6.6-stable review patch. If anyone has any objections, please let me know.
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From: Ye Bin yebin10@huawei.com
[ 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@huawei.com Reviewed-by: Bart Van Assche bvanassche@acm.org Link: https://lore.kernel.org/r/20250217021628.2929248-1-yebin@huaweicloud.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/scsi_lib.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index f026377f1cf1c..e6dc2c556fde9 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1570,13 +1570,6 @@ 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); @@ -1743,6 +1736,13 @@ 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)