Re: 2.6.1: media change check fails for busy unplugged device

[Andrey Borzenkov <arvidjaar@mail.ru>]

On Tuesday 20 January 2004 02:36, Mike Anderson wrote:
> Andrey Borzenkov [arvidjaar@mail.ru] wrote:
> > If we unplug busy device (consider mounted USB stick) media change check
> > always returns true (no media change happened). It happens because
> >
> > - device state is set to SDEV_DEL and scsi_prep_fn silently kills any
> > request including TEST_UNIT_READY sent by sd_media_changed without
> > propagating any information back to caller
>
> The silently kill would appear to be the issue. The addition of any
> number of additional checks prior to calling scsi_ioctl would not ensure
> that as soon as the last check is done the device state has not changed.
>

But why sdev->online remains set after device has been deleted? It is 
definitely cannot accept any command after that point?

Is it possible to clear sdev->online in scsi_remove_device? That would solve 
the problem.

thank you

-andrey

> We need a change in scsi_wait_req to differentiate that we where not woken
> up from scsi_wait_done, but from end_that_request_last.
>
> One way would be to check if rq_status == RQ_SCSI_DONE. I did not see
> anything on the request to indicate it was BLKPREP_KILL'd.
>
> James has worked more on the scsi_prep_fn so maybe he has another
> suggestion.
>
> -andmike
> --
> Michael Anderson
> andmike@us.ibm.com