Commit a99b9c5e authored Aug 01, 2018 by Murilo Opsfelder Araujo Committed by Michael Ellerman Aug 08, 2018

powerpc/traps: Show instructions on exceptions

Call show_user_instructions() in arch/powerpc/kernel/traps.c to dump
instructions at faulty location, useful to debugging.

Before this patch, an unhandled signal message looked like:

pandafault[10524]: segfault (11) at 100007d0 nip 1000061c lr 7fffbd295100 code 2 in pandafault[10000000+10000]

After this patch, it looks like:

pandafault[10524]: segfault (11) at 100007d0 nip 1000061c lr 7fffbd295100 code 2 in pandafault[10000000+10000]
pandafault[10524]: code: 4bfffeec 4bfffee8 3c401002 38427f00 fbe1fff8 f821ffc1 7c3f0b78 3d22fffe
pandafault[10524]: code: 392988d0 f93f0020 e93f0020 39400048 <99490000> 39200000 7d234b78 383f0040

Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent 88b0fe17

arch/powerpc/kernel/traps.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,7 @@
		#include <asm/hmi.h>
		#include <sysdev/fsl_pci.h>
		#include <asm/kprobes.h>
		#include <asm/stacktrace.h>

		#if defined(CONFIG_DEBUGGER) \|\| defined(CONFIG_KEXEC_CORE)
		int (__debugger)(struct pt_regs regs) __read_mostly;
		@@ -337,6 +338,8 @@ static void show_signal_msg(int signr, struct pt_regs *regs, int code,
		print_vma_addr(KERN_CONT " in ", regs->nip);

		pr_cont("\n");

		show_user_instructions(regs);
		}

		void _exception_pkey(int signr, struct pt_regs *regs, int code,