[PATCH AUTOSEL 4.14 102/127] powerpc/traps: Make unrecoverable NMIs die instead of panic

From: Sasha Levin
Date: Thu Sep 17 2020 - 22:31:29 EST


From: Nicholas Piggin <npiggin@xxxxxxxxx>

[ Upstream commit 265d6e588d87194c2fe2d6c240247f0264e0c19b ]

System Reset and Machine Check interrupts that are not recoverable due
to being nested or interrupting when RI=0 currently panic. This is not
necessary, and can often just kill the current context and recover.

Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxx>
Link: https://lore.kernel.org/r/20200508043408.886394-16-npiggin@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/kernel/traps.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 3c9457420aee8..0f1a888c04a84 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -357,11 +357,11 @@ out:
#ifdef CONFIG_PPC_BOOK3S_64
BUG_ON(get_paca()->in_nmi == 0);
if (get_paca()->in_nmi > 1)
- nmi_panic(regs, "Unrecoverable nested System Reset");
+ die("Unrecoverable nested System Reset", regs, SIGABRT);
#endif
/* Must die if the interrupt is not recoverable */
if (!(regs->msr & MSR_RI))
- nmi_panic(regs, "Unrecoverable System Reset");
+ die("Unrecoverable System Reset", regs, SIGABRT);

if (!nested)
nmi_exit();
@@ -701,7 +701,7 @@ void machine_check_exception(struct pt_regs *regs)

/* Must die if the interrupt is not recoverable */
if (!(regs->msr & MSR_RI))
- nmi_panic(regs, "Unrecoverable Machine check");
+ die("Unrecoverable Machine check", regs, SIGBUS);

return;

--
2.25.1