If somehow no interrupt notification is raised for a completed request
and its doorbell bit is cleared by host, UFS driver needs to cleanup
its outstanding bit in ufshcd_abort().
Otherwise, system may crash by below abnormal flow:
After this request is requeued by SCSI layer with its
outstanding bit set, the next completed request will trigger
ufshcd_transfer_req_compl() to handle all "completed outstanding
bits". In this time, the "abnormal outstanding bit" will be detected
and the "requeued request" will be chosen to execute request
post-processing flow. This is wrong and blk_finish_request() will
BUG_ON because this request is still in the request queue.
Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 52abe82a1166..f173ad1bd79f 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6462,7 +6462,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
/* command completed already */
dev_err(hba->dev, "%s: cmd at tag %d successfully cleared from DB.\n",
__func__, tag);
- goto out;
+ goto cleanup;
} else {
dev_err(hba->dev,
"%s: no response from device. tag = %d, err %d\n",
@@ -6496,6 +6496,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
goto out;
}
+cleanup:
scsi_dma_unmap(cmd);
spin_lock_irqsave(host->host_lock, flags);
--
2.18.0
