From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH] virtio_rpmsg: set DRIVER_OK before using device
Date: Thu, 12 Mar 2015 11:35:49 +1030
Message-ID: <877funxbwy.fsf@rustcorp.com.au>
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To: Ohad Ben-Cohen <ohad@wizery.com>, "Michael S. Tsirkin" <mst@redhat.com>
Cc: qemu-devel@nongnu.org, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "kvm@vger.kernel.org" <kvm@vger.kernel.org>, virtualization <virtualization@lists.linux-foundation.org>
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Ohad Ben-Cohen <ohad@wizery.com> writes:
> On Mon, Mar 9, 2015 at 10:41 AM, Michael S. Tsirkin <mst@redhat.com> wrote:
>> On Sat, Mar 07, 2015 at 08:06:56PM +0100, Michael S. Tsirkin wrote:
>>> virtio spec requires that all drivers set DRIVER_OK
>>> before using devices. While rpmsg isn't yet
>>> included in the virtio 1 spec, previous spec versions
>>> also required this.
>>>
>>> virtio rpmsg violates this rule: is calls kick
>>> before setting DRIVER_OK.
>>>
>>> The fix isn't trivial since simply calling virtio_device_ready earlier
>>> would mean we might get an interrupt in parallel with adding buffers.
>>>
>>> Instead, split kick out to prepare+notify calls.  prepare before
>>> virtio_device_ready - when we know we won't get interrupts. notify right
>>> afterwards.
>>>
>>> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
>>> ---
>>
>> Ohad, can you review and ack pls?
>
> Sure,
>
> Acked-by: Ohad Ben-Cohen <ohad@wizery.com>

Applied.

Thanks,
Rusty.