From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: miscalculated vring size in virtio-0.9.5.pdf?
Date: Wed, 19 Sep 2012 15:12:43 +0930
Message-ID: <87a9wmpnzg.fsf@rustcorp.com.au>
References: <5058EC85.5080402@redhat.com>
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To: Laszlo Ersek <lersek@redhat.com>, virtualization@lists.linux-foundation.org
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Laszlo Ersek <lersek@redhat.com> writes:
> Hi,
>
> the vring_size() formula in section 2.3 seems to miss
>
> (a) "vring_avail.used_event" in the first ALIGN(), and
>
> (b) "vring_used.flags", "vring_used.idx", "vring_used.avail_event" in
> the second ALIGN().
>
> vring_size() in Appendix A fixes (b) (no rounding up to page size
> though), but (a) is wrong there too, I believe.

Hi Laszlo,

        The effect is the same, due to ALIGN().  However, the latest
copy of the spec on github should be consistent.  Indeed, I cleaned up
the header in the Appendix so it actually compiles...

Cheers,
Rusty.