linux.git/drivers/net/veth.c, branch v6.8 Linux kernel source tree veth: try harder when allocating queue memory 2024-02-27T12:56:54+00:00 Jakub Kicinski kuba@kernel.org 2024-02-23T23:59:08+00:00 1ce7d306ea63f3e379557c79abd88052e0483813 struct veth_rq is pretty large, 832B total without debug options enabled. Since commit under Fixes we try to pre-allocate enough queues for every possible CPU. Miao Wang reports that this may lead to order-5 allocations which will fail in production. Let the allocation fallback to vmalloc() and try harder. These are the same flags we pass to netdev queue allocation. Reported-and-tested-by: Miao Wang <shankerwangmiao@gmail.com> Fixes: 9d3684c24a52 ("veth: create by default nr_possible_cpus queues") Link: https://lore.kernel.org/all/5F52CAE2-2FB7-4712-95F1-3312FBBFA8DD@gmail.com/ Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240223235908.693010-1-kuba@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
struct veth_rq is pretty large, 832B total without debug
options enabled. Since commit under Fixes we try to pre-allocate
enough queues for every possible CPU. Miao Wang reports that
this may lead to order-5 allocations which will fail in production.

Let the allocation fallback to vmalloc() and try harder.
These are the same flags we pass to netdev queue allocation.

Reported-and-tested-by: Miao Wang <shankerwangmiao@gmail.com>
Fixes: 9d3684c24a52 ("veth: create by default nr_possible_cpus queues")
Link: https://lore.kernel.org/all/5F52CAE2-2FB7-4712-95F1-3312FBBFA8DD@gmail.com/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240223235908.693010-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net: veth: clear GRO when clearing XDP even when down 2024-02-26T11:34:13+00:00 Jakub Kicinski kuba@kernel.org 2024-02-21T23:12:10+00:00 fe9f801355f0b47668419f30f1fac1cf4539e736 veth sets NETIF_F_GRO automatically when XDP is enabled, because both features use the same NAPI machinery. The logic to clear NETIF_F_GRO sits in veth_disable_xdp() which is called both on ndo_stop and when XDP is turned off. To avoid the flag from being cleared when the device is brought down, the clearing is skipped when IFF_UP is not set. Bringing the device down should indeed not modify its features. Unfortunately, this means that clearing is also skipped when XDP is disabled _while_ the device is down. And there's nothing on the open path to bring the device features back into sync. IOW if user enables XDP, disables it and then brings the device up we'll end up with a stray GRO flag set but no NAPI instances. We don't depend on the GRO flag on the datapath, so the datapath won't crash. We will crash (or hang), however, next time features are sync'ed (either by user via ethtool or peer changing its config). The GRO flag will go away, and veth will try to disable the NAPIs. But the open path never created them since XDP was off, the GRO flag was a stray. If NAPI was initialized before we'll hang in napi_disable(). If it never was we'll crash trying to stop uninitialized hrtimer. Move the GRO flag updates to the XDP enable / disable paths, instead of mixing them with the ndo_open / ndo_close paths. Fixes: d3256efd8e8b ("veth: allow enabling NAPI even without XDP") Reported-by: Thomas Gleixner <tglx@linutronix.de> Reported-by: syzbot+039399a9b96297ddedca@syzkaller.appspotmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
veth sets NETIF_F_GRO automatically when XDP is enabled,
because both features use the same NAPI machinery.

The logic to clear NETIF_F_GRO sits in veth_disable_xdp() which
is called both on ndo_stop and when XDP is turned off.
To avoid the flag from being cleared when the device is brought
down, the clearing is skipped when IFF_UP is not set.
Bringing the device down should indeed not modify its features.

Unfortunately, this means that clearing is also skipped when
XDP is disabled _while_ the device is down. And there's nothing
on the open path to bring the device features back into sync.
IOW if user enables XDP, disables it and then brings the device
up we'll end up with a stray GRO flag set but no NAPI instances.

We don't depend on the GRO flag on the datapath, so the datapath
won't crash. We will crash (or hang), however, next time features
are sync'ed (either by user via ethtool or peer changing its config).
The GRO flag will go away, and veth will try to disable the NAPIs.
But the open path never created them since XDP was off, the GRO flag
was a stray. If NAPI was initialized before we'll hang in napi_disable().
If it never was we'll crash trying to stop uninitialized hrtimer.

Move the GRO flag updates to the XDP enable / disable paths,
instead of mixing them with the ndo_open / ndo_close paths.

