On 01/07, Can Guo wrote:
> On 2021-01-07 15:47, Jaegeuk Kim wrote:
> > From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> >
> > This fixes a warning caused by wrong reserve tag usage in
> > __ufshcd_issue_tm_cmd.
> >
> > WARNING: CPU: 7 PID: 7 at block/blk-core.c:630 blk_get_request+0x68/0x70
> > WARNING: CPU: 4 PID: 157 at block/blk-mq-tag.c:82
> > blk_mq_get_tag+0x438/0x46c
> >
> > And, in ufshcd_err_handler(), we can avoid to send tm_cmd before
> > aborting
> > outstanding commands by waiting a bit for IO completion like this.
> >
> > __ufshcd_issue_tm_cmd: task management cmd 0x80 timed-out
> >
> > Fixes: 69a6c269c097 ("scsi: ufs: Use blk_{get,put}_request() to
> > allocate and free TMFs")
> > Fixes: 2355b66ed20c ("scsi: ufs: Handle LINERESET indication in err
> > handler")
>
> Hi Jaegeuk,
>
> Sorry, what is wrong with commit 2355b66ed20c? Clearing pending I/O
> reqs is a general procedure for handling all non-fatal errors.
Without waiting IOs, I hit the below timeout all the time from LINERESET, which
causes UFS stuck permanently, as mentioned in the description.
"__ufshcd_issue_tm_cmd: task management cmd 0x80 timed-out"
>
> Thanks,
> Can Guo.
>
> > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > ---
> > drivers/scsi/ufs/ufshcd.c | 35 +++++++++++++++++++++++++++++++----
> > 1 file changed, 31 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> > index e6e7bdf99cd7..340dd5e515dd 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -44,6 +44,9 @@
> > /* Query request timeout */
> > #define QUERY_REQ_TIMEOUT 1500 /* 1.5 seconds */
> >
> > +/* LINERESET TIME OUT */
> > +#define LINERESET_IO_TIMEOUT_MS (30000) /* 30 sec */
> > +
> > /* Task management command timeout */
> > #define TM_CMD_TIMEOUT 100 /* msecs */
> >
> > @@ -5826,6 +5829,7 @@ static void ufshcd_err_handler(struct work_struct
> > *work)
> > int err = 0, pmc_err;
> > int tag;
> > bool needs_reset = false, needs_restore = false;
> > + ktime_t start;
> >
> > hba = container_of(work, struct ufs_hba, eh_work);
> >
> > @@ -5911,6 +5915,22 @@ static void ufshcd_err_handler(struct work_struct
> > *work)
> > }
> >
> > hba->silence_err_logs = true;
> > +
> > + /* Wait for IO completion for non-fatal errors to avoid aborting IOs
> > */
> > + start = ktime_get();
> > + while (hba->outstanding_reqs) {
> > + ufshcd_complete_requests(hba);
> > + spin_unlock_irqrestore(hba->host->host_lock, flags);
> > + schedule();
> > + spin_lock_irqsave(hba->host->host_lock, flags);
> > + if (ktime_to_ms(ktime_sub(ktime_get(), start)) >
> > + LINERESET_IO_TIMEOUT_MS) {
> > + dev_err(hba->dev, "%s: timeout, outstanding=0x%lx\n",
> > + __func__, hba->outstanding_reqs);
> > + break;
> > + }
> > + }
> > +
> > /* release lock as clear command might sleep */
> > spin_unlock_irqrestore(hba->host->host_lock, flags);
> > /* Clear pending transfer requests */
> > @@ -6302,9 +6322,13 @@ static irqreturn_t ufshcd_intr(int irq, void
> > *__hba)
> > intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS);
> > }
> >
> > - if (enabled_intr_status && retval == IRQ_NONE) {
> > - dev_err(hba->dev, "%s: Unhandled interrupt 0x%08x\n",
> > - __func__, intr_status);
> > + if (enabled_intr_status && retval == IRQ_NONE &&
> > + !ufshcd_eh_in_progress(hba)) {
> > + dev_err(hba->dev, "%s: Unhandled interrupt 0x%08x (0x%08x,
> > 0x%08x)\n",
> > + __func__,
> > + intr_status,
> > + hba->ufs_stats.last_intr_status,
> > + enabled_intr_status);
> > ufshcd_dump_regs(hba, 0, UFSHCI_REG_SPACE_SIZE, "host_regs: ");
> > }
> >
> > @@ -6348,7 +6372,10 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba
> > *hba,
> > * Even though we use wait_event() which sleeps indefinitely,
> > * the maximum wait time is bounded by %TM_CMD_TIMEOUT.
> > */
> > - req = blk_get_request(q, REQ_OP_DRV_OUT, BLK_MQ_REQ_RESERVED);
> > + req = blk_get_request(q, REQ_OP_DRV_OUT, 0);
> > + if (IS_ERR(req))
> > + return PTR_ERR(req);
> > +
> > req->end_io_data = &wait;
> > free_slot = req->tag;
> > WARN_ON_ONCE(free_slot < 0 || free_slot >= hba->nutmrs);
