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From:   Cornelia Huck <cohuck@redhat.com>
To:     Halil Pasic <pasic@linux.ibm.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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Organization: Red Hat GmbH
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Date:   Mon, 04 Oct 2021 11:51:28 +0200
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On Mon, Oct 04 2021, Halil Pasic <pasic@linux.ibm.com> wrote:

> 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.

Ok, I'll assume that you (IBM) will be able to verify that any fixup
will continue to work there.