kernel/drivers/net/virtio_net.c, branch linux-6.9.y

virtio_net: fixing XDP for fully checksummed packets handling

2024-06-27T11:52:22Z

[ Upstream commit 703eec1b242276f2d97d98f04790ddad319ddde4 ] The XDP program can't correctly handle partially checksummed packets, but works fine with fully checksummed packets. If the device has already validated fully checksummed packets, then the driver doesn't need to re-validate them, saving CPU resources. Additionally, the driver does not drop all partially checksummed packets when VIRTIO_NET_F_GUEST_CSUM is not negotiated. This is not a bug, as the driver has always done this. Fixes: 436c9453a1ac ("virtio-net: keep vnet header zeroed after processing XDP") Signed-off-by: Heng Qi Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

virtio_net: checksum offloading handling fix

2024-06-27T11:52:22Z

[ Upstream commit 604141c036e1b636e2a71cf6e1aa09d1e45f40c2 ] In virtio spec 0.95, VIRTIO_NET_F_GUEST_CSUM was designed to handle partially checksummed packets, and the validation of fully checksummed packets by the device is independent of VIRTIO_NET_F_GUEST_CSUM negotiation. However, the specification erroneously stated: "If VIRTIO_NET_F_GUEST_CSUM is not negotiated, the device MUST set flags to zero and SHOULD supply a fully checksummed packet to the driver." This statement is inaccurate because even without VIRTIO_NET_F_GUEST_CSUM negotiation, the device can still set the VIRTIO_NET_HDR_F_DATA_VALID flag. Essentially, the device can facilitate the validation of these packets' checksums - a process known as RX checksum offloading - removing the need for the driver to do so. This scenario is currently not implemented in the driver and requires correction. The necessary specification correction[1] has been made and approved in the virtio TC vote. [1] https://lists.oasis-open.org/archives/virtio-comment/202401/msg00011.html Fixes: 4f49129be6fa ("virtio-net: Set RXCSUM feature if GUEST_CSUM is available") Signed-off-by: Heng Qi Reviewed-by: Jiri Pirko Acked-by: Jason Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

virtio_net: fix possible dim status unrecoverable

2024-06-21T12:40:03Z

[ Upstream commit 9e0945b1901c9eed4fbee3b8a3870487b2bdc936 ] When the dim worker is scheduled, if it no longer needs to issue commands, dim may not be able to return to the working state later. For example, the following single queue scenario: 1. The dim worker of rxq0 is scheduled, and the dim status is changed to DIM_APPLY_NEW_PROFILE; 2. dim is disabled or parameters have not been modified; 3. virtnet_rx_dim_work exits directly; Then, even if net_dim is invoked again, it cannot work because the state is not restored to DIM_START_MEASURE. Fixes: 6208799553a8 ("virtio-net: support rx netdim") Signed-off-by: Heng Qi Reviewed-by: Jiri Pirko Acked-by: Michael S. Tsirkin Reviewed-by: Xuan Zhuo Link: https://lore.kernel.org/r/20240528134116.117426-2-hengqi@linux.alibaba.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

virtio_net: Do not send RSS key if it is not supported

2024-04-07T14:43:14Z

There is a bug when setting the RSS options in virtio_net that can break the whole machine, getting the kernel into an infinite loop. Running the following command in any QEMU virtual machine with virtionet will reproduce this problem: # ethtool -X eth0 hfunc toeplitz This is how the problem happens: 1) ethtool_set_rxfh() calls virtnet_set_rxfh() 2) virtnet_set_rxfh() calls virtnet_commit_rss_command() 3) virtnet_commit_rss_command() populates 4 entries for the rss scatter-gather 4) Since the command above does not have a key, then the last scatter-gatter entry will be zeroed, since rss_key_size == 0. sg_buf_size = vi->rss_key_size; 5) This buffer is passed to qemu, but qemu is not happy with a buffer with zero length, and do the following in virtqueue_map_desc() (QEMU function): if (!sz) { virtio_error(vdev, "virtio: zero sized buffers are not allowed"); 6) virtio_error() (also QEMU function) set the device as broken vdev->broken = true; 7) Qemu bails out, and do not repond this crazy kernel. 8) The kernel is waiting for the response to come back (function virtnet_send_command()) 9) The kernel is waiting doing the following : while (!virtqueue_get_buf(vi->cvq, &tmp) && !virtqueue_is_broken(vi->cvq)) cpu_relax(); 10) None of the following functions above is true, thus, the kernel loops here forever. Keeping in mind that virtqueue_is_broken() does not look at the qemu `vdev->broken`, so, it never realizes that the vitio is broken at QEMU side. Fix it by not sending RSS commands if the feature is not available in the device. Fixes: c7114b1249fa ("drivers/net/virtio_net: Added basic RSS support.") Cc: stable@vger.kernel.org Cc: qemu-devel@nongnu.org Signed-off-by: Breno Leitao Reviewed-by: Heng Qi Reviewed-by: Xuan Zhuo Signed-off-by: David S. Miller

