From b96672dd840f2231c3e0804842d380c401739733 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Wed, 19 Jul 2017 16:59:12 +1000 Subject: [PATCH] powerpc: Machine check interrupt is a non-maskable interrupt Use nmi_enter similarly to system reset interrupts. This uses NMI printk NMI buffers and turns off various debugging facilities that helps avoid tripping on ourselves or other CPUs. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/traps.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 6858d91..ec74e20 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -644,8 +644,10 @@ int machine_check_generic(struct pt_regs *regs) void machine_check_exception(struct pt_regs *regs) { - enum ctx_state prev_state = exception_enter(); int recover = 0; + bool nested = in_nmi(); + if (!nested) + nmi_enter(); /* 64s accounts the mce in machine_check_early when in HVMODE */ if (!IS_ENABLED(CONFIG_PPC_BOOK3S_64) || !cpu_has_feature(CPU_FTR_HVMODE)) @@ -677,10 +679,11 @@ void machine_check_exception(struct pt_regs *regs) /* Must die if the interrupt is not recoverable */ if (!(regs->msr & MSR_RI)) - panic("Unrecoverable Machine check"); + nmi_panic(regs, "Unrecoverable Machine check"); bail: - exception_exit(prev_state); + if (!nested) + nmi_exit(); } void SMIException(struct pt_regs *regs) -- 2.7.4