From: Uros Bizjak <ubizjak@gmail.com>
Date: Mon, 3 Mar 2025 15:54:24 +0000 (+0100)
Subject: x86/irq/32: Use current_stack_pointer to avoid asm() in check_stack_overflow()
X-Git-Tag: v6.15-rc1~216^2~86^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d4432fb5b8798a7663974bed277a8a6e330a50d8;p=thirdparty%2Fkernel%2Flinux.git

x86/irq/32: Use current_stack_pointer to avoid asm() in check_stack_overflow()

Make code more readable by using the 'current_stack_pointer' global variable.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250303155446.112769-4-ubizjak@gmail.com
---

diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index eab458009f973..8c7babbcf6b70 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -31,10 +31,7 @@ int sysctl_panic_on_stackoverflow __read_mostly;
 /* Debugging check for stack overflow: is there less than 1KB free? */
 static int check_stack_overflow(void)
 {
-	long sp;
-
-	__asm__ __volatile__("andl %%esp,%0" :
-			     "=r" (sp) : "0" (THREAD_SIZE - 1));
+	unsigned long sp = current_stack_pointer & (THREAD_SIZE - 1);
 
 	return sp < (sizeof(struct thread_info) + STACK_WARN);
 }