From 81c2949f7fdcf8ff681326669afde24962232670 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Tue, 5 Jul 2016 00:31:27 +0200 Subject: x86/dumpstack: Add show_stack_regs() and use it Add a helper to dump supplied pt_regs and use it in the MSR exception handling code to have precise stack traces pointing to the actual function causing the MSR access exception and not the stack frame of the exception handler itself. The new output looks like this: unchecked MSR access error: RDMSR from 0xdeadbeef at rIP: 0xffffffff8102ddb6 (early_init_intel+0x16/0x3a0) 00000000756e6547 ffffffff81c03f68 ffffffff81dd0940 ffffffff81c03f10 ffffffff81d42e65 0000000001000000 ffffffff81c03f58 ffffffff81d3e5a3 0000800000000000 ffffffff81800080 ffffffffffffffff 0000000000000000 Call Trace: [] early_cpu_init+0xe7/0x136 [] setup_arch+0xa5/0x9df [] start_kernel+0x9f/0x43a [] x86_64_start_reservations+0x2f/0x31 [] x86_64_start_kernel+0x168/0x176 Signed-off-by: Borislav Petkov Reviewed-by: Andy Lutomirski Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1467671487-10344-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar --- arch/x86/include/asm/kdebug.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/include/asm/kdebug.h') diff --git a/arch/x86/include/asm/kdebug.h b/arch/x86/include/asm/kdebug.h index e5f5dc9787d5..1ef9d581b5d9 100644 --- a/arch/x86/include/asm/kdebug.h +++ b/arch/x86/include/asm/kdebug.h @@ -26,6 +26,7 @@ extern void die(const char *, struct pt_regs *,long); extern int __must_check __die(const char *, struct pt_regs *, long); extern void show_trace(struct task_struct *t, struct pt_regs *regs, unsigned long *sp, unsigned long bp); +extern void show_stack_regs(struct pt_regs *regs); extern void __show_regs(struct pt_regs *regs, int all); extern unsigned long oops_begin(void); extern void oops_end(unsigned long, struct pt_regs *, int signr); -- cgit v1.2.3