From a4653228a0f8d0a4a76d03a2dd15beaf6e78c22b Mon Sep 17 00:00:00 2001 From: Dave P Martin Date: Fri, 24 Jul 2015 16:37:49 +0100 Subject: [PATCH] arm64/BUG: Show explicit backtrace for WARNs The generic slowpath WARN implementation prints a backtrace, but the report_bug() based implementation does not, opting to print the registers instead which is generally not as useful. Ideally, report_bug() should be fixed to make the behaviour more consistent, but in the meantime this patch generates a backtrace directly from the arm64 backend instead so that this functionality is not lost with the migration to report_bug(). As a side-effect, the backtrace will be outside the oops end marker, but that's hard to avoid without modifying generic code. This patch can go away if report_bug() grows the ability in the future to generate a backtrace directly or call an arch hook at the appropriate time. Signed-off-by: Dave Martin Acked-by: Catalin Marinas Signed-off-by: Will Deacon --- arch/arm64/kernel/traps.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 824ba5ac6361..f93aae5e4307 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -494,6 +494,8 @@ static int bug_handler(struct pt_regs *regs, unsigned int esr) break; case BUG_TRAP_TYPE_WARN: + /* Ideally, report_bug() should backtrace for us... but no. */ + dump_backtrace(regs, NULL); break; default: -- 2.39.5