The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 1874cb13d5d7cafa61ce93a760093ebc5485b6ab Mon Sep 17 00:00:00 2001
From: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Date: Mon, 17 May 2021 08:18:12 +0200
Subject: [PATCH] s390/mcck: fix invalid KVM guest condition check
Wrong condition check is used to decide if a machine check hit
while in KVM guest. As result of this check the instruction
following the SIE critical section might be considered as still
in KVM guest and _CIF_MCCK_GUEST CPU flag mistakenly set as
result.
Fixes: c929500d7a5a ("s390/nmi: s390: New low level handling for machine check happening in guest")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 3a81e38c95e7..9cc71ca9a88f 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -653,7 +653,7 @@ ENDPROC(stack_overflow)
slgr %r9,%r13
lghi %r13,.Lsie_skip - .Lsie_entry
clgr %r9,%r13
- jh .Lcleanup_sie_int
+ jhe .Lcleanup_sie_int
oi __LC_CPU_FLAGS+7, _CIF_MCCK_GUEST
.Lcleanup_sie_int:
BPENTER __SF_SIE_FLAGS(%r15),(_TIF_ISOLATE_BP|_TIF_ISOLATE_BP_GUEST)
