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2021-11-10net: fix premature exit from NAPI state polling in napi_disable()Alexander Lobakin1-2/+5
Commit 719c57197010 ("net: make napi_disable() symmetric with enable") accidentally introduced a bug sometimes leading to a kernel BUG when bringing an iface up/down under heavy traffic load. Prior to this commit, napi_disable() was polling n->state until none of (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC) is set and then always flip them. Now there's a possibility to get away with the NAPIF_STATE_SCHE unset as 'continue' drops us to the cmpxchg() call with an uninitialized variable, rather than straight to another round of the state check. Error path looks like: napi_disable(): unsigned long val, new; /* new is uninitialized */ do { val = READ_ONCE(n->state); /* NAPIF_STATE_NPSVC and/or NAPIF_STATE_SCHED is set */ if (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { /* true */ usleep_range(20, 200); continue; /* go straight to the condition check */ } new = val | <...> } while (cmpxchg(&n->state, val, new) != val); /* state == val, cmpxchg() writes garbage */ napi_enable(): do { val = READ_ONCE(n->state); BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); /* 50/50 boom */ <...> while the typical BUG splat is like: [ 172.652461] ------------[ cut here ]------------ [ 172.652462] kernel BUG at net/core/dev.c:6937! [ 172.656914] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 172.661966] CPU: 36 PID: 2829 Comm: xdp_redirect_cp Tainted: G I 5.15.0 #42 [ 172.670222] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0014.082620210524 08/26/2021 [ 172.680646] RIP: 0010:napi_enable+0x5a/0xd0 [ 172.684832] Code: 07 49 81 cc 00 01 00 00 4c 89 e2 48 89 d8 80 e6 fb f0 48 0f b1 55 10 48 39 c3 74 10 48 8b 5d 10 f6 c7 04 75 3d f6 c3 01 75 b4 <0f> 0b 5b 5d 41 5c c3 65 ff 05 b8 e5 61 53 48 c7 c6 c0 f3 34 ad 48 [ 172.703578] RSP: 0018:ffffa3c9497477a8 EFLAGS: 00010246 [ 172.708803] RAX: ffffa3c96615a014 RBX: 0000000000000000 RCX: ffff8a4b575301a0 < snip > [ 172.782403] Call Trace: [ 172.784857] <TASK> [ 172.786963] ice_up_complete+0x6f/0x210 [ice] [ 172.791349] ice_xdp+0x136/0x320 [ice] [ 172.795108] ? ice_change_mtu+0x180/0x180 [ice] [ 172.799648] dev_xdp_install+0x61/0xe0 [ 172.803401] dev_xdp_attach+0x1e0/0x550 [ 172.807240] dev_change_xdp_fd+0x1e6/0x220 [ 172.811338] do_setlink+0xee8/0x1010 [ 172.814917] rtnl_setlink+0xe5/0x170 [ 172.818499] ? bpf_lsm_binder_set_context_mgr+0x10/0x10 [ 172.823732] ? security_capable+0x36/0x50 < snip > Fix this by replacing 'do { } while (cmpxchg())' with an "infinite" for-loop with an explicit break. From v1 [0]: - just use a for-loop to simplify both the fix and the existing code (Eric). [0] https://lore.kernel.org/netdev/20211110191126.1214-1-alexandr.lobakin@intel.com Fixes: 719c57197010 ("net: make napi_disable() symmetric with enable") Suggested-by: Eric Dumazet <edumazet@google.com> # for-loop Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com> Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20211110195605.1304-1-alexandr.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-09bpf, sockmap: sk_skb data_end access incorrect when src_reg = dst_regJussi Maki1-6/+30
The current conversion of skb->data_end reads like this: ; data_end = (void*)(long)skb->data_end; 559: (79) r1 = *(u64 *)(r2 +200) ; r1 = skb->data 560: (61) r11 = *(u32 *)(r2 +112) ; r11 = skb->len 561: (0f) r1 += r11 562: (61) r11 = *(u32 *)(r2 +116) 563: (1f) r1 -= r11 But similar to the case in 84f44df664e9 ("bpf: sock_ops sk access may stomp registers when dst_reg = src_reg"), the code will read an incorrect skb->len when src == dst. In this case we end up generating this xlated code: ; data_end = (void*)(long)skb->data_end; 559: (79) r1 = *(u64 *)(r1 +200) ; r1 = skb->data 560: (61) r11 = *(u32 *)(r1 +112) ; r11 = (skb->data)->len 561: (0f) r1 += r11 562: (61) r11 = *(u32 *)(r1 +116) 563: (1f) r1 -= r11 ... where line 560 is the reading 4B of (skb->data + 112) instead of the intended skb->len Here the skb pointer in r1 gets set to skb->data and the later deref for skb->len ends up following skb->data instead of skb. This fixes the issue similarly to the patch mentioned above by creating an additional temporary variable and using to store the register when dst_reg = src_reg. We name the variable bpf_temp_reg and place it in the cb context for sk_skb. Then we restore from the temp to ensure nothing is lost. Fixes: 16137b09a66f2 ("bpf: Compute data_end dynamically with JIT code") Signed-off-by: Jussi Maki <joamaki@gmail.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20211103204736.248403-6-john.fastabend@gmail.com
2021-11-09bpf: sockmap, strparser, and tls are reusing qdisc_skb_cb and collidingJohn Fastabend1-0/+22
Strparser is reusing the qdisc_skb_cb struct to stash the skb message handling progress, e.g. offset and length of the skb. First this is poorly named and inherits a struct from qdisc that doesn't reflect the actual usage of cb[] at this layer. But, more importantly strparser is using the following to access its metadata. (struct _strp_msg *)((void *)skb->cb + offsetof(struct qdisc_skb_cb, data)) Where _strp_msg is defined as: struct _strp_msg { struct strp_msg strp; /* 0 8 */ int accum_len; /* 8 4 */ /* size: 12, cachelines: 1, members: 2 */ /* last cacheline: 12 bytes */ }; So we use 12 bytes of ->data[] in struct. However in BPF code running parser and verdict the user has read capabilities into the data[] array as well. Its not too problematic, but we should not be exposing internal state to BPF program. If its really needed then we can use the probe_read() APIs which allow reading kernel memory. And I don't believe cb[] layer poses any API breakage by moving this around because programs can't depend on cb[] across layers. In order to fix another issue with a ctx rewrite we need to stash a temp variable somewhere. To make this work cleanly this patch builds a cb struct for sk_skb types called sk_skb_cb struct. Then we can use this consistently in the strparser, sockmap space. Additionally we can start allowing ->cb[] write access after this. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Jussi Maki <joamaki@gmail.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20211103204736.248403-5-john.fastabend@gmail.com
2021-11-09bpf, sockmap: Use stricter sk state checks in sk_lookup_assignJohn Fastabend2-8/+4
In order to fix an issue with sockets in TCP sockmap redirect cases we plan to allow CLOSE state sockets to exist in the sockmap. However, the check in bpf_sk_lookup_assign() currently only invalidates sockets in the TCP_ESTABLISHED case relying on the checks on sockmap insert to ensure we never SOCK_CLOSE state sockets in the map. To prepare for this change we flip the logic in bpf_sk_lookup_assign() to explicitly test for the accepted cases. Namely, a tcp socket in TCP_LISTEN or a udp socket in TCP_CLOSE state. This also makes the code more resilent to future changes. Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20211103204736.248403-2-john.fastabend@gmail.com
2021-11-04devlink: fix flexible_array.cocci warningGuo Zhengkui1-1/+1
Fix following coccicheck warning: ./net/core/devlink.c:69:6-10: WARNING use flexible-array member instead Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com> Link: https://lore.kernel.org/r/20211103121607.27490-1-guozhengkui@vivo.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-04net: fix possible NULL deref in sock_reserve_memoryEric Dumazet1-1/+1
