aboutsummaryrefslogtreecommitdiff
path: root/drivers/scsi
diff options
context:
space:
mode:
authorTejun Heo <htejun@gmail.com>2006-08-08 14:08:59 +0900
committerJeff Garzik <jeff@garzik.org>2006-08-09 01:16:27 -0400
commit22aac0896b1b0b8cabaf00714c55dd12f25d5738 (patch)
treefbae079c8ca9b22103a1e11439ae8b738d756c72 /drivers/scsi
parent85455dd34219376dcc7dce94bea67058f0b7d731 (diff)
[PATCH] libata: clear sdev->locked on door lock failure
SCSI EH locks door if sdev->locked is set. Sometimes door lock command fails continuously (e.g. when medium is not present) and as libata uses EH to acquire sense data, this easily creates a loop where a failed lock door invokes EH and EH issues lock door on completion. This patch clears sdev->locked on door lock failure to break this loop. This problem has been spotted and diagnosed by Unicorn Chang <uchang@tw.ibm.com>. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/scsi')
-rw-r--r--drivers/scsi/libata-scsi.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 7ced41ecde8..e92c31d698f 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -2353,6 +2353,19 @@ static void atapi_qc_complete(struct ata_queued_cmd *qc)
ata_gen_ata_desc_sense(qc);
}
+ /* SCSI EH automatically locks door if sdev->locked is
+ * set. Sometimes door lock request continues to
+ * fail, for example, when no media is present. This
+ * creates a loop - SCSI EH issues door lock which
+ * fails and gets invoked again to acquire sense data
+ * for the failed command.
+ *
+ * If door lock fails, always clear sdev->locked to
+ * avoid this infinite loop.
+ */
+ if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL)
+ qc->dev->sdev->locked = 0;
+
qc->scsicmd->result = SAM_STAT_CHECK_CONDITION;
qc->scsidone(cmd);
ata_qc_free(qc);