On 05/04/2012 03:16 PM, Mike Christie wrote:
> On 05/04/2012 10:06 AM, Bart Van Assche wrote:
>> diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
>> index 42c35ff..f8fc240 100644
>> --- a/drivers/scsi/scsi_sysfs.c
>> +++ b/drivers/scsi/scsi_sysfs.c
>> @@ -955,12 +955,20 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
>> void __scsi_remove_device(struct scsi_device *sdev)
>> {
>> struct device *dev = &sdev->sdev_gendev;
>> + struct request_queue *q = sdev->request_queue;
>> +
>> + /*
>> + * Stop accepting new requests before tearing down the
>> + * device. Note: the actual queue deallocation happens in
>> + * scsi_device_dev_release_usercontext().
>> + */
>> + blk_cleanup_queue(q);
>>
>> if (sdev->is_visible) {
>> if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
>> return;
>>
>> - bsg_unregister_queue(sdev->request_queue);
>> + bsg_unregister_queue(q);
>> device_unregister(&sdev->sdev_dev);
>> transport_remove_device(dev);
>> device_del(dev);
>> @@ -971,8 +979,6 @@ void __scsi_remove_device(struct scsi_device *sdev)
>
> My fault. The blk_cleanup_queue call should be right before the
> scsi_device_set_state(sdev, SDEV_DEL); call in this function.
>
> It needs to be after the device_del call, because that triggers the SCSI
> ULD removal which can send IO.
>
I made the attached patch. It allows the scsi ULD removal IO to execute
ok. I tested with iscsi devices that have write caches.
With your patch I get:
Apr 27 19:09:51 noisyr6 kernel: sd 11:0:0:1: [sdc] Synchronizing SCSI cache
Apr 27 19:09:51 noisyr6 kernel: sd 11:0:0:1: [sdc] Result:
hostbyte=DID_TRANSPORT_FAILFAST driverbyte=DRIVER_OK
With my patch I just get:
May 4 16:29:27 noisyr6 kernel: sd 8:0:0:1: [sdc] Synchronizing SCSI cache
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 42c35ff..11dc3ff 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -955,24 +955,30 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
void __scsi_remove_device(struct scsi_device *sdev)
{
struct device *dev = &sdev->sdev_gendev;
+ struct request_queue *q = sdev->request_queue;
if (sdev->is_visible) {
if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
return;
- bsg_unregister_queue(sdev->request_queue);
+ bsg_unregister_queue(q);
device_unregister(&sdev->sdev_dev);
transport_remove_device(dev);
device_del(dev);
} else
put_device(&sdev->sdev_dev);
+ /*
+ * Stop accepting new requests before tearing down the
+ * queue. Note: the actual queue deallocation happens in
+ * scsi_device_dev_release_usercontext().
+ */
+ blk_cleanup_queue(q);
+
scsi_device_set_state(sdev, SDEV_DEL);
if (sdev->host->hostt->slave_destroy)
sdev->host->hostt->slave_destroy(sdev);
transport_destroy_device(dev);
- /* Freeing the queue signals to block that we're done */
- blk_cleanup_queue(sdev->request_queue);
put_device(dev);
}
