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From:   Cornelia Huck <cohuck@redhat.com>
To:     Halil Pasic <pasic@linux.ibm.com>
Cc:     "Michael S. Tsirkin" <mst@redhat.com>, linux-s390@vger.kernel.org,
        markver@us.ibm.com, Christian Borntraeger <borntraeger@de.ibm.com>,
        qemu-devel@nongnu.org, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        Xie Yongji <xieyongji@bytedance.com>, stefanha@redhat.com,
        Raphael Norwitz <raphael.norwitz@nutanix.com>,
        Halil Pasic <pasic@linux.ibm.com>
Subject: Re: [RFC PATCH 1/1] virtio: write back features before verify
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Date:   Tue, 05 Oct 2021 17:25:32 +0200
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On Tue, Oct 05 2021, Halil Pasic <pasic@linux.ibm.com> wrote:

> On Tue, 05 Oct 2021 13:13:31 +0200
> Cornelia Huck <cohuck@redhat.com> wrote:
>> Or am I misunderstanding what you're getting at?
>> 
>
> Probably. I'm talking about pre- "do transport specific legacy detection
> in the device instead of looking at VERSION_1" you are probably talking
> about the post-state. If we had this new behavior for all relevant
> hypervisors then we wouldn't need to do a thing in the guest. The current
> code would work like charm.

Yeah, I was thinking more about the desired state. We need to both fix
QEMU (and other VMMs or devices should check whether they are doing the
right thing) and add a workaround on the driver side to make it work
with existing QEMUs.