On Tue, Oct 09, 2018 at 12:34:28PM +0200, Maxime Coquelin wrote: > On 10/09/2018 12:30 PM, Maxime Coquelin wrote: > > On 10/09/2018 12:21 PM, Tiwei Bie wrote: > > > On Mon, Oct 08, 2018 at 05:25:42PM +0200, Maxime Coquelin wrote: > > > > QEMU doesn't expect any payload for the reply of > > > > VHOST_USER_SET_LOG_BASE request, so don't send any. > > > > Note that the Vhost-user specification isn't clear about > > > > it and would need to be fixed. > > > > > > > > Fixes: 54f9e32305d4 ("vhost: handle dirty pages logging request") > > > > Cc: sta...@dpdk.org > > > > > > > > Reported-by: Ilya Maximets <i.maxim...@samsung.com> > > > > Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com> > > > > Acked-by: Ilya Maximets <i.maxim...@samsung.com> > > > > --- > > > > lib/librte_vhost/vhost_user.c | 6 +++++- > > > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/lib/librte_vhost/vhost_user.c > > > > b/lib/librte_vhost/vhost_user.c > > > > index 7f3e86778..71a0e7dd7 100644 > > > > --- a/lib/librte_vhost/vhost_user.c > > > > +++ b/lib/librte_vhost/vhost_user.c > > > > @@ -1296,7 +1296,11 @@ vhost_user_set_log_base(struct virtio_net > > > > **pdev, struct VhostUserMsg *msg) > > > > dev->log_base = dev->log_addr + off; > > > > dev->log_size = size; > > > > - msg->size = sizeof(msg->payload.u64); > > > > + /* > > > > + * The spec is not clear about it (yet), but QEMU doesn't expect > > > > + * any payload in the reply. > > > > + */ > > > > + msg->size = 0; > > > > > > I think the spec is clear about it that no payload is > > > expected in the reply: > > > > > > https://github.com/qemu/qemu/blob/7c69b7c84964/docs/interop/vhost-user.txt#L496 > > > > > It isn't really clear because there are two cases[0]: > > 1. VHOST_USER_PROTOCOL_F_LOG_SHMFD not negotiated: In this case no reply > > has to be sent. > > 2. VHOST_USER_PROTOCOL_F_LOG_SHMFD negotiated: In this case reply with > > empty payload hsa to be sent. > > > > [0]: > > https://github.com/qemu/qemu/blob/7c69b7c849641a39ba3defa40d384a2ba24cd7a2/docs/interop/vhost-user.txt#L177 > > > > And I would add that N/A isn't clear, because SET_VRING_ADDR specifies > N/A as slave payload, whereas the implementation does not implement a > reply.
Good point. > > > > But below line in the spec needs to be fixed: > > > > > > https://github.com/qemu/qemu/blob/7c69b7c84964/docs/interop/vhost-user.txt#L495 > > > > > > > Indeed. > > > > > > > > > return VH_RESULT_REPLY; > > > > } > > > > -- > > > > 2.17.1 > > > >