From b96672dd840f2231c3e0804842d380c401739733 Mon Sep 17 00:00:00 2001
From: Nicholas Piggin <npiggin@gmail.com>
Date: Wed, 19 Jul 2017 16:59:12 +1000
Subject: [PATCH] powerpc: Machine check interrupt is a non-maskable interrupt
References: bsc#1094244
Patch-mainline: v4.14-rc1
Git-commit: b96672dd840f2231c3e0804842d380c401739733
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 <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
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 6858d910b47e..ec74e203ee04 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)
--
2.13.7