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Date: Thu, 10 Nov 2011 00:17:20 +0100
From: =?ISO-8859-15?Q?Andreas_F=E4rber?= <afaerber@suse.de>
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Subject: Re: [Qemu-devel] [TestDays] s390x emulation error
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To: Alexander Graf <agraf@suse.de>
Cc: qemu-devel Developers <qemu-devel@nongnu.org>

Am 09.11.2011 23:53, schrieb Andreas F=E4rber:
> I get the following error:
>=20
> $ s390x-softmmu/qemu-system-s390x
> qemu-system-s390x: Guest moved used index from 0 to 47802

This is coming from hw/virtio.c:

static int virtqueue_num_heads(VirtQueue *vq, unsigned int idx)
{
    uint16_t num_heads =3D vring_avail_idx(vq) - idx;

    /* Check it isn't doing very strange things with descriptor numbers. =
*/
    if (num_heads > vq->vring.num) {
        error_report("Guest moved used index from %u to %u",
                     idx, vring_avail_idx(vq));
        exit(1);
    }

    return num_heads;
}

Any idea? Couldn't find a related s390-specific patch on the list.

Andreas

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