Re: [PATCH v3] hw/audio/virtio-snd: Use device endianness instead of target one

[Manos Pitsidianakis <manos.pitsidianakis@linaro.org>]

On Tue, 23 Apr 2024 at 11:47, Manos Pitsidianakis
<manos.pitsidianakis@linaro.org> wrote:
>
> On Tue, 23 Apr 2024 at 00:11, Michael S. Tsirkin <mst@redhat.com> wrote:
> >
> > On Mon, Apr 22, 2024 at 11:07:21PM +0200, Philippe Mathieu-Daudé wrote:
> > > On 22/4/24 23:02, Michael S. Tsirkin wrote:
> > > > On Mon, Apr 22, 2024 at 04:20:56PM +0200, Philippe Mathieu-Daudé wrote:
> > > > > Since VirtIO devices can change endianness at runtime,
> > > > > we need to use the device endianness, not the target
> > > > > one.
> > > > >
> > > > > Cc: qemu-stable@nongnu.org
> > > > > Fixes: eb9ad377bb ("virtio-sound: handle control messages and streams")
> > > > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> > > >
> > > >
> > > >
> > > > This is all completely bogus. Virtio SND is from Virtio 1.0 only.
> > > > It is unconditionally little endian.
>
>
> This part of the code is for PCM frames (raw bytes), not virtio spec
> fields (which indeed must be LE in modern VIRTIO).

Thought a little more about it. We should keep the target's endianness
here, if it's mutable then we should query the machine the device is
attached to somehow. the virtio device should never change endianness
like Michael says since it's not legacy.