From: Nicholas Piggin <npiggin@gmail.com>
Date: Sat, 30 Jan 2021 13:08:35 +0000 (+1000)
Subject: powerpc: improve handling of unrecoverable system reset
X-Git-Tag: v4.19.181~73
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b960e8dc768be3a0de10a0f17a7e4d60b7a5460c;p=thirdparty%2Fkernel%2Fstable.git

powerpc: improve handling of unrecoverable system reset

[ Upstream commit 11cb0a25f71818ca7ab4856548ecfd83c169aa4d ]

If an unrecoverable system reset hits in process context, the system
does not have to panic. Similar to machine check, call nmi_exit()
before die().

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210130130852.2952424-26-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 1b2d84cb373bb..2379c4bf3979e 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -433,8 +433,11 @@ out:
 		die("Unrecoverable nested System Reset", regs, SIGABRT);
 #endif
 	/* Must die if the interrupt is not recoverable */
-	if (!(regs->msr & MSR_RI))
+	if (!(regs->msr & MSR_RI)) {
+		/* For the reason explained in die_mce, nmi_exit before die */
+		nmi_exit();
 		die("Unrecoverable System Reset", regs, SIGABRT);
+	}
 
 	if (!nested)
 		nmi_exit();