Re: [PATCH 2/2] dm: Avoid use-after-free of a mapped device

[Mike Snitzer <snitzer@redhat.com>]

On Fri, Feb 22 2013 at  6:22am -0500,
Bart Van Assche <bvanassche@acm.org> wrote:

> On 02/22/13 12:08, Mike Snitzer wrote:
> >On Fri, Feb 22 2013 at  5:47am -0500,
> >Bart Van Assche <bvanassche@acm.org> wrote:
> >
> >>As the comment above rq_completed() explains, md members must
> >>not be touched after the dm_put() at the end of that function
> >>has been invoked. Avoid that the md->queue can be run
> >>asynchronously after the last md reference has been dropped by
> >>running that queue synchronously.
> >
> >Your commit header should probably reference commit
> >a8c32a5c98943d370ea606a2e7dc04717eb92206 ("dm: fix deadlock with request
> >based dm and queue request_fn recursion") and cc: stable with "v3.7+"
> >guidance.
> >
> >Acked-by: Mike Snitzer <snitzer@redhat.com>
> 
> Hello Mike,
> 
> Thanks for reviewing this patch and for the ack. Regarding the
> stable tag: had you noticed that commit a8c32a5 had a "Cc: stable"
> tag itself and hence probably has already been backported to kernels
> older than v3.7 ?

Ah yes.  Good point.

Jens, since this DM change is dependent on Bart's 1/2 block patch it'd
be ideal if you could pick up both of these patches for v3.9.

Thanks,
Mike