This is a note to let you know that I've just added the patch titled
PM: hibernate: Freeze kernel threads in software_resume()
to the 5.6-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-hibernate-freeze-kernel-threads-in-software_resum.patch
and it can be found in the queue-5.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1471f6ab6211afc62512151a8965fb6787421b37
Author: Dexuan Cui <decui@xxxxxxxxxxxxx>
Date: Thu Apr 23 20:40:16 2020 -0700
PM: hibernate: Freeze kernel threads in software_resume()
commit 2351f8d295ed63393190e39c2f7c1fee1a80578f upstream.
Currently the kernel threads are not frozen in software_resume(), so
between dpm_suspend_start(PMSG_QUIESCE) and resume_target_kernel(),
system_freezable_power_efficient_wq can still try to submit SCSI
commands and this can cause a panic since the low level SCSI driver
(e.g. hv_storvsc) has quiesced the SCSI adapter and can not accept
any SCSI commands: https://lkml.org/lkml/2020/4/10/47
At first I posted a fix (https://lkml.org/lkml/2020/4/21/1318) trying
to resolve the issue from hv_storvsc, but with the help of
Bart Van Assche, I realized it's better to fix software_resume(),
since this looks like a generic issue, not only pertaining to SCSI.
Cc: All applicable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 6dbeedb7354cc..daf3ea9d81de8 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -898,6 +898,13 @@ static int software_resume(void)
error = freeze_processes();
if (error)
goto Close_Finish;
+
+ error = freeze_kernel_threads();
+ if (error) {
+ thaw_processes();
+ goto Close_Finish;
+ }
+
error = load_image_and_restore();
thaw_processes();
Finish:
