From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45702) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wk8Wp-0001c9-OF for qemu-devel@nongnu.org; Tue, 13 May 2014 04:57:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Wk8Wk-0003kt-MQ for qemu-devel@nongnu.org; Tue, 13 May 2014 04:57:39 -0400 Date: Tue, 13 May 2014 09:57:26 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20140513085725.GC2566@work-vm> References: <1399885648-14985-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1399885648-14985-1-git-send-email-mst@redhat.com> Subject: Re: [Qemu-devel] [PATCH] virtio: allow mapping up to max queue size List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: peter.maydell@linaro.org, qemu-stable@nongnu.org, qemu-devel@nongnu.org, stefanha@redhat.com, Anthony Liguori * Michael S. Tsirkin (mst@redhat.com) wrote: > It's a loop from i < num_sg and the array is VIRTQUEUE_MAX_SIZE - so > it's OK if the value read is VIRTQUEUE_MAX_SIZE. > > Not a big problem in practice as people don't use > such big queues, but it's inelegant. > > Reported-by: "Dr. David Alan Gilbert" > Cc: qemu-stable@nongnu.org > Signed-off-by: Michael S. Tsirkin Reviewed-by: Dr. David Alan Gilbert > --- > hw/virtio/virtio.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 7f4e7ec..3557c17 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -430,7 +430,7 @@ void virtqueue_map_sg(struct iovec *sg, hwaddr *addr, > unsigned int i; > hwaddr len; > > - if (num_sg >= VIRTQUEUE_MAX_SIZE) { > + if (num_sg > VIRTQUEUE_MAX_SIZE) { > error_report("virtio: map attempt out of bounds: %zd > %d", > num_sg, VIRTQUEUE_MAX_SIZE); > exit(1); > -- > MST > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK