On Sat, Jul 2, 2011 at 10:37 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > The second bug, which hit me but apparently not any of you, is that the > request_queue's elevator gets deallocated while it is still in use. > That's because __scsi_remove_device() calls scsi_free_queue(), which > does blk_cleanup_queue(), which calls elevator_exit(), even though the > device file is still open and more requests will be submitted when the > file is closed. > > I'm not sure of the right fix for this. One possibility is to move the > scsi_free_queue() call to scsi_device_dev_release_usercontext(). Or > maybe the elevator_exit() call should be moved to blk_release_queue(). > > Also, I have no idea why this shows up with USB drives but not other > SCSI transports. A fluke of timing? > Not sure it's related, but it sounds like the hotplug failures being seen with libsas hotplug. Have not had a chance yet to track it down further with isci, but mvsas developer Xiangliang Yu is reporting: http://marc.info/?l=linux-scsi&m=130707166512002&w=2 He tracked it down to a suspected regression between .39-rc4 and .39-rc5 but did not finalize the bisect. The isci driver sees this and other signatures all seemingly related to early device tear down and only when pulling a drive with in-flight i/o. -- Dan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