Fixes: d3256efd8e8b ("veth: allow enabling NAPI even without XDP")
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: syzbot+039399a9b96297ddedca@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2023-12-19T00:46:08+00:00 Jakub Kicinski kuba@kernel.org 2023-12-19T00:46:07+00:00 c49b292d031e385abf764ded32cd953c77e73f2d Alexei Starovoitov says: ==================== pull-request: bpf-next 2023-12-18 This PR is larger than usual and contains changes in various parts of the kernel. The main changes are: 1) Fix kCFI bugs in BPF, from Peter Zijlstra. End result: all forms of indirect calls from BPF into kernel and from kernel into BPF work with CFI enabled. This allows BPF to work with CONFIG_FINEIBT=y. 2) Introduce BPF token object, from Andrii Nakryiko. It adds an ability to delegate a subset of BPF features from privileged daemon (e.g., systemd) through special mount options for userns-bound BPF FS to a trusted unprivileged application. The design accommodates suggestions from Christian Brauner and Paul Moore. Example: $ sudo mkdir -p /sys/fs/bpf/token $ sudo mount -t bpf bpffs /sys/fs/bpf/token \ -o delegate_cmds=prog_load:MAP_CREATE \ -o delegate_progs=kprobe \ -o delegate_attachs=xdp 3) Various verifier improvements and fixes, from Andrii Nakryiko, Andrei Matei. - Complete precision tracking support for register spills - Fix verification of possibly-zero-sized stack accesses - Fix access to uninit stack slots - Track aligned STACK_ZERO cases as imprecise spilled registers. It improves the verifier "instructions processed" metric from single digit to 50-60% for some programs. - Fix verifier retval logic 4) Support for VLAN tag in XDP hints, from Larysa Zaremba. 5) Allocate BPF trampoline via bpf_prog_pack mechanism, from Song Liu. End result: better memory utilization and lower I$ miss for calls to BPF via BPF trampoline. 6) Fix race between BPF prog accessing inner map and parallel delete, from Hou Tao. 7) Add bpf_xdp_get_xfrm_state() kfunc, from Daniel Xu. It allows BPF interact with IPSEC infra. The intent is to support software RSS (via XDP) for the upcoming ipsec pcpu work. Experiments on AWS demonstrate single tunnel pcpu ipsec reaching line rate on 100G ENA nics. 8) Expand bpf_cgrp_storage to support cgroup1 non-attach, from Yafang Shao. 9) BPF file verification via fsverity, from Song Liu. It allows BPF progs get fsverity digest. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (164 commits) bpf: Ensure precise is reset to false in __mark_reg_const_zero() selftests/bpf: Add more uprobe multi fail tests bpf: Fail uprobe multi link with negative offset selftests/bpf: Test the release of map btf s390/bpf: Fix indirect trampoline generation selftests/bpf: Temporarily disable dummy_struct_ops test on s390 x86/cfi,bpf: Fix bpf_exception_cb() signature bpf: Fix dtor CFI cfi: Add CFI_NOSEAL() x86/cfi,bpf: Fix bpf_struct_ops CFI x86/cfi,bpf: Fix bpf_callback_t CFI x86/cfi,bpf: Fix BPF JIT call cfi: Flip headers selftests/bpf: Add test for abnormal cnt during multi-kprobe attachment selftests/bpf: Don't use libbpf_get_error() in kprobe_multi_test selftests/bpf: Add test for abnormal cnt during multi-uprobe attachment bpf: Limit the number of kprobes when attaching program to multiple kprobes bpf: Limit the number of uprobes when attaching program to multiple uprobes bpf: xdp: Register generic_kfunc_set with XDP programs selftests/bpf: utilize string values for delegate_xxx mount options ... ==================== Link: https://lore.kernel.org/r/20231219000520.34178-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Alexei Starovoitov says:

====================
pull-request: bpf-next 2023-12-18

This PR is larger than usual and contains changes in various parts
of the kernel.

The main changes are:

1) Fix kCFI bugs in BPF, from Peter Zijlstra.

End result: all forms of indirect calls from BPF into kernel
and from kernel into BPF work with CFI enabled. This allows BPF
to work with CONFIG_FINEIBT=y.

2) Introduce BPF token object, from Andrii Nakryiko.

It adds an ability to delegate a subset of BPF features from privileged
daemon (e.g., systemd) through special mount options for userns-bound
BPF FS to a trusted unprivileged application. The design accommodates
suggestions from Christian Brauner and Paul Moore.

