From d1705c558c95418378b11a0be963fe1b3e2fa381 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 12 Oct 2009 11:32:31 -0700 Subject: [PATCH] x86: fix kernel panic on 32 bits when profiling Latest kernel has a kernel panic in booting on i386 machine when profile=2 setting in cmdline. It is due to 'sp' being incorrect in profile_pc(). BUG: unable to handle kernel NULL pointer dereference at 00000246 IP: [] profile_pc+0x2a/0x48 *pde = 00000000 Oops: 0000 [#1] SMP This differs from the original version by Alex Shi in that we use the kernel_stack_pointer() inline already defined in for this purpose, instead of #ifdef. Originally-by: Alex Shi Cc: "Chen, Tim C" Cc: "Rafael J. Wysocki" Cc: Andrew Morton Signed-off-by: H. Peter Anvin --- arch/x86/kernel/time.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c index dcb00d27851..be2573448ed 100644 --- a/arch/x86/kernel/time.c +++ b/arch/x86/kernel/time.c @@ -38,7 +38,8 @@ unsigned long profile_pc(struct pt_regs *regs) #ifdef CONFIG_FRAME_POINTER return *(unsigned long *)(regs->bp + sizeof(long)); #else - unsigned long *sp = (unsigned long *)regs->sp; + unsigned long *sp = + (unsigned long *)kernel_stack_pointer(regs); /* * Return address is either directly at stack pointer * or above a saved flags. Eflags has bits 22-31 zero, -- 2.39.3