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Date:   Mon, 4 Oct 2021 11:25:28 +0200
From:   Halil Pasic <pasic@linux.ibm.com>
To:     Cornelia Huck <cohuck@redhat.com>
Cc:     "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        Xie Yongji <xieyongji@bytedance.com>,
        virtualization@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org, markver@us.ibm.com,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        linux-s390@vger.kernel.org, Halil Pasic <pasic@linux.ibm.com>
Subject: Re: [RFC PATCH 1/1] virtio: write back features before verify
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On Mon, 04 Oct 2021 09:01:42 +0200
Cornelia Huck <cohuck@redhat.com> wrote:

> On Sat, Oct 02 2021, "Michael S. Tsirkin" <mst@redhat.com> wrote:
> 
> > On Fri, Oct 01, 2021 at 05:18:46PM +0200, Cornelia Huck wrote:  
> >> I'd say we need a hack here so that we assume little-endian config space
> >> if VERSION_1 has been offered; if your patch here works, I assume QEMU
> >> does what we expect (assmuming little-endian as well.) I'm mostly
> >> wondering what happens if you use a different VMM; can we expect it to
> >> work similar to QEMU?  
> >
> > Hard to say of course ... hopefully other VMMs are actually
> > implementing the spec. E.g. IIUC rust vmm is modern only.  
> 
> Yes, I kind of hope they are simply doing LE config space accesses.
> 
> Are there any other VMMs that are actually supported on s390x (or other
> BE architectures)?
> 

I think zCX (z/OS Container Extensions) is relevant as it uses virtio.
That is all I know about.

Regards,
Halil