[PATCH 19/22] x86/srso: Improve i-cache locality for alias mitigation

From: Josh Poimboeuf
Date: Sun Aug 20 2023 - 21:20:06 EST


Move srso_alias_return_thunk() to the same section as
srso_alias_safe_ret() so they can share a cache line.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
arch/x86/lib/retpoline.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index af3c1f0e4fb8..415521dbe15e 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -166,14 +166,14 @@ SYM_CODE_START_NOALIGN(srso_alias_safe_ret)
ret
int3
SYM_FUNC_END(srso_alias_safe_ret)
- .popsection

-SYM_CODE_START(srso_alias_return_thunk)
+SYM_CODE_START_NOALIGN(srso_alias_return_thunk)
UNWIND_HINT_FUNC
ANNOTATE_NOENDBR
call srso_alias_safe_ret
ud2
SYM_CODE_END(srso_alias_return_thunk)
+ .popsection

/*
* SRSO untraining sequence for Zen1/2, similar to retbleed_untrain_ret()
--
2.41.0