This is a note to let you know that I've just added the patch titled
tick/common: Touch watchdog in tick_unfreeze() on all CPUs
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tick-common-touch-watchdog-in-tick_unfreeze-on-all-cpus.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 5167c506d62dd9ffab73eba23c79b0a8845c9fe1 Mon Sep 17 00:00:00 2001
From: Chunyan Zhang <zhang.lyra@xxxxxxxxx>
Date: Fri, 10 Jan 2020 16:39:02 +0800
Subject: tick/common: Touch watchdog in tick_unfreeze() on all CPUs
From: Chunyan Zhang <zhang.lyra@xxxxxxxxx>
commit 5167c506d62dd9ffab73eba23c79b0a8845c9fe1 upstream.
Suspend to IDLE invokes tick_unfreeze() on resume. tick_unfreeze() on the
first resuming CPU resumes timekeeping, which also has the side effect of
resetting the softlockup watchdog on this CPU.
But on the secondary CPUs the watchdog is not reset in the resume /
unfreeze() path, which can result in false softlockup warnings on those
CPUs depending on the time spent in suspend.
Prevent this by clearing the softlock watchdog in the unfreeze path also
on the secondary resuming CPUs.
[ tglx: Massaged changelog ]
Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200110083902.27276-1-chunyan.zhang@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/time/tick-common.c | 2 ++
1 file changed, 2 insertions(+)
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -11,6 +11,7 @@
#include <linux/err.h>
#include <linux/hrtimer.h>
#include <linux/interrupt.h>
+#include <linux/nmi.h>
#include <linux/percpu.h>
#include <linux/profile.h>
#include <linux/sched.h>
@@ -558,6 +559,7 @@ void tick_unfreeze(void)
trace_suspend_resume(TPS("timekeeping_freeze"),
smp_processor_id(), false);
} else {
+ touch_softlockup_watchdog();
tick_resume_local();
}
Patches currently in stable-queue which might be from zhang.lyra@xxxxxxxxx are
queue-5.4/mfd-sprd-add-wakeup-capability-for-pmic-irq.patch
queue-5.4/tick-common-touch-watchdog-in-tick_unfreeze-on-all-cpus.patch
