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Subject[PATCH] x86/retpoline: Remove the esp/rsp thunk
Date
It doesn't make sense to have an indirect call thunk with esp/rsp as
retpoline code won't work correctly with the stack pointer register.
Removing it will help compiler writers to catch error in case such
a thunk call is emitted incorrectly.

Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support")
Suggested-by: Jeff Law <law@redhat.com>
Signed-off-by: Waiman Long <longman@redhat.com>
---
arch/x86/include/asm/asm-prototypes.h | 1 -
arch/x86/lib/retpoline.S | 1 -
2 files changed, 2 deletions(-)

diff --git a/arch/x86/include/asm/asm-prototypes.h b/arch/x86/include/asm/asm-prototypes.h
index 0927cdc..1908214 100644
--- a/arch/x86/include/asm/asm-prototypes.h
+++ b/arch/x86/include/asm/asm-prototypes.h
@@ -38,5 +38,4 @@
INDIRECT_THUNK(si)
INDIRECT_THUNK(di)
INDIRECT_THUNK(bp)
-INDIRECT_THUNK(sp)
#endif /* CONFIG_RETPOLINE */
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index dfb2ba9..c909961 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -36,7 +36,6 @@ GENERATE_THUNK(_ASM_DX)
GENERATE_THUNK(_ASM_SI)
GENERATE_THUNK(_ASM_DI)
GENERATE_THUNK(_ASM_BP)
-GENERATE_THUNK(_ASM_SP)
#ifdef CONFIG_64BIT
GENERATE_THUNK(r8)
GENERATE_THUNK(r9)
--
1.8.3.1
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