On Thu, Oct 05, 2017 at 08:03:35PM +0200, Alexandre DERUMIER wrote: > Hi, > > has somebody reviewed this patch ? > > I'm also able de reproduce the vm crash like the proxmox user. > This patch is fixing it for me too.
This patch should go through Michael Tsirkin's tree. I have pinged him separately in case this email thread got buried in his inbox. Stefan > > Regards, > > Alexandre > > > ----- Mail original ----- > De: "Wolfgang Bumiller" <w.bumil...@proxmox.com> > À: "qemu-devel" <qemu-devel@nongnu.org> > Cc: "pbonzini" <pbonz...@redhat.com>, "Michael S. Tsirkin" <m...@redhat.com> > Envoyé: Mercredi 20 Septembre 2017 08:09:33 > Objet: [Qemu-devel] [PATCH] virtio: fix descriptor counting in virtqueue_pop > > While changing the s/g list allocation, commit 3b3b0628 > also changed the descriptor counting to count iovec entries > as split by cpu_physical_memory_map(). Previously only the > actual descriptor entries were counted and the split into > the iovec happened afterwards in virtqueue_map(). > Count the entries again instead to avoid erroneous > "Looped descriptor" errors. > > Reported-by: Hans Middelhoek <h.middelh...@ospito.nl> > Link: https://forum.proxmox.com/threads/vm-crash-with-memory-hotplug.35904/ > Fixes: 3b3b0628217e ("virtio: slim down allocation of VirtQueueElements") > Signed-off-by: Wolfgang Bumiller <w.bumil...@proxmox.com> > --- > hw/virtio/virtio.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 890b4d7eb7..33bb770177 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -834,7 +834,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) > int64_t len; > VirtIODevice *vdev = vq->vdev; > VirtQueueElement *elem = NULL; > - unsigned out_num, in_num; > + unsigned out_num, in_num, elem_entries; > hwaddr addr[VIRTQUEUE_MAX_SIZE]; > struct iovec iov[VIRTQUEUE_MAX_SIZE]; > VRingDesc desc; > @@ -852,7 +852,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) > smp_rmb(); > > /* When we start there are none of either input nor output. */ > - out_num = in_num = 0; > + out_num = in_num = elem_entries = 0; > > max = vq->vring.num; > > @@ -922,7 +922,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) > } > > /* If we've got too many, that implies a descriptor loop. */ > - if ((in_num + out_num) > max) { > + if (++elem_entries > max) { > virtio_error(vdev, "Looped descriptor"); > goto err_undo_map; > } > -- > 2.11.0 > >
signature.asc
Description: PGP signature