diff mbox series

[v3] scsi: ufs: fix broken hba->outstanding_tasks

Message ID 1566222208-19890-1-git-send-email-stanley.chu@mediatek.com (mailing list archive)
State Mainlined
Commit b557217c8475f40bc765ee20ff6b3b9124c8a4fe
Headers show
Series [v3] scsi: ufs: fix broken hba->outstanding_tasks | expand

Commit Message

Stanley Chu Aug. 19, 2019, 1:43 p.m. UTC 
Currently bits in hba->outstanding_tasks are cleared only after their
corresponding task management commands are successfully done by
__ufshcd_issue_tm_cmd().

If timeout happens in a task management command, its corresponding
bit in hba->outstanding_tasks will not be cleared until next task
management command with the same tag used successfully finishes.

This is wrong and can lead to some issues, like power issue.
For example, ufshcd_release() and ufshcd_gate_work() will do nothing
if hba->outstanding_tasks is not zero even if both UFS host and devices
are actually idle.

Solution is referried from error handling of device commands: bits in
hba->outstanding_tasks shall be cleared regardless of their execution
results.

Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Chun-Hung Wu <chun-hung.wu@mediatek.com>
---
 drivers/scsi/ufs/ufshcd.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

Comments

Avri Altman Aug. 20, 2019, 6:59 a.m. UTC | #1 
> 
> Currently bits in hba->outstanding_tasks are cleared only after their
> corresponding task management commands are successfully done by
> __ufshcd_issue_tm_cmd().
> 
> If timeout happens in a task management command, its corresponding
> bit in hba->outstanding_tasks will not be cleared until next task
> management command with the same tag used successfully finishes.
> 
> This is wrong and can lead to some issues, like power issue.
> For example, ufshcd_release() and ufshcd_gate_work() will do nothing
> if hba->outstanding_tasks is not zero even if both UFS host and devices
> are actually idle.
> 
> Solution is referried from error handling of device commands: bits in
> hba->outstanding_tasks shall be cleared regardless of their execution
> results.
> 
> Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
> Signed-off-by: Chun-Hung Wu <chun-hung.wu@mediatek.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Martin K. Petersen Aug. 29, 2019, 9:50 p.m. UTC | #2 
Stanley,

> Currently bits in hba->outstanding_tasks are cleared only after their
> corresponding task management commands are successfully done by
> __ufshcd_issue_tm_cmd().

Applied to 5.4/scsi-queue. Thank you!
diff mbox series

Patch

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 3804a704e565..30b752c61b97 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5676,13 +5676,12 @@  static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba,
 		memcpy(treq, hba->utmrdl_base_addr + free_slot, sizeof(*treq));
 
 		ufshcd_add_tm_upiu_trace(hba, task_tag, "tm_complete");
-
-		spin_lock_irqsave(hba->host->host_lock, flags);
-		__clear_bit(free_slot, &hba->outstanding_tasks);
-		spin_unlock_irqrestore(hba->host->host_lock, flags);
-
 	}
 
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	__clear_bit(free_slot, &hba->outstanding_tasks);
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+
 	clear_bit(free_slot, &hba->tm_condition);
 	ufshcd_put_tm_slot(hba, free_slot);
 	wake_up(&hba->tm_tag_wq);