Re: [Qemu-devel] [PATCH for-2.8 v3] xen_disk: split discard input to match internal representation

[Stefano Stabellini]

On Wed, 23 Nov 2016, Kevin Wolf wrote:
> Am 23.11.2016 um 12:40 hat Eric Blake geschrieben:
> > On 11/23/2016 04:39 AM, Olaf Hering wrote:
> > > The guest sends discard requests as u64 sector/count pairs, but the
> > > block layer operates internally with s64/s32 pairs. The conversion
> > > leads to IO errors in the guest, the discard request is not processed.
> > > 
> > >   domU.cfg:
> > >   'vdev=xvda, format=qcow2, backendtype=qdisk, target=/x.qcow2'
> > >   domU:
> > >   mkfs.ext4 -F /dev/xvda
> > >   Discarding device blocks: failed - Input/output error
> > > 
> > > Fix this by splitting the request into chunks of BDRV_REQUEST_MAX_SECTORS.
> > > Add input range checking to avoid overflow.
> > > 
> > > Fixes f313520 ("xen_disk: add discard support")
> > > 
> > > Signed-off-by: Olaf Hering <address@hidden>
> > > ---
> > 
> > Qualifies as a bug fix, so requesting 2.8 inclusion.
> > Reviewed-by: Eric Blake <address@hidden>
> 
> Stefano, are you going to merge this or should I take a look?

I can merge it.

Cheers,

Stefano