Skip to contentSkip to conversation

scsi: ufs: core: Flush exception handling work when RPM level is zero

PATCH Applied Thomas Yen 4 participants 5 messages Jan 29 – Feb 8

Subsystems (3)
Stable branch SCSI UFS host controller
lore
Share & tools
lore

Thomas Yen

author
#0 lore raw

PATCH v4 1/1 scsi: ufs: core: Flush exception handling work when RPM level is zero

Ensure that the exception event handling work is explicitly flushed during suspend when the runtime power management level is set to UFS_PM_LVL_0.

When the RPM level is zero, the device power mode and link state both remain active. Previously, the UFS core driver bypassed flushing exception event handling jobs in this configuration. This created a race condition where the driver could attempt to access the host controller to handle an exception after the system had already entered a deep power-down state, resulting in a system crash.

Explicitly flush this work and disable auto BKOPs before the suspend callback proceeds. This guarantees that pending exception tasks complete and prevents illegal hardware access during the power-down sequence.

Fixes 57d104c153d3 ("scsi: ufs: ufshcd: Fix link state during system suspend")
Signed-off-by Thomas Yen <[email protected]>
Cc Stable Tree <[email protected]>

---
v4:
- Add Fixes tag.
v3:
- Add logic to disable BKOPs.
v2:
- Add Cc: stable tag.
- Reformat commit message text for better line wrapping.

 drivers/ufs/core/ufshcd.c | 2 ++
 1 file changed, 2 insertions(+)
drivers/ufs/core/ufshcd.c +2 -0
index 0369043ca010..8c88dd5c2cca 100644
@@ -9997,6 +9997,8 @@ static int __ufshcd_wl_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 
 	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
 			req_link_state == UIC_LINK_ACTIVE_STATE) {
+		ufshcd_disable_auto_bkops(hba);
+		flush_work(&hba->eeh_work);
 		goto vops_suspend;
 	}

base-commit: a48ca06cf343423faa01c573aeafba9fa5f92577

Signature · 1 line
2.53.0.rc1.225.gd81095ad13-goog
Reviewed-by on v4 1/1
#1 lore raw
Quoted 11 lines · Thomas Yen
drivers/ufs/core/ufshcd.c +0 -0
index 0369043ca010..8c88dd5c2cca 100644
@@ -9997,6 +9997,8 @@ static int __ufshcd_wl_suspend(struct ufs_hba
 *hba, enum ufs_pm_op pm_op)


  if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE && req_link_state == UIC_LINK_ACTIVE_STATE) {

drivers/ufs/core/ufshcd.c +2 -0
+		ufshcd_disable_auto_bkops(hba);
+		flush_work(&hba->eeh_work);
Quoted 5 lines

  goto vops_suspend;
  }

Reviewed-by Peter Wang <[email protected]>

If you have the next version, please feel free to add my review tag. Thanks.

reviewer Reviewed-by on v4 1/1
#2 lore raw
In reply to Thomas Yen

drivers/ufs/core/ufshcd.c static int __ufshcd_wl_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) · line 10003

Quoted 12 lines · Thomas Yen
drivers/ufs/core/ufshcd.c +2 -0
index 0369043ca010..8c88dd5c2cca 100644
@@ -9997,6 +9997,8 @@ static int __ufshcd_wl_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 
  	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
  			req_link_state == UIC_LINK_ACTIVE_STATE) {
+		ufshcd_disable_auto_bkops(hba);
+		flush_work(&hba->eeh_work);
  		goto vops_suspend;
  	}
Reviewed-by Bart Van Assche <[email protected]>
#3 lore raw
In reply to Thomas Yen

Thomas,

Quoted 3 lines

Ensure that the exception event handling work is explicitly flushed during suspend when the runtime power management level is set to UFS_PM_LVL_0.

Replied to the wrong mail, I applied v4. Thanks!

Signature · 1 line
Martin K. Petersen
Applied
#4 lore raw
In reply to Thomas Yen
Quoted 4 lines · Thomas Yen

Ensure that the exception event handling work is explicitly flushed during suspend when the runtime power management level is set to UFS_PM_LVL_0.

Quoted 8 lines

When the RPM level is zero, the device power mode and link state both remain active. Previously, the UFS core driver bypassed flushing exception event handling jobs in this configuration. This created a race condition where the driver could attempt to access the host controller to handle an exception after the system had already entered a deep power-down state, resulting in a system crash.

[...]

Applied to 6.20/scsi-queue, thanks!

[1/1] scsi: ufs: core: Flush exception handling work when RPM level is zero

      https://git.kernel.org/mkp/scsi/c/f8ef441811ec
Signature · 1 line
Martin K. Petersen