Example:
$ sudo mkdir -p /sys/fs/bpf/token
$ sudo mount -t bpf bpffs /sys/fs/bpf/token \
             -o delegate_cmds=prog_load:MAP_CREATE \
             -o delegate_progs=kprobe \
             -o delegate_attachs=xdp

3) Various verifier improvements and fixes, from Andrii Nakryiko, Andrei Matei.

 - Complete precision tracking support for register spills
 - Fix verification of possibly-zero-sized stack accesses
 - Fix access to uninit stack slots
 - Track aligned STACK_ZERO cases as imprecise spilled registers.
   It improves the verifier "instructions processed" metric from single
   digit to 50-60% for some programs.
 - Fix verifier retval logic

4) Support for VLAN tag in XDP hints, from Larysa Zaremba.

5) Allocate BPF trampoline via bpf_prog_pack mechanism, from Song Liu.

End result: better memory utilization and lower I$ miss for calls to BPF
via BPF trampoline.

6) Fix race between BPF prog accessing inner map and parallel delete,
from Hou Tao.

7) Add bpf_xdp_get_xfrm_state() kfunc, from Daniel Xu.

It allows BPF interact with IPSEC infra. The intent is to support
software RSS (via XDP) for the upcoming ipsec pcpu work.
Experiments on AWS demonstrate single tunnel pcpu ipsec reaching
line rate on 100G ENA nics.

8) Expand bpf_cgrp_storage to support cgroup1 non-attach, from Yafang Shao.

9) BPF file verification via fsverity, from Song Liu.

It allows BPF progs get fsverity digest.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (164 commits)
  bpf: Ensure precise is reset to false in __mark_reg_const_zero()
  selftests/bpf: Add more uprobe multi fail tests
  bpf: Fail uprobe multi link with negative offset
  selftests/bpf: Test the release of map btf
  s390/bpf: Fix indirect trampoline generation
  selftests/bpf: Temporarily disable dummy_struct_ops test on s390
  x86/cfi,bpf: Fix bpf_exception_cb() signature
  bpf: Fix dtor CFI
  cfi: Add CFI_NOSEAL()
  x86/cfi,bpf: Fix bpf_struct_ops CFI
  x86/cfi,bpf: Fix bpf_callback_t CFI
  x86/cfi,bpf: Fix BPF JIT call
  cfi: Flip headers
  selftests/bpf: Add test for abnormal cnt during multi-kprobe attachment
  selftests/bpf: Don't use libbpf_get_error() in kprobe_multi_test
  selftests/bpf: Add test for abnormal cnt during multi-uprobe attachment
  bpf: Limit the number of kprobes when attaching program to multiple kprobes
  bpf: Limit the number of uprobes when attaching program to multiple uprobes
  bpf: xdp: Register generic_kfunc_set with XDP programs
  selftests/bpf: utilize string values for delegate_xxx mount options
  ...
====================

Link: https://lore.kernel.org/r/20231219000520.34178-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
veth: Implement VLAN tag XDP hint 2023-12-14T00:16:41+00:00 Larysa Zaremba larysa.zaremba@intel.com 2023-12-05T21:08:41+00:00 fca783799f64ac0a4f20228ff6a6d7598db11e64 In order to test VLAN tag hint in hardware-independent selftests, implement newly added hint in veth driver. Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com> Link: https://lore.kernel.org/r/20231205210847.28460-13-larysa.zaremba@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
In order to test VLAN tag hint in hardware-independent selftests, implement
newly added hint in veth driver.

Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Link: https://lore.kernel.org/r/20231205210847.28460-13-larysa.zaremba@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
net: veth: fix packet segmentation in veth_convert_skb_to_xdp_buff 2023-12-06T03:24:26+00:00 Lorenzo Bianconi lorenzo@kernel.org 2023-12-04T15:01:48+00:00 a61f46e1102545cf1fb5f19992288265362cefb0 Based on the previous allocated packet, page_offset can be not null in veth_convert_skb_to_xdp_buff routine. Take into account page fragment offset during the skb paged area copy in veth_convert_skb_to_xdp_buff(). Fixes: 2d0de67da51a ("net: veth: use newly added page pool API for veth with xdp") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Link: https://lore.kernel.org/r/eddfe549e7e626870071930964ac3c38a1dc8068.1701702000.git.lorenzo@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Based on the previous allocated packet, page_offset can be not null
in veth_convert_skb_to_xdp_buff routine.
Take into account page fragment offset during the skb paged area copy
in veth_convert_skb_to_xdp_buff().

