Re: [Qemu-devel] [PATCH v3 0/2] virtio: fix IO request length in virtio SCSI/block

[Michael S. Tsirkin]

On Fri, Dec 15, 2017 at 06:02:48PM +0300, Denis V. Lunev wrote:
> v2->v3
> - added 2.12 machine types
> - added compat properties for 2.11 machine type
> 
> v1->v2:
> - added max_segments property for virtblock device

I'm not applying this for now.

It seems too easy to create illegal configurations with it,
e.g. where max seg > queue size.

1022 also seems too aggressive - e.g. if a couple of segments
cross page boundaries, we'll exceed the iov length. around
500 seems more prudent.

Guerd, could you pls also take a look at whether seabios is
smart enough to downgrade if guest queue size is too big?

> Signed-off-by: Denis V. Lunev <address@hidden>
> CC: "Michael S. Tsirkin" <address@hidden>
> CC: Stefan Hajnoczi <address@hidden>
> CC: Kevin Wolf <address@hidden>
> CC: Max Reitz <address@hidden>
> CC: Paolo Bonzini <address@hidden>
> CC: Richard Henderson <address@hidden>
> CC: Eduardo Habkost <address@hidden>