On Wed, Mar 12, 2025 at 1:59 PM Akihiko Odaki akihiko.odaki@daynix.com wrote:
On 2025/03/12 12:36, Jason Wang wrote:
On Tue, Mar 11, 2025 at 2:24 PM Akihiko Odaki akihiko.odaki@daynix.com wrote:
On 2025/03/11 9:42, Jason Wang wrote:
On Mon, Mar 10, 2025 at 3:04 PM Akihiko Odaki akihiko.odaki@daynix.com wrote:
On 2025/03/10 13:43, Jason Wang wrote:
On Fri, Mar 7, 2025 at 7:02 PM Akihiko Odaki akihiko.odaki@daynix.com wrote: > > VIRTIO_NET_F_HASH_REPORT allows to report hash values calculated on the > host. When VHOST_NET_F_VIRTIO_NET_HDR is employed, it will report no > hash values (i.e., the hash_report member is always set to > VIRTIO_NET_HASH_REPORT_NONE). Otherwise, the values reported by the > underlying socket will be reported. > > VIRTIO_NET_F_HASH_REPORT requires VIRTIO_F_VERSION_1. > > Signed-off-by: Akihiko Odaki akihiko.odaki@daynix.com > Tested-by: Lei Yang leiyang@redhat.com > --- > drivers/vhost/net.c | 49 +++++++++++++++++++++++++++++-------------------- > 1 file changed, 29 insertions(+), 20 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index b9b9e9d40951856d881d77ac74331d914473cd56..16b241b44f89820a42c302f3586ea6bb5e0d4289 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -73,6 +73,7 @@ enum { > VHOST_NET_FEATURES = VHOST_FEATURES | > (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | > (1ULL << VIRTIO_NET_F_MRG_RXBUF) | > + (1ULL << VIRTIO_NET_F_HASH_REPORT) | > (1ULL << VIRTIO_F_ACCESS_PLATFORM) | > (1ULL << VIRTIO_F_RING_RESET) > }; > @@ -1097,9 +1098,11 @@ static void handle_rx(struct vhost_net *net) > .msg_controllen = 0, > .msg_flags = MSG_DONTWAIT, > }; > - struct virtio_net_hdr hdr = { > - .flags = 0, > - .gso_type = VIRTIO_NET_HDR_GSO_NONE > + struct virtio_net_hdr_v1_hash hdr = { > + .hdr = { > + .flags = 0, > + .gso_type = VIRTIO_NET_HDR_GSO_NONE > + } > }; > size_t total_len = 0; > int err, mergeable; > @@ -1110,7 +1113,6 @@ static void handle_rx(struct vhost_net *net) > bool set_num_buffers; > struct socket *sock; > struct iov_iter fixup; > - __virtio16 num_buffers; > int recv_pkts = 0; > > mutex_lock_nested(&vq->mutex, VHOST_NET_VQ_RX); > @@ -1191,30 +1193,30 @@ static void handle_rx(struct vhost_net *net) > vhost_discard_vq_desc(vq, headcount); > continue; > } > + hdr.hdr.num_buffers = cpu_to_vhost16(vq, headcount); > /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ > if (unlikely(vhost_hlen)) { > - if (copy_to_iter(&hdr, sizeof(hdr), > - &fixup) != sizeof(hdr)) { > + if (copy_to_iter(&hdr, vhost_hlen, > + &fixup) != vhost_hlen) { > vq_err(vq, "Unable to write vnet_hdr " > "at addr %p\n", vq->iov->iov_base); > goto out;
Is this an "issue" specific to RSS/HASH? If it's not, we need a separate patch.
Honestly, I'm not sure if it's too late to fix this.
There is nothing wrong with the current implementation.
Note that I meant the vhost_hlen part, and the current code is tricky.
The comment said:
""" /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ """
So it tries to only offer virtio_net_hdr even if vhost_hlen is the set to mrg_rxbuf len.
And this patch changes this behaviour.
mrg_rxbuf only adds the num_buffers field, which is always set for mrg_rxbuf.
The num_buffers was not set for VIRTIO_F_VERSION_1 in the past, but this was also fixed with commit a3b9c053d82a ("vhost/net: Set num_buffers for virtio 1.0")
So there is no behavioral change for existing features with this patch.
I meant this part.
if (copy_to_iter(&hdr, vhost_hlen,&fixup) != vhost_hlen) {We should copy only sizeof(hdr) instead of vhost_hlen.> > Anything I miss?
sizeof(hdr) will be greater than vhost_hlen when neither VIRTIO_NET_F_MRG_RXBUF or VIRTIO_F_VERSION_1 is negotiated.
Just to make sure we are on the same page I meant we should only advance sizeof(struct virtio_net_hdr) here to make sure we can set the num_buffers correctly.
But this is not what the code did here.
Thanks
Regards, Akihiko Odaki
Thanks
Regards, Akihiko Odaki
Thanks
The current implementation fills the header with zero except num_buffers, which it fills some real value. This functionality is working fine with VIRTIO_NET_F_MRG_RXBUF and VIRTIO_F_VERSION_1, which change the header size.
Now I'm adding VIRTIO_NET_F_HASH_REPORT and it adds the hash_report field, which also needs to be initialized with zero, so I'm making sure vhost_net will also initialize it.
Regards, Akihiko Odaki
Others look fine.
Thanks