virtio_net: rename free_old_xmit_skbs to free_old_xmit

2024-03-19T07:19:22Z

Since free_old_xmit_skbs not only deals with skb, but also xdp frame and subsequent added xsk, so change the name of this function to free_old_xmit. Signed-off-by: Xuan Zhuo Acked-by: Jason Wang Message-Id: <20240229072044.77388-19-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin

virtio_net: unify the code for recycling the xmit ptr

2024-03-19T07:19:22Z

There are two completely similar and independent implementations. This is inconvenient for the subsequent addition of new types. So extract a function from this piece of code and call this function uniformly to recover old xmit ptr. Signed-off-by: Xuan Zhuo Acked-by: Jason Wang Message-Id: <20240229072044.77388-18-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin

virtio-net: add cond_resched() to the command waiting loop

2024-03-19T07:19:22Z

Adding cond_resched() to the command waiting loop for a better co-operation with the scheduler. This allows to give CPU a breath to run other task(workqueue) instead of busy looping when preemption is not allowed on a device whose CVQ might be slow. Signed-off-by: Jason Wang Message-Id: <20230720083839.481487-3-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Shannon Nelson

virtio-net: convert rx mode setting to use workqueue

2024-03-19T07:19:22Z

This patch convert rx mode setting to be done in a workqueue, this is a must for allow to sleep when waiting for the cvq command to response since current code is executed under addr spin lock. Note that we need to disable and flush the workqueue during freeze, this means the rx mode setting is lost after resuming. This is not the bug of this patch as we never try to restore rx mode setting during resume. Signed-off-by: Jason Wang Message-Id: <20230720083839.481487-2-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Shannon Nelson

virtio_net: Fix "‘%d’ directive writing between 1 and 11 bytes into a region of size 10" warnings

2024-01-12T00:54:34Z

Fix the warnings when building virtio_net driver. " drivers/net/virtio_net.c: In function ‘init_vqs’: drivers/net/virtio_net.c:4551:48: warning: ‘%d’ directive writing between 1 and 11 bytes into a region of size 10 [-Wformat-overflow=] 4551 | sprintf(vi->rq[i].name, "input.%d", i); | ^~ In function ‘virtnet_find_vqs’, inlined from ‘init_vqs’ at drivers/net/virtio_net.c:4645:8: drivers/net/virtio_net.c:4551:41: note: directive argument in the range [-2147483643, 65534] 4551 | sprintf(vi->rq[i].name, "input.%d", i); | ^~~~~~~~~~ drivers/net/virtio_net.c:4551:17: note: ‘sprintf’ output between 8 and 18 bytes into a destination of size 16 4551 | sprintf(vi->rq[i].name, "input.%d", i); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/virtio_net.c: In function ‘init_vqs’: drivers/net/virtio_net.c:4552:49: warning: ‘%d’ directive writing between 1 and 11 bytes into a region of size 9 [-Wformat-overflow=] 4552 | sprintf(vi->sq[i].name, "output.%d", i); | ^~ In function ‘virtnet_find_vqs’, inlined from ‘init_vqs’ at drivers/net/virtio_net.c:4645:8: drivers/net/virtio_net.c:4552:41: note: directive argument in the range [-2147483643, 65534] 4552 | sprintf(vi->sq[i].name, "output.%d", i); | ^~~~~~~~~~~ drivers/net/virtio_net.c:4552:17: note: ‘sprintf’ output between 9 and 19 bytes into a destination of size 16 4552 | sprintf(vi->sq[i].name, "output.%d", i); " Reviewed-by: Xuan Zhuo Signed-off-by: Zhu Yanjun Link: https://lore.kernel.org/r/20240104020902.2753599-1-yanjun.zhu@intel.com Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2024-01-05T02:06:46Z

Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt.c e009b2efb7a8 ("bnxt_en: Remove mis-applied code from bnxt_cfg_ntp_filters()") 0f2b21477988 ("bnxt_en: Fix compile error without CONFIG_RFS_ACCEL") https://lore.kernel.org/all/20240105115509.225aa8a2@canb.auug.org.au/ Signed-off-by: Jakub Kicinski