[PATCH v13 0/2] Enable power management for ufs wlun

[Adrian Hunter]

On 30/03/21 1:48 am, Asutosh Das (asd) wrote:
> On 3/24/2021 6:39 PM, Asutosh Das wrote:
>> This patch attempts to fix a deadlock in ufs while sending SSU.
>> Recently, blk_queue_enter() added a check to not process requests if the
>> queue is suspended. That leads to a resume of the associated device which
>> is suspended. In ufs, that device is ufs device wlun and it's parent is
>> ufs_hba. This resume tries to resume ufs device wlun which in turn tries
>> to resume ufs_hba, which is already in the process of suspending, thus
>> causing a deadlock.
>>
>> This patch takes care of:
>> * Suspending the ufs device lun only after all other luns are suspended
>> * Sending SSU during ufs device wlun suspend
>> * Clearing uac for rpmb and ufs device wlun
>> * Not sending commands to the device during host suspend
>>
>> v12 -> v13:
>> - Addressed Adrian's comments
>>    * Paired pm_runtime_get_noresume() with pm_runtime_put()
>>    * no rpm_autosuspend for ufs device wlun
>>    * Moved runtime-pm init functionality to ufshcd_wl_probe()
>> - Addressed Bart's comments
>>    * Expanded abbrevs in commit message
>>
> 
> Hi Adrian
> I did a limited testing on your fix in the pm framework along with this v13 patchset. I couldn't reproduce the issue.
> 
> I'd appreciate if you can please take a look at the v13 changes.
> If all looks good in that, I'd do an extensive testing.

I made a couple of comments on the patch, but nothing major.