From 03871da61a22727704651ee442d650be87913e79 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 29 Sep 2017 13:29:37 +1000 Subject: [PATCH] powerpc/watchdog: Do not panic from locked CPU's IPI handler The SMP watchdog will detect locked CPUs and IPI them to print a backtrace and registers. If panic on hard lockup is enabled, do not panic from this handler, because that can cause recursion into the IPI layer during the panic. The caller already panics in this case. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/watchdog.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/watchdog.c b/arch/powerpc/kernel/watchdog.c index 2f6eadd9408d9..532a1adbe89bb 100644 --- a/arch/powerpc/kernel/watchdog.c +++ b/arch/powerpc/kernel/watchdog.c @@ -97,8 +97,7 @@ static void wd_lockup_ipi(struct pt_regs *regs) else dump_stack(); - if (hardlockup_panic) - nmi_panic(regs, "Hard LOCKUP"); + /* Do not panic from here because that can recurse into NMI IPI layer */ } static void set_cpumask_stuck(const struct cpumask *cpumask, u64 tb) -- 2.39.5