[PATCH 1/2] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns

2021-01-06 Thread Jaegeuk Kim
When gate_work/ungate_work gets an error during hibern8_enter or exit,
 ufshcd_err_handler()
   ufshcd_scsi_block_requests()
   ufshcd_reset_and_restore()
 ufshcd_clear_ua_wluns() -> stuck
   ufshcd_scsi_unblock_requests()

In order to avoid it, ufshcd_clear_ua_wluns() can be called per recovery flows
such as suspend/resume, link_recovery, and error_handler.

Fixes: 1918651f2d7e ("scsi: ufs: Clear UAC for RPMB after ufshcd resets")
Signed-off-by: Jaegeuk Kim 
---
 drivers/scsi/ufs/ufshcd.c | 15 ++-
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index bedb822a40a3..1678cec08b51 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3996,6 +3996,8 @@ int ufshcd_link_recovery(struct ufs_hba *hba)
if (ret)
dev_err(hba->dev, "%s: link recovery failed, err %d",
__func__, ret);
+   else
+   ufshcd_clear_ua_wluns(hba);
 
return ret;
 }
@@ -6003,6 +6005,9 @@ static void ufshcd_err_handler(struct work_struct *work)
ufshcd_scsi_unblock_requests(hba);
ufshcd_err_handling_unprepare(hba);
up(>eh_sem);
+
+   if (!err && needs_reset)
+   ufshcd_clear_ua_wluns(hba);
 }
 
 /**
@@ -6940,14 +6945,11 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba 
*hba)
ufshcd_set_clk_freq(hba, true);
 
err = ufshcd_hba_enable(hba);
-   if (err)
-   goto out;
 
/* Establish the link again and restore the device */
-   err = ufshcd_probe_hba(hba, false);
if (!err)
-   ufshcd_clear_ua_wluns(hba);
-out:
+   err = ufshcd_probe_hba(hba, false);
+
if (err)
dev_err(hba->dev, "%s: Host init failed %d\n", __func__, err);
ufshcd_update_evt_hist(hba, UFS_EVT_HOST_RESET, (u32)err);
@@ -8777,6 +8779,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum 
ufs_pm_op pm_op)
ufshcd_resume_clkscaling(hba);
hba->clk_gating.is_suspended = false;
hba->dev_info.b_rpm_dev_flush_capable = false;
+   ufshcd_clear_ua_wluns(hba);
ufshcd_release(hba);
 out:
if (hba->dev_info.b_rpm_dev_flush_capable) {
@@ -8887,6 +8890,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum 
ufs_pm_op pm_op)
cancel_delayed_work(>rpm_dev_flush_recheck_work);
}
 
+   ufshcd_clear_ua_wluns(hba);
+
/* Schedule clock gating in case of no access to UFS device yet */
ufshcd_release(hba);
 
-- 
2.29.2.729.g45daf8777d-goog



[PATCH 1/2] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns

2021-01-06 Thread Jaegeuk Kim
When gate_work/ungate_work gets an error during hibern8_enter or exit,
 ufshcd_err_handler()
   ufshcd_scsi_block_requests()
   ufshcd_reset_and_restore()
 ufshcd_clear_ua_wluns() -> stuck
   ufshcd_scsi_unblock_requests()

In order to avoid it, ufshcd_clear_ua_wluns() can be called per recovery flows
such as suspend/resume, link_recovery, and error_handler.

Fixes: 1918651f2d7e ("scsi: ufs: Clear UAC for RPMB after ufshcd resets")
Signed-off-by: Jaegeuk Kim 
---
 drivers/scsi/ufs/ufshcd.c | 15 ++-
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index bedb822a40a3..1678cec08b51 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3996,6 +3996,8 @@ int ufshcd_link_recovery(struct ufs_hba *hba)
if (ret)
dev_err(hba->dev, "%s: link recovery failed, err %d",
__func__, ret);
+   else
+   ufshcd_clear_ua_wluns(hba);
 
return ret;
 }
@@ -6003,6 +6005,9 @@ static void ufshcd_err_handler(struct work_struct *work)
ufshcd_scsi_unblock_requests(hba);
ufshcd_err_handling_unprepare(hba);
up(>eh_sem);
+
+   if (!err && needs_reset)
+   ufshcd_clear_ua_wluns(hba);
 }
 
 /**
@@ -6940,14 +6945,11 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba 
*hba)
ufshcd_set_clk_freq(hba, true);
 
err = ufshcd_hba_enable(hba);
-   if (err)
-   goto out;
 
/* Establish the link again and restore the device */
-   err = ufshcd_probe_hba(hba, false);
if (!err)
-   ufshcd_clear_ua_wluns(hba);
-out:
+   err = ufshcd_probe_hba(hba, false);
+
if (err)
dev_err(hba->dev, "%s: Host init failed %d\n", __func__, err);
ufshcd_update_evt_hist(hba, UFS_EVT_HOST_RESET, (u32)err);
@@ -8777,6 +8779,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum 
ufs_pm_op pm_op)
ufshcd_resume_clkscaling(hba);
hba->clk_gating.is_suspended = false;
hba->dev_info.b_rpm_dev_flush_capable = false;
+   ufshcd_clear_ua_wluns(hba);
ufshcd_release(hba);
 out:
if (hba->dev_info.b_rpm_dev_flush_capable) {
@@ -8887,6 +8890,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum 
ufs_pm_op pm_op)
cancel_delayed_work(>rpm_dev_flush_recheck_work);
}
 
+   ufshcd_clear_ua_wluns(hba);
+
/* Schedule clock gating in case of no access to UFS device yet */
ufshcd_release(hba);
 
-- 
2.29.2.729.g45daf8777d-goog