On 4/7/2021 3:21 AM, Adrian Hunter wrote:
On 6/04/21 8:52 pm, Asutosh Das wrote:
During runtime-suspend of ufs host, the scsi devices are
already suspended and so are the queues associated with them.
But the ufs host sends SSU (START_STOP_UNIT) to wlun
during its runtime-suspend.
During the process blk_queue_enter checks if the queue is not in
suspended state. If so, it waits for the queue to resume, and never
comes out of it.
The commit
(d55d15a33: scsi: block: Do not accept any requests while suspended)
adds the check if the queue is in suspended state in blk_queue_enter().
Call trace:
__switch_to+0x174/0x2c4
__schedule+0x478/0x764
schedule+0x9c/0xe0
blk_queue_enter+0x158/0x228
blk_mq_alloc_request+0x40/0xa4
blk_get_request+0x2c/0x70
__scsi_execute+0x60/0x1c4
ufshcd_set_dev_pwr_mode+0x124/0x1e4
ufshcd_suspend+0x208/0x83c
ufshcd_runtime_suspend+0x40/0x154
ufshcd_pltfrm_runtime_suspend+0x14/0x20
pm_generic_runtime_suspend+0x28/0x3c
__rpm_callback+0x80/0x2a4
rpm_suspend+0x308/0x614
rpm_idle+0x158/0x228
pm_runtime_work+0x84/0xac
process_one_work+0x1f0/0x470
worker_thread+0x26c/0x4c8
kthread+0x13c/0x320
ret_from_fork+0x10/0x18
Fix this by registering ufs device wlun as a scsi driver and
registering it for block runtime-pm. Also make this as a
supplier for all other luns. That way, this device wlun
suspends after all the consumers and resumes after
hba resumes.
Co-developed-by: Can Guo <cang@xxxxxxxxxxxxxx>
Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
Signed-off-by: Asutosh Das <asutoshd@xxxxxxxxxxxxxx>
---
v15 seems to be missing the updates to ufs_debugfs_get/put_user_access
that were in v14:
@@ -60,14 +60,14 @@ __acquires(&hba->host_sem)
up(&hba->host_sem);
return -EBUSY;
}
- pm_runtime_get_sync(hba->dev);
+ scsi_autopm_get_device(hba->sdev_ufs_device);
return 0;
}
static void ufs_debugfs_put_user_access(struct ufs_hba *hba)
__releases(&hba->host_sem)
{
- pm_runtime_put_sync(hba->dev);
+ scsi_autopm_put_device(hba->sdev_ufs_device);
up(&hba->host_sem);
}
Also from last comments, the issue below:
<SNIP>
+#ifdef CONFIG_PM_SLEEP
+static int ufshcd_wl_poweroff(struct device *dev)
+{
+ ufshcd_wl_shutdown(dev);
This turned out to be wrong. This is a PM op and SCSI has already
quiesced the sdev's. All that is needed is:
__ufshcd_wl_suspend(hba, UFS_SHUTDOWN_PM);
Yikes! Thanks, let me fix this and push the correct series.
-asd
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