On 8/17/22 01:34, Michael Wu wrote:
When accessing storage device via an USB card reader, a block I/O error
occurs during resume:
PM: suspend exit
sd 0: 0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x00 driverbyte
=0x08
sd 0: 0:0:0: [sda] tag#0 Sense Key : 0x6 [current]
sd 0: 0:0:0: [sda] tag#0 ASC=0x28 ASCQ=0x0
sd 0: 0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 17 ce e1 00 00 f0 00
blk_update_request: I/O error, dev sda, sector 1560289 op 0x0:(READ) flags
0x84700 phys_seg 19 prio class 0
sd 0: 0:0:0: [sda] tag#0 device offline or changed
Fix it by changing the action in scsi_io_completion_action() from
ACTION_FAIL to ACTION_RETRY by adding the condition `cmd->device->
lockable`.
Signed-off-by: Michael Wu <michael@xxxxxxxxxxxxxxxxx>
---
drivers/scsi/scsi_lib.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 4dbd29ab1dcc..4bc480721947 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -704,7 +704,8 @@ static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result)
} else if (sense_valid && sense_current) {
switch (sshdr.sense_key) {
case UNIT_ATTENTION:
- if (cmd->device->removable) {
+ if (cmd->device->removable &&
+ cmd->device->lockable) {
/* Detected disc change. Set a bit
* and quietly refuse further access.
*/
To me the above doesn't look like a good way to address this. I don't
see why a device being lockable should control whether or not a unit
attention results in a retry? Shouldn't the decision taken by
scsi_io_completion_action() depend on the ASC and ASCQ codes rather than
on whether a device is removable and/or lockable?
BTW, the code modified by the above patch is old. This is what I found
in the 2002 version of scsi_lib.c:
if ((SCpnt->sense_buffer[0] & 0x7f) == 0x70
&& (SCpnt->sense_buffer[2] & 0xf) == UNIT_ATTENTION) {
if (SCpnt->device->removable) {
/* detected disc change. set a bit and quietly refuse
* further access.
*/
SCpnt->device->changed = 1;
SCpnt = scsi_end_request(SCpnt, 0, this_count);
return;
} else {
/*
* Must have been a power glitch, or a
* bus reset. Could not have been a
* media change, so we just retry the
* request and see what happens.
*/
scsi_queue_next_request(q, SCpnt);
return;
}
Bart.
Thanks,
Bart.