Fixes: 2d0de67da51a ("net: veth: use newly added page pool API for veth with xdp")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
Link: https://lore.kernel.org/r/eddfe549e7e626870071930964ac3c38a1dc8068.1701702000.git.lorenzo@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: veth: fix ethtool stats reporting 2023-11-23T12:23:59+00:00 Lorenzo Bianconi lorenzo@kernel.org 2023-11-21T19:08:44+00:00 818ad9cc90d4a7165caaee7e32800c50d0564ec3 Fix a possible misalignment between page_pool stats and tx xdp_stats reported in veth_get_ethtool_stats routine. The issue can be reproduced configuring the veth pair with the following tx/rx queues: $ip link add v0 numtxqueues 2 numrxqueues 4 type veth peer name v1 \ numtxqueues 1 numrxqueues 1 and loading a simple XDP program on v0 that just returns XDP_PASS. In this case on v0 the page_pool stats overwrites tx xdp_stats for queue 1. Fix the issue incrementing pp_idx of dev->real_num_tx_queues * VETH_TQ_STATS_LEN since we always report xdp_stats for all tx queues in ethtool. Fixes: 4fc418053ec7 ("net: veth: add page_pool stats") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/r/c5b5d0485016836448453f12846c7c4ab75b094a.1700593593.git.lorenzo@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Fix a possible misalignment between page_pool stats and tx xdp_stats
reported in veth_get_ethtool_stats routine.
The issue can be reproduced configuring the veth pair with the
following tx/rx queues:

$ip link add v0 numtxqueues 2 numrxqueues 4 type veth peer name v1 \
 numtxqueues 1 numrxqueues 1

and loading a simple XDP program on v0 that just returns XDP_PASS.
In this case on v0 the page_pool stats overwrites tx xdp_stats for queue 1.
Fix the issue incrementing pp_idx of dev->real_num_tx_queues * VETH_TQ_STATS_LEN
since we always report xdp_stats for all tx queues in ethtool.

Fixes: 4fc418053ec7 ("net: veth: add page_pool stats")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/c5b5d0485016836448453f12846c7c4ab75b094a.1700593593.git.lorenzo@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
veth: Use tstats per-CPU traffic counters 2023-11-20T18:15:16+00:00 Peilin Ye peilin.ye@bytedance.com 2023-11-14T00:42:16+00:00 6f2684bf2b4460c84d0d34612a939f78b96b03fc Currently veth devices use the lstats per-CPU traffic counters, which only cover TX traffic. veth_get_stats64() actually populates RX stats of a veth device from its peer's TX counters, based on the assumption that a veth device can _only_ receive packets from its peer, which is no longer true: For example, recent CNIs (like Cilium) can use the bpf_redirect_peer() BPF helper to redirect traffic from NIC's tc ingress to veth's tc ingress (in a different netns), skipping veth's peer device. Unfortunately, this kind of traffic isn't currently accounted for in veth's RX stats. In preparation for the fix, use tstats (instead of lstats) to maintain both RX and TX counters for each veth device. We'll use RX counters for bpf_redirect_peer() traffic, and keep using TX counters for the usual "peer-to-peer" traffic. In veth_get_stats64(), calculate RX stats by _adding_ RX count to peer's TX count, in order to cover both kinds of traffic. veth_stats_rx() might need a name change (perhaps to "veth_stats_xdp()") for less confusion, but let's leave it to another patch to keep the fix minimal. Signed-off-by: Peilin Ye <peilin.ye@bytedance.com> Co-developed-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://lore.kernel.org/r/20231114004220.6495-5-daniel@iogearbox.net Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> 
Currently veth devices use the lstats per-CPU traffic counters, which only
cover TX traffic. veth_get_stats64() actually populates RX stats of a veth
device from its peer's TX counters, based on the assumption that a veth
device can _only_ receive packets from its peer, which is no longer true:

For example, recent CNIs (like Cilium) can use the bpf_redirect_peer() BPF
helper to redirect traffic from NIC's tc ingress to veth's tc ingress (in
a different netns), skipping veth's peer device. Unfortunately, this kind
of traffic isn't currently accounted for in veth's RX stats.

In preparation for the fix, use tstats (instead of lstats) to maintain
both RX and TX counters for each veth device. We'll use RX counters for
bpf_redirect_peer() traffic, and keep using TX counters for the usual
"peer-to-peer" traffic. In veth_get_stats64(), calculate RX stats by
_adding_ RX count to peer's TX count, in order to cover both kinds of
traffic.

veth_stats_rx() might need a name change (perhaps to "veth_stats_xdp()")
for less confusion, but let's leave it to another patch to keep the fix
minimal.

Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20231114004220.6495-5-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
net: Move {l,t,d}stats allocation to core and convert veth & vrf 2023-11-20T18:15:16+00:00 Daniel Borkmann daniel@iogearbox.net 2023-11-14T00:42:14+00:00 34d21de99cea9cb17967874313e5b0262527833c Move {l,t,d}stats allocation to the core and let netdevs pick the stats type they need. That way the driver doesn't have to bother with error handling (allocation failure checking, making sure free happens in the right spot, etc) - all happening in the core. Co-developed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Cc: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20231114004220.6495-3-daniel@iogearbox.net Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> 
Move {l,t,d}stats allocation to the core and let netdevs pick the stats
type they need. That way the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc) - all happening in the core.

Co-developed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Cc: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20231114004220.6495-3-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
net: veth: use newly added page pool API for veth with xdp 2023-10-24T02:14:49+00:00 Yunsheng Lin linyunsheng@huawei.com 2023-10-20T09:59:52+00:00 2d0de67da51a90c6acf7bf08d7b0501f45408002 Use page_pool_alloc() API to allocate memory with least memory utilization and performance penalty. Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> CC: Lorenzo Bianconi <lorenzo@kernel.org> CC: Alexander Duyck <alexander.duyck@gmail.com> CC: Liang Chen <liangchen.linux@gmail.com> CC: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20231020095952.11055-6-linyunsheng@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Use page_pool_alloc() API to allocate memory with least
memory utilization and performance penalty.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
CC: Lorenzo Bianconi <lorenzo@kernel.org>
CC: Alexander Duyck <alexander.duyck@gmail.com>
CC: Liang Chen <liangchen.linux@gmail.com>
CC: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20231020095952.11055-6-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
veth: Update XDP feature set when bringing up device 2023-09-12T14:32:56+00:00 Toke Høiland-Jørgensen toke@redhat.com 2023-09-11T13:58:25+00:00 7a6102aa6df0d5d032b4cbc51935d1d4cda17254 There's an early return in veth_set_features() if the device is in a down state, which leads to the XDP feature flags not being updated when enabling GRO while the device is down. Which in turn leads to XDP_REDIRECT not working, because the redirect code now checks the flags. Fix this by updating the feature flags after bringing the device up. Before this patch: NETDEV_XDP_ACT_BASIC: yes NETDEV_XDP_ACT_REDIRECT: yes NETDEV_XDP_ACT_NDO_XMIT: no NETDEV_XDP_ACT_XSK_ZEROCOPY: no NETDEV_XDP_ACT_HW_OFFLOAD: no NETDEV_XDP_ACT_RX_SG: yes NETDEV_XDP_ACT_NDO_XMIT_SG: no After this patch: NETDEV_XDP_ACT_BASIC: yes NETDEV_XDP_ACT_REDIRECT: yes NETDEV_XDP_ACT_NDO_XMIT: yes NETDEV_XDP_ACT_XSK_ZEROCOPY: no NETDEV_XDP_ACT_HW_OFFLOAD: no NETDEV_XDP_ACT_RX_SG: yes NETDEV_XDP_ACT_NDO_XMIT_SG: yes Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag") Fixes: 66c0e13ad236 ("drivers: net: turn on XDP features") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20230911135826.722295-1-toke@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
There's an early return in veth_set_features() if the device is in a down
state, which leads to the XDP feature flags not being updated when enabling
GRO while the device is down. Which in turn leads to XDP_REDIRECT not
working, because the redirect code now checks the flags.

Fix this by updating the feature flags after bringing the device up.

Before this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	no
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	no

After this patch:

NETDEV_XDP_ACT_BASIC:		yes
NETDEV_XDP_ACT_REDIRECT:	yes
NETDEV_XDP_ACT_NDO_XMIT:	yes
NETDEV_XDP_ACT_XSK_ZEROCOPY:	no
NETDEV_XDP_ACT_HW_OFFLOAD:	no
NETDEV_XDP_ACT_RX_SG:		yes
NETDEV_XDP_ACT_NDO_XMIT_SG:	yes

Fixes: fccca038f300 ("veth: take into account device reconfiguration for xdp_features flag")
Fixes: 66c0e13ad236 ("drivers: net: turn on XDP features")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20230911135826.722295-1-toke@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>