The SCSI layer can go into an ugly loop if you ignore that a device
is gone. You need to report an error in the command rather than
in the return value of the queue method.
We need to specifically check for ENODEV. The issue goes
back to the introduction of the driver.
v2: reorder patches
Fixes: 115bb1ffa54c3 ("USB: Add UAS driver")
Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx>
---
drivers/usb/storage/uas.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index d592071119ba..13696f03f800 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -662,8 +662,7 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
if (devinfo->resetting) {
cmnd->result = DID_ERROR << 16;
cmnd->scsi_done(cmnd);
- spin_unlock_irqrestore(&devinfo->lock, flags);
- return 0;
+ goto zombie;
}
/* Find a free uas-tag */
@@ -699,6 +698,16 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
err = uas_submit_urbs(cmnd, devinfo);
+ /*
+ * in case of fatal errors the SCSI layer is peculiar
+ * a command that has finished is a success for the purpose
+ * of queueing, no matter how fatal the error
+ */
+ if (err == -ENODEV) {
+ cmnd->result = DID_ERROR << 16;
+ cmnd->scsi_done(cmnd);
+ goto zombie;
+ }
if (err) {
/* If we did nothing, give up now */
if (cmdinfo->state & SUBMIT_STATUS_URB) {
@@ -709,6 +718,7 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
}
devinfo->cmnd[idx] = cmnd;
+zombie:
spin_unlock_irqrestore(&devinfo->lock, flags);
return 0;
}
--
2.16.4
