From: Thomas Gleixner <tglx@linutronix.de>

Date: Wed, 4 Mar 2020 12:49:18 +0100

Subject: x86/speculation/mds: Mark mds_user_clear_cpu_buffers()

 __always_inline

Git-commit: a7ef9ba986b5fae9d80f8a7b31db0423687efe4e

Patch-mainline: 5.8-rc1

References: git-fixes

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@linutronix.de>

Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>

Acked-by: Peter Zijlstra <peterz@infradead.org>

Link: https://lkml.kernel.org/r/20200505134340.902709267@linutronix.de

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 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 d52d1aac..e7752b40 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();

-- 

2.35.3