[tip: x86/urgent] Revert "x86/bugs: Use fixed addressing for VERW operand"

From: tip-bot2 for Dave Hansen
Date: Wed Mar 13 2024 - 05:17:33 EST


The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: bfa5fa246c0724c2cc1bd0dfe57531aaa7f520c1
Gitweb: https://git.kernel.org/tip/bfa5fa246c0724c2cc1bd0dfe57531aaa7f520c1
Author: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
AuthorDate: Tue, 12 Mar 2024 07:27:57 -07:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Wed, 13 Mar 2024 10:08:09 +01:00

Revert "x86/bugs: Use fixed addressing for VERW operand"

This was reverts commit 8009479ee919b9a91674f48050ccbff64eafedaa.

It was originally in x86/urgent, but was deemed wrong so got zapped.
But in the meantime, x86/urgent had been merged into x86/apic to
resolve a conflict. I didn't notice the merge so didn't zap it
from x86/apic and it managed to make it up with the x86/apic
material.

The reverted commit is known to cause some KASAN problems.

Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/nospec-branch.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index d0b8bb7..fc3a8a3 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -314,7 +314,7 @@
* Note: Only the memory operand variant of VERW clears the CPU buffers.
*/
.macro CLEAR_CPU_BUFFERS
- ALTERNATIVE "", __stringify(verw mds_verw_sel), X86_FEATURE_CLEAR_CPU_BUF
+ ALTERNATIVE "", __stringify(verw _ASM_RIP(mds_verw_sel)), X86_FEATURE_CLEAR_CPU_BUF
.endm

#else /* __ASSEMBLY__ */