scsi: core: Fix command pass through retry regression

scsi_check_passthrough() is always called, but it doesn't check for if a
command completed successfully. As a result, if a command was successful and
the caller used SCMD_FAILURE_RESULT_ANY to indicate what failures it wanted
to retry, we will end up retrying the command. This will cause delays during
device discovery because of the command being sent multiple times. For some
USB devices it can also cause the wrong device size to be used.

This patch adds a check for if the command was successful. If it is we
return immediately instead of trying to match a failure.

Fixes: 994724e6b3f0 ("scsi: core: Allow passthrough to request midlayer retries")
Reported-by: Kris Karas <bugs-a21@moonlit-rail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219652
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20250107010220.7215-1-michael.christie@oracle.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index adee6f60c966553ffb9dc632b12646d7225477d5..0cc6a0f77b09229418a092b793bf077cd9ad440b 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -210,6 +210,9 @@ static int scsi_check_passthrough(struct scsi_cmnd *scmd,
        struct scsi_sense_hdr sshdr;
        enum sam_status status;
 
+       if (!scmd->result)
+               return 0;
+
        if (!failures)
                return 0;