Re: [PATCH v4 1/1] scsi: pm: Balance pm_only counter of request queue during system resume

From: Bart Van Assche
Date: Thu May 07 2020 - 00:32:45 EST


On 2020-05-05 21:55, Can Guo wrote:
> During system resume, scsi_resume_device() decreases a request queue's
> pm_only counter if the scsi device was quiesced before. But after that,
> if the scsi device's RPM status is RPM_SUSPENDED, the pm_only counter is
> still held (non-zero). Current scsi resume hook only sets the RPM status
> of the scsi device and its request queue to RPM_ACTIVE, but leaves the
> pm_only counter unchanged. This may make the request queue's pm_only
> counter remain non-zero after resume hook returns, hence those who are
> waiting on the mq_freeze_wq would never be woken up. Fix this by calling
> blk_post_runtime_resume() if a sdev's RPM status was RPM_SUSPENDED.

Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>

Thank you for having root-caused and fixed this!

Bart.