This is a note to let you know that I've just added the patch titled
PM: sleep: core: Avoid setting power.must_resume to false
to the 5.10-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:
pm-sleep-core-avoid-setting-power.must_resume-to-false.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4a9344cd0aa4499beb3772bbecb40bb78888c0e1 Mon Sep 17 00:00:00 2001
From: Prasad Sodagudi <psodagud@xxxxxxxxxxxxxx>
Date: Tue, 7 Sep 2021 04:24:23 -0700
Subject: PM: sleep: core: Avoid setting power.must_resume to false
From: Prasad Sodagudi <psodagud@xxxxxxxxxxxxxx>
commit 4a9344cd0aa4499beb3772bbecb40bb78888c0e1 upstream.
There are variables(power.may_skip_resume and dev->power.must_resume)
and DPM_FLAG_MAY_SKIP_RESUME flags to control the resume of devices after
a system wide suspend transition.
Setting the DPM_FLAG_MAY_SKIP_RESUME flag means that the driver allows
its "noirq" and "early" resume callbacks to be skipped if the device
can be left in suspend after a system-wide transition into the working
state. PM core determines that the driver's "noirq" and "early" resume
callbacks should be skipped or not with dev_pm_skip_resume() function by
checking power.may_skip_resume variable.
power.must_resume variable is getting set to false in __device_suspend()
function without checking device's DPM_FLAG_MAY_SKIP_RESUME settings.
In problematic scenario, where all the devices in the suspend_late
stage are successful and some device can fail to suspend in
suspend_noirq phase. So some devices successfully suspended in suspend_late
stage are not getting chance to execute __device_suspend_noirq()
to set dev->power.must_resume variable to true and not getting
resumed in early_resume phase.
Add a check for device's DPM_FLAG_MAY_SKIP_RESUME flag before
setting power.must_resume variable in __device_suspend function.
Fixes: 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase")
Signed-off-by: Prasad Sodagudi <psodagud@xxxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/base/power/main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -1644,7 +1644,7 @@ static int __device_suspend(struct devic
}
dev->power.may_skip_resume = true;
- dev->power.must_resume = false;
+ dev->power.must_resume = !dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME);
dpm_watchdog_set(&wd, dev);
device_lock(dev);
Patches currently in stable-queue which might be from psodagud@xxxxxxxxxxxxxx are
queue-5.10/pm-sleep-core-avoid-setting-power.must_resume-to-false.patch
