From eb6f2d4be0ecb2f1091e1b6c9fda8f42e10a2328 Mon Sep 17 00:00:00 2001
From: Jethro Beekman <jethro@fortanix.com>
Date: Tue, 27 Jul 2021 12:10:24 +0200
Subject: [PATCH 1/2] Revert "SGX mutex is movable"
This reverts commit 30b82e0f96579d9f897c4e2a780af82662d89772.
---
library/std/src/sys/sgx/mutex.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/library/std/src/sys/sgx/mutex.rs b/library/std/src/sys/sgx/mutex.rs
index 1b5ced4178f6a..8874517dac60c 100644
--- a/library/std/src/sys/sgx/mutex.rs
+++ b/library/std/src/sys/sgx/mutex.rs
@@ -8,7 +8,7 @@ pub struct Mutex {
inner: SpinMutex<WaitVariable<bool>>,
}
-pub type MovableMutex = Mutex;
+pub type MovableMutex = Box<Mutex>;
// Implementation according to “Operating Systems: Three Easy Pieces”, chapter 28
impl Mutex {
From b518dc7a316b172f474be97e2139cb36b1b15f2f Mon Sep 17 00:00:00 2001
From: Jethro Beekman <jethro@fortanix.com>
Date: Tue, 27 Jul 2021 12:11:20 +0200
Subject: [PATCH 2/2] Add warning to SGX mutex implementation
---
library/std/src/sys/sgx/mutex.rs | 1 +
library/std/src/sys/sgx/waitqueue/unsafe_list.rs | 1 +
2 files changed, 2 insertions(+)
diff --git a/library/std/src/sys/sgx/mutex.rs b/library/std/src/sys/sgx/mutex.rs
index 8874517dac60c..0b2d1f4487f61 100644
--- a/library/std/src/sys/sgx/mutex.rs
+++ b/library/std/src/sys/sgx/mutex.rs
@@ -8,6 +8,7 @@ pub struct Mutex {
inner: SpinMutex<WaitVariable<bool>>,
}
+// not movable: see UnsafeList implementation
pub type MovableMutex = Box<Mutex>;
// Implementation according to “Operating Systems: Three Easy Pieces”, chapter 28
diff --git a/library/std/src/sys/sgx/waitqueue/unsafe_list.rs b/library/std/src/sys/sgx/waitqueue/unsafe_list.rs
index cf2f0886c1546..c736cab576e4d 100644
--- a/library/std/src/sys/sgx/waitqueue/unsafe_list.rs
+++ b/library/std/src/sys/sgx/waitqueue/unsafe_list.rs
@@ -23,6 +23,7 @@ impl<T> UnsafeListEntry<T> {
}
}
+// WARNING: self-referential struct!
pub struct UnsafeList<T> {
head_tail: NonNull<UnsafeListEntry<T>>,
head_tail_entry: Option<UnsafeListEntry<T>>,