blktap: fix reference to freed struct request.

blktap: fix reference to freed struct request.

[Dominic Curran]

blktap: fix reference to freed struct request.

The request will be freed by the call to __blktap_end_rq(), so to
rq->q is invalid before spin_unlock_irq().

Signed-off-by: Dominic Curran <dominic.curran@
Acked-by: Daniel Stodden <daniel.stodden@citrix.com>

diff -r d971c4c2e309 drivers/xen/blktap2/device.c
--- a/drivers/xen/blktap2/device.c    Tue Mar 08 10:02:58 2011 -0800
+++ b/drivers/xen/blktap2/device.c    Tue Mar 08 10:04:28 2011 -0800
@@ -135,9 +135,11 @@
 static inline void
 blktap_end_rq(struct request *rq, int err)
 {
-    spin_lock_irq(rq->q->queue_lock);
+    struct request_queue *q = rq->q;
+
+    spin_lock_irq(q->queue_lock);
     __blktap_end_rq(rq, err);
-    spin_unlock_irq(rq->q->queue_lock);
+    spin_unlock_irq(q->queue_lock);
 }
 
 void

Re: blktap: fix reference to freed struct request.

[Daniel Stodden]

On Tue, 2011-03-08 at 13:18 -0500, Dominic Curran wrote:
> blktap: fix reference to freed struct request.
> 
> The request will be freed by the call to __blktap_end_rq(), so to
> rq->q is invalid before spin_unlock_irq().
> 
> Signed-off-by: Dominic Curran <dominic.curran@

... citrix.com>

My fault, I wasn't sure about the uk mx names anymore.

Sorry,
Daniel

> Acked-by: Daniel Stodden <daniel.stodden@citrix.com>
> 
> diff -r d971c4c2e309 drivers/xen/blktap2/device.c
> --- a/drivers/xen/blktap2/device.c    Tue Mar 08 10:02:58 2011 -0800
> +++ b/drivers/xen/blktap2/device.c    Tue Mar 08 10:04:28 2011 -0800
> @@ -135,9 +135,11 @@
>  static inline void
>  blktap_end_rq(struct request *rq, int err)
>  {
> -    spin_lock_irq(rq->q->queue_lock);
> +    struct request_queue *q = rq->q;
> +
> +    spin_lock_irq(q->queue_lock);
>      __blktap_end_rq(rq, err);
> -    spin_unlock_irq(rq->q->queue_lock);
> +    spin_unlock_irq(q->queue_lock);
>  }
>  
>  void
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

Re: blktap: fix reference to freed struct request.

[Keir Fraser]

On 08/03/2011 18:18, "Dominic Curran" <dominic.curran@citrix.com> wrote:

> blktap: fix reference to freed struct request.
> 
> The request will be freed by the call to __blktap_end_rq(), so to
> rq->q is invalid before spin_unlock_irq().

What tree is this for? Otherwise this could get dropped on the floor. If
it's for 2.6.18, the only tree that I'm still responsible for, then it needs
2.6.18 mentioned in the subject line.

 -- Keir

> Signed-off-by: Dominic Curran <dominic.curran@
> Acked-by: Daniel Stodden <daniel.stodden@citrix.com>
> 
> diff -r d971c4c2e309 drivers/xen/blktap2/device.c
> --- a/drivers/xen/blktap2/device.c    Tue Mar 08 10:02:58 2011 -0800
> +++ b/drivers/xen/blktap2/device.c    Tue Mar 08 10:04:28 2011 -0800
> @@ -135,9 +135,11 @@
>  static inline void
>  blktap_end_rq(struct request *rq, int err)
>  {
> -    spin_lock_irq(rq->q->queue_lock);
> +    struct request_queue *q = rq->q;
> +
> +    spin_lock_irq(q->queue_lock);
>      __blktap_end_rq(rq, err);
> -    spin_unlock_irq(rq->q->queue_lock);
> +    spin_unlock_irq(q->queue_lock);
>  }
>  
>  void
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

Re: blktap: fix reference to freed struct request.

[Daniel Stodden]

On Tue, 2011-03-08 at 13:57 -0500, Keir Fraser wrote:
> On 08/03/2011 18:18, "Dominic Curran" <dominic.curran@citrix.com> wrote:
> 
> > blktap: fix reference to freed struct request.
> > 
> > The request will be freed by the call to __blktap_end_rq(), so to
> > rq->q is invalid before spin_unlock_irq().
> 
> What tree is this for? Otherwise this could get dropped on the floor. If
> it's for 2.6.18, the only tree that I'm still responsible for, then it needs
> 2.6.18 mentioned in the subject line.

This should go into the pvops tree (but will need some path fixup) and
ideally goes into stable branch(es?) straight away. 2.6.18 won't have
that particular bug, unless that code was patched in.

Daniel

>  -- Keir
> 
> > Signed-off-by: Dominic Curran <dominic.curran@
> > Acked-by: Daniel Stodden <daniel.stodden@citrix.com>
> > 
> > diff -r d971c4c2e309 drivers/xen/blktap2/device.c
> > --- a/drivers/xen/blktap2/device.c    Tue Mar 08 10:02:58 2011 -0800
> > +++ b/drivers/xen/blktap2/device.c    Tue Mar 08 10:04:28 2011 -0800
> > @@ -135,9 +135,11 @@
> >  static inline void
> >  blktap_end_rq(struct request *rq, int err)
> >  {
> > -    spin_lock_irq(rq->q->queue_lock);
> > +    struct request_queue *q = rq->q;
> > +
> > +    spin_lock_irq(q->queue_lock);
> >      __blktap_end_rq(rq, err);
> > -    spin_unlock_irq(rq->q->queue_lock);
> > +    spin_unlock_irq(q->queue_lock);
> >  }
> >  
> >  void
> > 
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@lists.xensource.com
> > http://lists.xensource.com/xen-devel
> 
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel