In virtio 1.0 mode, when mergeable buffers are enabled on a big-endian host, num_buffers wasn't byte-swapped correctly, so large incoming packets got corrupted. To fix, fill it in within hdr - this also makes sure it gets the correct type. Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> --- It seems important to get this into 3.19, otherwise VIRTIO_1 feature bit is unreliable. Dave, do you plan another pull request for 3.19? If yes pls merge this, if not pls let me know and I'll try to send it to Linus directly. drivers/vhost/net.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index d415d69..9484d56 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -650,8 +650,10 @@ static void handle_rx(struct vhost_net *net) break; } /* TODO: Should check and handle checksum. */ + + hdr.num_buffers = cpu_to_vhost16(vq, headcount); if (likely(mergeable) && - memcpy_toiovecend(nvq->hdr, (unsigned char *)&headcount, + memcpy_toiovecend(nvq->hdr, (void *)&hdr.num_buffers, offsetof(typeof(hdr), num_buffers), sizeof hdr.num_buffers)) { vq_err(vq, "Failed num_buffers write"); -- MST _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization