From: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Date: Wed, 10 Mar 2021 14:23:37 +0100
Subject: [PATCH] s390/vtime: fix increased steal time accounting
Patch-mainline: v5.12-rc4
Git-commit: d54cb7d54877d529bc1e0e1f47a3dd082f73add3
References: bsc#1183861

Commit 152e9b8676c6e ("s390/vtime: steal time exponential moving average")
inadvertently changed the input value for account_steal_time() from
"cputime_to_nsecs(steal)" to just "steal", resulting in broken increased
steal time accounting.

Fix this by changing it back to "cputime_to_nsecs(steal)".

Fixes: 152e9b8676c6e ("s390/vtime: steal time exponential moving average")
Cc: <stable@vger.kernel.org> # 5.1
Reported-by: Sabine Forkel <sabine.forkel@de.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Cho, Yu-Chen <acho@suse.com>
---
 arch/s390/kernel/vtime.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/s390/kernel/vtime.c
+++ b/arch/s390/kernel/vtime.c
@@ -219,7 +219,7 @@ void vtime_flush(struct task_struct *tsk
 	avg_steal = S390_lowcore.avg_steal_timer / 2;
 	if ((s64) steal > 0) {
 		S390_lowcore.steal_timer = 0;
-		account_steal_time(steal);
+		account_steal_time(cputime_to_nsecs(steal));
 		avg_steal += steal;
 	}
 	S390_lowcore.avg_steal_timer = avg_steal;