This is a note to let you know that I've just added the patch titled
scsi: core: Clear driver private data when retrying request
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
scsi-core-clear-driver-private-data-when-retrying-re.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a55b12cb7d3b0d403df8996092c40cbe2aa81b51
Author: Ye Bin <yebin10@xxxxxxxxxx>
Date: Mon Feb 17 10:16:28 2025 +0800
scsi: core: Clear driver private data when retrying request
[ Upstream commit dce5c4afd035e8090a26e5d776b1682c0e649683 ]
After commit 1bad6c4a57ef ("scsi: zero per-cmd private driver data for each
MQ I/O"), the xen-scsifront/virtio_scsi/snic drivers all removed code that
explicitly zeroed driver-private command data.
In combination with commit 464a00c9e0ad ("scsi: core: Kill DRIVER_SENSE"),
after virtio_scsi performs a capacity expansion, the first request will
return a unit attention to indicate that the capacity has changed. And then
the original command is retried. As driver-private command data was not
cleared, the request would return UA again and eventually time out and fail.
Zero driver-private command data when a request is retried.
Fixes: f7de50da1479 ("scsi: xen-scsifront: Remove code that zeroes driver-private command data")
Fixes: c2bb87318baa ("scsi: virtio_scsi: Remove code that zeroes driver-private command data")
Fixes: c3006a926468 ("scsi: snic: Remove code that zeroes driver-private command data")
Signed-off-by: Ye Bin <yebin10@xxxxxxxxxx>
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
Link: https://lore.kernel.org/r/20250217021628.2929248-1-yebin@xxxxxxxxxxxxxxx
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index ddaffaea2c32c..c8be41d8eb247 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1532,13 +1532,6 @@ static blk_status_t scsi_prepare_cmd(struct request *req)
if (in_flight)
__set_bit(SCMD_STATE_INFLIGHT, &cmd->state);
- /*
- * Only clear the driver-private command data if the LLD does not supply
- * a function to initialize that data.
- */
- if (!shost->hostt->init_cmd_priv)
- memset(cmd + 1, 0, shost->hostt->cmd_size);
-
cmd->prot_op = SCSI_PROT_NORMAL;
if (blk_rq_bytes(req))
cmd->sc_data_direction = rq_dma_dir(req);
@@ -1675,6 +1668,13 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,
if (!scsi_host_queue_ready(q, shost, sdev, cmd))
goto out_dec_target_busy;
+ /*
+ * Only clear the driver-private command data if the LLD does not supply
+ * a function to initialize that data.
+ */
+ if (shost->hostt->cmd_size && !shost->hostt->init_cmd_priv)
+ memset(cmd + 1, 0, shost->hostt->cmd_size);
+
if (!(req->rq_flags & RQF_DONTPREP)) {
ret = scsi_prepare_cmd(req);
if (ret != BLK_STS_OK)
