Hi Jaegeuk,

On 2021-01-07 05:41, Jaegeuk Kim wrote:
From: Jaegeuk Kim <jaeg...@google.com>

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

Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
---
 drivers/scsi/ufs/ufshcd.c | 36 ++++++++++++++++++++++++++++++++----
 1 file changed, 32 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 1678cec08b51..47fc8da3cbf9 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 */

@@ -5899,6 +5902,8 @@ static void ufshcd_err_handler(struct work_struct *work)
         * check if power mode restore is needed.
         */
        if (hba->saved_uic_err & UFSHCD_UIC_PA_GENERIC_ERROR) {
+               ktime_t start = ktime_get();

I don't see the connection btw line-reset and following tmf cmd.
My point is that line-reset is not the only non-fatal error which
leads us to the following tmf cmd. So the wait should be outside
of this check - just put it right before clearing outstanding reqs.

Thanks,
Can Guo.

+
                hba->saved_uic_err &= ~UFSHCD_UIC_PA_GENERIC_ERROR;
                if (!hba->saved_uic_err)
                        hba->saved_err &= ~UIC_ERROR;
@@ -5906,6 +5911,20 @@ static void ufshcd_err_handler(struct work_struct *work)
                if (ufshcd_is_pwr_mode_restore_needed(hba))
                        needs_restore = true;
                spin_lock_irqsave(hba->host->host_lock, flags);
+               /* Wait for IO completion to avoid aborting IOs */
+               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;
+                       }
+               }
+
                if (!hba->saved_err && !needs_restore)
                        goto skip_err_handling;
        }
@@ -6302,9 +6321,13 @@ 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 +6371,11 @@ 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, BLK_MQ_REQ_RESERVED |
+                                               BLK_MQ_REQ_NOWAIT);
+       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);
@@ -9355,6 +9382,7 @@ int ufshcd_init(struct ufs_hba *hba, void
__iomem *mmio_base, unsigned int irq)

        hba->tmf_tag_set = (struct blk_mq_tag_set) {
                .nr_hw_queues   = 1,
+               .reserved_tags  = 1,
                .queue_depth    = hba->nutmrs,
                .ops            = &ufshcd_tmf_ops,
                .flags          = BLK_MQ_F_NO_SCHED,

Reply via email to