similar to: [PATCH RFC] virtio_net: fix mergeable bufs error handling

On xdp error we try to free head_skb without having initialized it, that's clearly bogus. Fixes: f600b6905015 ("virtio_net: Add XDP support") Cc: John Fastabend <john.fastabend at gmail.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/virtio_net.c

On xdp error we try to free head_skb without having initialized it, that's clearly bogus. Fixes: f600b6905015 ("virtio_net: Add XDP support") Cc: John Fastabend <john.fastabend at gmail.com> Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/virtio_net.c

The purpose of this patch is to simplify the receive_mergeable(). Separate all the logic of XDP into a function. Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> --- drivers/net/virtio_net.c | 128 +++++++++++++++++++++++---------------- 1 file changed, 76 insertions(+), 52 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index

Hi, On Tue, 2023-03-28 at 20:04 +0800, Xuan Zhuo wrote: > The purpose of this patch is to simplify the receive_mergeable(). > Separate all the logic of XDP into a function. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/net/virtio_net.c | 128 +++++++++++++++++++++++---------------- > 1 file changed, 76 insertions(+), 52 deletions(-) >

XDP_REDIRECT support for mergeable buffer was removed since commit 7324f5399b06 ("virtio_net: disable XDP_REDIRECT in receive_mergeable() case"). This is because we don't reserve enough tailroom for struct skb_shared_info which breaks XDP assumption. Other complaints are, the complex linearize logic and EWMA estimation may increase the possibility of linearizing. Signed-off-by:

The virtio-net driver currently uses netdev_alloc_frag() for GFP_ATOMIC mergeable rx buffer allocations. This commit migrates virtio-net to use per-receive queue page frags for GFP_ATOMIC allocation. This change unifies mergeable rx buffer memory allocation, which now will use skb_refill_frag() for both atomic and GFP-WAIT buffer allocations. To address fragmentation concerns, if after buffer

On Thu, Mar 01, 2018 at 11:19:04AM +0800, Jason Wang wrote: > XDP_REDIRECT support for mergeable buffer was removed since commit > 7324f5399b06 ("virtio_net: disable XDP_REDIRECT in receive_mergeable() > case"). This is because we don't reserve enough tailroom for struct > skb_shared_info which breaks XDP assumption. Other complaints are, the > complex linearize logic

The virtio-net driver currently uses netdev_alloc_frag() for GFP_ATOMIC mergeable rx buffer allocations. This commit migrates virtio-net to use per-receive queue page frags for GFP_ATOMIC allocation. This change unifies mergeable rx buffer memory allocation, which now will use skb_refill_frag() for both atomic and GFP-WAIT buffer allocations. To address fragmentation concerns, if after buffer

The virtio-net driver currently uses netdev_alloc_frag() for GFP_ATOMIC mergeable rx buffer allocations. This commit migrates virtio-net to use per-receive queue page frags for GFP_ATOMIC allocation. This change unifies mergeable rx buffer memory allocation, which now will use skb_refill_frag() for both atomic and GFP-WAIT buffer allocations. To address fragmentation concerns, if after buffer

We copy vnet header unconditionally in page_to_skb() this is wrong since XDP may modify the packet data. So let's keep a zeroed vnet header for not confusing the conversion between vnet header and skb metadata. In the future, we should able to detect whether or not the packet was modified and keep using the vnet header when packet was not touched. Fixes: f600b6905015 ("virtio_net: Add

We used to reset during XDP set, the main reason is we need allocate extra headroom for header adjustment but there's no way to know the headroom of exist receive buffer. This works buy maybe complex and may cause the network down for a while which is bad for user experience. So this patch tries to avoid this by: - packing headroom into receive buffer ctx - check the headroom during XDP, and

This patch tries to add XDP_REDIRECT for virtio-net. The changes are not complex as we could use exist XDP_TX helpers for most of the work. The rest is passing the XDP_TX to NAPI handler for implementing batching. Cc: John Fastabend <john.fastabend at gmail.com> Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/net/virtio_net. | 0 drivers/net/virtio_net.c | 77

On 12/17/2013 08:16 AM, Michael Dalton wrote: > The virtio-net driver currently uses netdev_alloc_frag() for GFP_ATOMIC > mergeable rx buffer allocations. This commit migrates virtio-net to use > per-receive queue page frags for GFP_ATOMIC allocation. This change unifies > mergeable rx buffer memory allocation, which now will use skb_refill_frag() > for both atomic and GFP-WAIT

On 12/17/2013 08:16 AM, Michael Dalton wrote: > The virtio-net driver currently uses netdev_alloc_frag() for GFP_ATOMIC > mergeable rx buffer allocations. This commit migrates virtio-net to use > per-receive queue page frags for GFP_ATOMIC allocation. This change unifies > mergeable rx buffer memory allocation, which now will use skb_refill_frag() > for both atomic and GFP-WAIT

virtnet_build_xdp_buff_mrg() and virtnet_xdp_handler() auto release xdp shinfo then the caller no need to careful the xdp shinfo. Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> --- drivers/net/virtio_net.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index

? 2023/3/28 20:04, Xuan Zhuo ??: > virtnet_build_xdp_buff_mrg() and virtnet_xdp_handler() auto I think you meant virtnet_xdp_handler() actually? > release xdp shinfo then the caller no need to careful the xdp shinfo. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/net/virtio_net.c | 29 +++++++++++++++++------------ > 1 file changed,

Commit f600b6905015 ("virtio_net: Add XDP support") leaves the case of small receive buffer untouched. This will confuse the user who want to set XDP but use small buffers. Other than forbid XDP in small buffer mode, let's make it work. XDP then can only work at skb->data since virtio-net create skbs during refill, this is sub optimal which could be optimized in the future. Cc:

Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers

On Wed, Nov 13, 2013 at 03:10:20PM +0800, Jason Wang wrote: > On 11/13/2013 06:21 AM, Michael Dalton wrote: > > Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag > > allocators") changed the mergeable receive buffer size from PAGE_SIZE to > > MTU-size, introducing a single-stream regression for benchmarks with large > > average packet

On 11/28/2013 12:31 AM, Michael S. Tsirkin wrote: > Eric Dumazet noticed that if we encounter an error > when processing a mergeable buffer, we don't > dequeue all of the buffers from this packet, > the result is almost sure to be loss of networking. > > Jason Wang noticed that we also leak a page and that we don't decrement > the rq buf count, so we won't repost