[tip: x86/entry] x86/speculation/mds: Mark mds_user_clear_cpu_buffers() __always_inline

[tip-bot2 for Thomas Gleixner]

The following commit has been merged into the x86/entry branch of tip:

Commit-ID:     c48dd99ee6c2fe0a5a3e1667eca0cceb57797d21
Gitweb:        https://git.kernel.org/tip/c48dd99ee6c2fe0a5a3e1667eca0cceb57797d21
Author:        Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate:    Wed, 04 Mar 2020 12:49:18 +01:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Tue, 19 May 2020 16:03:51 +02:00

x86/speculation/mds: Mark mds_user_clear_cpu_buffers() __always_inline

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


---
 arch/x86/include/asm/nospec-branch.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index d52d1aa..e7752b4 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -262,7 +262,7 @@ 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;
 
@@ -283,7 +283,7 @@ 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();