Re: Fwd: Waking up from resume locks up on sr device

[Damien Le Moal <dlemoal@kernel.org>]

On 6/14/23 14:37, Kai-Heng Feng wrote:
> On Wed, Jun 14, 2023 at 12:49 PM Damien Le Moal <dlemoal@kernel.org> wrote:
>>
>> On 6/11/23 18:05, Joe Breuer wrote:
>>> I'm the reporter of this issue.
>>>
>>> I just tried this patch against 6.3.4, and it completely fixes my
>>> suspend/resume issue.
>>>
>>> The optical drive stays usable after resume, even suspending/resuming
>>> during playback of CDDA content works flawlessly and playback resumes
>>> seamlessly after system resume.
>>>
>>> So, from my perspective: Good one!
>>
>> In place of Bart's fix, could you please try this patch ?
> 
> Issue still persists at my end, when /sys/power/pm_async is 0.
> device_pm_wait_for_dev() in its current form is only usable for async case.

Can you try this horrible hack to see if it works:

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 9e79998e3958..87c093775a90 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -4590,6 +4590,7 @@ void ata_scsi_dev_rescan(struct work_struct *work)
        ata_for_each_link(link, ap, EDGE) {
                ata_for_each_dev(dev, link, ENABLED) {
                        struct scsi_device *sdev = dev->sdev;
+                       struct device *sgdev;

                        if (!sdev)
                                continue;
@@ -4597,7 +4598,10 @@ void ata_scsi_dev_rescan(struct work_struct *work)
                                continue;

                        spin_unlock_irqrestore(ap->lock, flags);
-                       scsi_rescan_device(&(sdev->sdev_gendev));
+
+                       sgdev = &sdev->sdev_gendev;
+                       wait_for_completion(&sgdev->power.completion);
+                       scsi_rescan_device(sgdev);
                        scsi_device_put(sdev);
                        spin_lock_irqsave(ap->lock, flags);
                }



> 
> Kai-Heng
> 
>>
>> diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
>> index b80e68000dd3..a81eb4f882ab 100644
>> --- a/drivers/ata/libata-eh.c
>> +++ b/drivers/ata/libata-eh.c
>> @@ -4006,9 +4006,32 @@ static void ata_eh_handle_port_resume(struct
>> ata_port *ap)
>>         /* tell ACPI that we're resuming */
>>         ata_acpi_on_resume(ap);
>>
>> -       /* update the flags */
>>         spin_lock_irqsave(ap->lock, flags);
>> +
>> +       /* Update the flags */
>>         ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
>> +
>> +       /*
>> +        * Resuming the port will trigger a rescan of the ATA device(s)
>> +        * connected to it. Before scheduling the rescan, make sure that
>> +        * the associated scsi device(s) are fully resumed as well.
>> +        */
>> +       ata_for_each_link(link, ap, HOST_FIRST) {
>> +               ata_for_each_dev(dev, link, ENABLED) {
>> +                       struct scsi_device *sdev = dev->sdev;
>> +
>> +                       if (!sdev)
>> +                               continue;
>> +                       if (scsi_device_get(sdev))
>> +                               continue;
>> +
>> +                       spin_unlock_irqrestore(ap->lock, flags);
>> +                       device_pm_wait_for_dev(&ap->tdev,
>> +                                              &sdev->sdev_gendev);
>> +                       scsi_device_put(sdev);
>> +                       spin_lock_irqsave(ap->lock, flags);
>> +               }
>> +       }
>>         spin_unlock_irqrestore(ap->lock, flags);
>>  }
>>  #endif /* CONFIG_PM */
>>
>> Thanks !
>>
>> --
>> Damien Le Moal
>> Western Digital Research
>>

-- 
Damien Le Moal
Western Digital Research