[tip: x86/core] x86/stackprotector: Move __stack_chk_guard to percpu hot section

From: tip-bot2 for Brian Gerst
Date: Tue Mar 04 2025 - 03:27:56 EST


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

Commit-ID: 0d3cd124b77ab546ba4284587fb6a72322a89daf
Gitweb: https://git.kernel.org/tip/0d3cd124b77ab546ba4284587fb6a72322a89daf
Author: Brian Gerst <brgerst@xxxxxxxxx>
AuthorDate: Mon, 03 Mar 2025 11:52:45 -05:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Mon, 03 Mar 2025 21:37:41 +01:00

x86/stackprotector: Move __stack_chk_guard to percpu hot section

No functional change.

Signed-off-by: Brian Gerst <brgerst@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Acked-by: Uros Bizjak <ubizjak@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20250303165246.2175811-11-brgerst@xxxxxxxxx
---
arch/x86/include/asm/stackprotector.h | 2 +-
arch/x86/kernel/cpu/common.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h
index d43fb58..cd761b1 100644
--- a/arch/x86/include/asm/stackprotector.h
+++ b/arch/x86/include/asm/stackprotector.h
@@ -20,7 +20,7 @@

#include <linux/sched.h>

-DECLARE_PER_CPU(unsigned long, __stack_chk_guard);
+DECLARE_PER_CPU_CACHE_HOT(unsigned long, __stack_chk_guard);

/*
* Initialize the stackprotector canary value.
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 39782a2..a1c0efc 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -2130,7 +2130,7 @@ void syscall_init(void)
#endif /* CONFIG_X86_64 */

#ifdef CONFIG_STACKPROTECTOR
-DEFINE_PER_CPU(unsigned long, __stack_chk_guard);
+DEFINE_PER_CPU_CACHE_HOT(unsigned long, __stack_chk_guard);
#ifndef CONFIG_SMP
EXPORT_PER_CPU_SYMBOL(__stack_chk_guard);
#endif