This is a note to let you know that I've just added the patch titled
x86/speculation/mds: Mark mds_user_clear_cpu_buffers() __always_inline
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-speculation-mds-mark-mds_user_clear_cpu_buffers-.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 434ace27808e8505c62f41ec1ce6a1a1b1594b75
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Date: Wed Mar 4 12:49:18 2020 +0100
x86/speculation/mds: Mark mds_user_clear_cpu_buffers() __always_inline
[ Upstream commit a7ef9ba986b5fae9d80f8a7b31db0423687efe4e ]
Prevent the compiler from uninlining and creating traceable/probable
functions as this is invoked _after_ context tracking switched to
CONTEXT_USER and rcu idle.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Alexandre Chartre <alexandre.chartre@xxxxxxxxxx>
Acked-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20200505134340.902709267@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 5c24a7b351665..b222a35959467 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -320,7 +320,7 @@ DECLARE_STATIC_KEY_FALSE(mds_idle_clear);
* combination with microcode which triggers a CPU buffer flush when the
* instruction is executed.
*/
-static inline void mds_clear_cpu_buffers(void)
+static __always_inline void mds_clear_cpu_buffers(void)
{
static const u16 ds = __KERNEL_DS;
@@ -341,7 +341,7 @@ static inline void mds_clear_cpu_buffers(void)
*
* Clear CPU buffers if the corresponding static key is enabled
*/
-static inline void mds_user_clear_cpu_buffers(void)
+static __always_inline void mds_user_clear_cpu_buffers(void)
{
if (static_branch_likely(&mds_user_clear))
mds_clear_cpu_buffers();
