeer Rhythm <tashfinshakeerrhythm@gmail.com>
Signed-off-by: Cyber Knight <cyberknight755@gmail.com>
Signed-off-by: onettboots <blackcocopet@gmail.com>
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