Commit 590bcc21 authored Mar 04, 2020 by Thomas Gleixner Committed by Greg Kroah-Hartman Oct 01, 2020

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@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: Sasha Levin <sashal@kernel.org>

parent 95d6ed69

arch/x86/include/asm/nospec-branch.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -321,7 +321,7 @@ 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;

		@@ -342,7 +342,7 @@ 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();