[PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
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 e221add25a7e..29a62552f6f1 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3963,6 +3963,8 @@ 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;
}
@@ -5968,6 +5970,9 @@ 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);
}
/**
@@ -6908,14 +6913,11 @@ 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);
@@ -8745,6 +8747,7 @@ 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) {
@@ -8855,6 +8858,8 @@ 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
RE: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
> > > > > > > In order to avoid it, ufshcd_clear_ua_wluns() can be called per > > > recovery > > > > > > > flows > > > > > > > such as suspend/resume, link_recovery, and error_handler. > > > > > > Not sure that suspend/resume are UAC events? > > > > > > > > > > Could you elaborate a bit? The goal is to clear UAC after UFS reset > > > happens. > > > > So why calling it on every suspend and resume? > > > > > > 1. If UAC was cleared, there's no impact. > > But the command is still sent. > > No, ufshcd_clear_ua_wluns() will return by hba->wlun_dev_clr_ua. > > > > > > 2. ufshcd_link_recovery() can reset UFS directly by ufs_mtk_resume(). > > > 3. ufshcd_suspend can call ufshcd_host_reset_and_restore() as well. > > Seems excessive IMO. > > Why not selectively send when indeed required, e.g. on reset? > > I think hba->wlun_dev_clr_ua is the indicator whether there was a reset or > not. Ahha - I missed that. Thanks for clarifying it. OK Then. Thanks, Avri
Re: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
On 12/21, Avri Altman wrote: > > > > > > On 12/21, Avri Altman wrote: > > > > > > 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. > > > > > Not sure that suspend/resume are UAC events? > > > > > > > > Could you elaborate a bit? The goal is to clear UAC after UFS reset > > happens. > > > So why calling it on every suspend and resume? > > > > 1. If UAC was cleared, there's no impact. > But the command is still sent. No, ufshcd_clear_ua_wluns() will return by hba->wlun_dev_clr_ua. > > > 2. ufshcd_link_recovery() can reset UFS directly by ufs_mtk_resume(). > > 3. ufshcd_suspend can call ufshcd_host_reset_and_restore() as well. > Seems excessive IMO. > Why not selectively send when indeed required, e.g. on reset? I think hba->wlun_dev_clr_ua is the indicator whether there was a reset or not.
RE: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
> > > On 12/21, Avri Altman wrote: > > > > > 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. > > > > Not sure that suspend/resume are UAC events? > > > > > > Could you elaborate a bit? The goal is to clear UAC after UFS reset > happens. > > So why calling it on every suspend and resume? > > 1. If UAC was cleared, there's no impact. But the command is still sent. > 2. ufshcd_link_recovery() can reset UFS directly by ufs_mtk_resume(). > 3. ufshcd_suspend can call ufshcd_host_reset_and_restore() as well. Seems excessive IMO. Why not selectively send when indeed required, e.g. on reset?
Re: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
On 12/21, Avri Altman wrote: > > > > 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. > > > Not sure that suspend/resume are UAC events? > > > > Could you elaborate a bit? The goal is to clear UAC after UFS reset happens. > So why calling it on every suspend and resume? 1. If UAC was cleared, there's no impact. 2. ufshcd_link_recovery() can reset UFS directly by ufs_mtk_resume(). 3. ufshcd_suspend can call ufshcd_host_reset_and_restore() as well. > > > > > > > > > Also the 'fixes' tag is missing. > > > > Added. Thanks, > > > > > > > > Thanks, > > > Avri
RE: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
> > > 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. > > Not sure that suspend/resume are UAC events? > > Could you elaborate a bit? The goal is to clear UAC after UFS reset happens. So why calling it on every suspend and resume? > > > > > Also the 'fixes' tag is missing. > > Added. Thanks, > > > > > Thanks, > > Avri
Re: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
Hi, On 12/20, Avri Altman wrote: > Hi J, > > > > > 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. > Not sure that suspend/resume are UAC events? Could you elaborate a bit? The goal is to clear UAC after UFS reset happens. > > Also the 'fixes' tag is missing. Added. Thanks, > > Thanks, > Avri
Re: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
On 12/21, Can Guo wrote:
> On 2020-12-18 11:31, Jaegeuk Kim wrote:
> > 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.
> >
> > Signed-off-by: Jaegeuk Kim
> > ---
> > drivers/scsi/ufs/ufshcd.c | 14 +-
> > 1 file changed, 9 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> > index e221add25a7e..e711def829cd 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -3963,6 +3963,8 @@ 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;
> > }
> > @@ -5968,6 +5970,8 @@ static void ufshcd_err_handler(struct work_struct
> > *work)
> > ufshcd_scsi_unblock_requests(hba);
> > ufshcd_err_handling_unprepare(hba);
> > up(>eh_sem);
> > +
>
> Maybe add a check like if (!err && needs_reset) as error handler
> also handles non-fatal errors which do not require a full reset
> and restore?
I see. Let me add it in v2.
>
> > + ufshcd_clear_ua_wluns(hba);
> > }
> >
> > /**
> > @@ -6908,14 +6912,11 @@ 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);
> > @@ -8745,6 +8746,7 @@ 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) {
> > @@ -8855,6 +8857,8 @@ 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);
Re: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
On 2020-12-18 11:31, Jaegeuk Kim wrote:
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.
Signed-off-by: Jaegeuk Kim
---
drivers/scsi/ufs/ufshcd.c | 14 +-
1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e221add25a7e..e711def829cd 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3963,6 +3963,8 @@ 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;
}
@@ -5968,6 +5970,8 @@ static void ufshcd_err_handler(struct work_struct
*work)
ufshcd_scsi_unblock_requests(hba);
ufshcd_err_handling_unprepare(hba);
up(>eh_sem);
+
Maybe add a check like if (!err && needs_reset) as error handler
also handles non-fatal errors which do not require a full reset
and restore?
+ ufshcd_clear_ua_wluns(hba);
}
/**
@@ -6908,14 +6912,11 @@ 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);
@@ -8745,6 +8746,7 @@ 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) {
@@ -8855,6 +8857,8 @@ 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);
RE: [PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
Hi J, > > 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. Not sure that suspend/resume are UAC events? Also the 'fixes' tag is missing. Thanks, Avri
[PATCH] scsi: ufs: fix livelock of ufshcd_clear_ua_wluns
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.
Signed-off-by: Jaegeuk Kim
---
drivers/scsi/ufs/ufshcd.c | 14 +-
1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e221add25a7e..e711def829cd 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3963,6 +3963,8 @@ 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;
}
@@ -5968,6 +5970,8 @@ static void ufshcd_err_handler(struct work_struct *work)
ufshcd_scsi_unblock_requests(hba);
ufshcd_err_handling_unprepare(hba);
up(>eh_sem);
+
+ ufshcd_clear_ua_wluns(hba);
}
/**
@@ -6908,14 +6912,11 @@ 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);
@@ -8745,6 +8746,7 @@ 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) {
@@ -8855,6 +8857,8 @@ 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
