diff options
| author | Josh Poimboeuf <[email protected]> | 2025-04-08 21:47:31 +0000 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2025-04-09 10:41:30 +0000 |
| commit | fc9fd3f98423367c79e0bd85a9515df26dc1b3cc (patch) | |
| tree | 86cbab691334e23f96e98bd6999a76bfd61aba76 | |
| parent | x86/bugs: Rename entry_ibpb() to write_ibpb() (diff) | |
| download | kernel-fc9fd3f98423367c79e0bd85a9515df26dc1b3cc.tar.gz kernel-fc9fd3f98423367c79e0bd85a9515df26dc1b3cc.zip | |
x86/bugs: Use SBPB in write_ibpb() if applicable
write_ibpb() does IBPB, which (among other things) flushes branch type
predictions on AMD. If the CPU has SRSO_NO, or if the SRSO mitigation
has been disabled, branch type flushing isn't needed, in which case the
lighter-weight SBPB can be used.
The 'x86_pred_cmd' variable already keeps track of whether IBPB or SBPB
should be used. Use that instead of hardcoding IBPB.
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/17c5dcd14b29199b75199d67ff7758de9d9a4928.1744148254.git.jpoimboe@kernel.org
| -rw-r--r-- | arch/x86/entry/entry.S | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/entry/entry.S b/arch/x86/entry/entry.S index cabe65ac8379..175958b02f2b 100644 --- a/arch/x86/entry/entry.S +++ b/arch/x86/entry/entry.S @@ -21,7 +21,7 @@ SYM_FUNC_START(write_ibpb) ANNOTATE_NOENDBR movl $MSR_IA32_PRED_CMD, %ecx - movl $PRED_CMD_IBPB, %eax + movl _ASM_RIP(x86_pred_cmd), %eax xorl %edx, %edx wrmsr |