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From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <1f3243df-1037-235f-838f-4651df476ee3@redhat.com>
Date: Fri, 22 Feb 2019 17:39:21 +0100
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Subject: Re: [Qemu-devel] [Qemu-block] Guest unresponsive after Virtqueue
 size exceeded error
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To: "Dr. David Alan Gilbert" <dgilbert@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>
Cc: =?UTF-8?Q?Fernando_Casas_Sch=c3=b6ssow?= <casasfernando@outlook.com>, Richard Henderson <rth@twiddle.net>, qemu-devel <qemu-devel@nongnu.org>, Natanael Copa <ncopa@alpinelinux.org>

On 22/02/19 17:37, Dr. David Alan Gilbert wrote:
> Why does vring_avail_idx use virtio_ld*u*w_phys_cached?
> (similar for vring_avail_ring).
> There's no generically safe way to do unaligned atomic loads - don't we know
> in virtio that these are naturally aligned?

u is for unsigned. :)  We know that these are aligned and so they will
be atomic.

Paolo