From: Alexander Atanasov <alexander.atanasov@virtuozzo.com>
Date: Fri, 15 Dec 2023 14:10:08 +0200
Subject: scsi: core: Always send batch on reset or error handling command
Git-commit: 066c5b46b6eaf2f13f80c19500dbb3b84baabb33
Patch-mainline: v6.7-rc7
References: git-fixes

In commit 8930a6c20791 ("scsi: core: add support for request batching") the
block layer bd->last flag was mapped to SCMD_LAST and used as an indicator
to send the batch for the drivers that implement this feature. However, the
error handling code was not updated accordingly.

scsi_send_eh_cmnd() is used to send error handling commands and request
sense. The problem is that request sense comes as a single command that
gets into the batch queue and times out. As a result the device goes
offline after several failed resets. This was observed on virtio_scsi
during a device resize operation.

[  496.316946] sd 0:0:4:0: [sdd] tag#117 scsi_eh_0: requesting sense
[  506.786356] sd 0:0:4:0: [sdd] tag#117 scsi_send_eh_cmnd timeleft: 0
[  506.787981] sd 0:0:4:0: [sdd] tag#117 abort

To fix this always set SCMD_LAST flag in scsi_send_eh_cmnd() and
scsi_reset_ioctl().

Fixes: 8930a6c20791 ("scsi: core: add support for request batching")
Cc: <stable@vger.kernel.org>
Signed-off-by: Alexander Atanasov <alexander.atanasov@virtuozzo.com>
Link: https://lore.kernel.org/r/20231215121008.2881653-1-alexander.atanasov@virtuozzo.com
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Lee Duncan <lduncan@suse.com>
---
 drivers/scsi/scsi_error.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index c67cdcdc3ba8..1223d34c04da 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -1152,6 +1152,7 @@ retry:
 
 	scsi_log_send(scmd);
 	scmd->submitter = SUBMITTED_BY_SCSI_ERROR_HANDLER;
+	scmd->flags |= SCMD_LAST;
 
 	/*
 	 * Lock sdev->state_mutex to avoid that scsi_device_quiesce() can
@@ -2459,6 +2460,7 @@ scsi_ioctl_reset(struct scsi_device *dev, int __user *arg)
 	scsi_init_command(dev, scmd);
 
 	scmd->submitter = SUBMITTED_BY_SCSI_RESET_IOCTL;
+	scmd->flags |= SCMD_LAST;
 	memset(&scmd->sdb, 0, sizeof(scmd->sdb));
 
 	scmd->cmd_len			= 0;