Sanity check in sock_reserve_memory() was not enough to prevent malicious user to trigger a NULL deref. In this case, the isse is that sk_prot->memory_allocated is NULL. Use standard sk_has_account() helper to deal with this. BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: null-ptr-deref in atomic_long_add_return include/linux/atomic/atomic-instrumented.h:1218 [inline] BUG: KASAN: null-ptr-deref in sk_memory_allocated_add include/net/sock.h:1371 [inline] BUG: KASAN: null-ptr-deref in sock_reserve_memory net/core/sock.c:994 [inline] BUG: KASAN: null-ptr-deref in sock_setsockopt+0x22ab/0x2b30 net/core/sock.c:1443 Write of size 8 at addr 0000000000000000 by task syz-executor.0/11270 CPU: 1 PID: 11270 Comm: syz-executor.0 Not tainted 5.15.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 __kasan_report mm/kasan/report.c:446 [inline] kasan_report.cold+0x66/0xdf mm/kasan/report.c:459 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_long_add_return include/linux/atomic/atomic-instrumented.h:1218 [inline] sk_memory_allocated_add include/net/sock.h:1371 [inline] sock_reserve_memory net/core/sock.c:994 [inline] sock_setsockopt+0x22ab/0x2b30 net/core/sock.c:1443 __sys_setsockopt+0x4f8/0x610 net/socket.c:2172 __do_sys_setsockopt net/socket.c:2187 [inline] __se_sys_setsockopt net/socket.c:2184 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2184 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f56076d5ae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5604c4b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f56077e8f60 RCX: 00007f56076d5ae9 RDX: 0000000000000049 RSI: 0000000000000001 RDI: 0000000000000003 RBP: 00007f560772ff25 R08: 000000000000fec7 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffb61a100f R14: 00007f5604c4b300 R15: 0000000000022000 </TASK> Fixes: 2bb2f5fb21b0 ("net: add new socket option SO_RESERVE_MEM") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-03net: avoid double accounting for pure zerocopy skbsTalal Ahmad2-2/+4
Track skbs containing only zerocopy data and avoid charging them to kernel memory to correctly account the memory utilization for msg_zerocopy. All of the data in such skbs is held in user pages which are already accounted to user. Before this change, they are charged again in kernel in __zerocopy_sg_from_iter. The charging in kernel is excessive because data is not being copied into skb frags. This excessive charging can lead to kernel going into memory pressure state which impacts all sockets in the system adversely. Mark pure zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove charge/uncharge for data in such skbs. Initially, an skb is marked pure zerocopy when it is empty and in zerocopy path. skb can then change from a pure zerocopy skb to mixed data skb (zerocopy and copy data) if it is at tail of write queue and there is room available in it and non-zerocopy data is being sent in the next sendmsg call. At this time sk_mem_charge is done for the pure zerocopied data and the pure zerocopy flag is unmarked. We found that this happens very rarely on workloads that pass MSG_ZEROCOPY. A pure zerocopy skb can later be coalesced into normal skb if they are next to each other in queue but this patch prevents coalescing from happening. This avoids complexity of charging when skb downgrades from pure zerocopy to mixed. This is also rare. In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge for SKB_TRUESIZE(skb_end_offset(skb)) is done for sk_mem_charge in tcp_skb_entail for an skb without data. Testing with the msg_zerocopy.c benchmark between two hosts(100G nics) with zerocopy showed that before this patch the 'sock' variable in memory.stat for cgroup2 that tracks sum of sk_forward_alloc, sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this change it is 0. This is due to no charge to sk_forward_alloc for zerocopy data and shows memory utilization for kernel is lowered. With this commit we don't see the warning we saw in previous commit which resulted in commit 84882cf72cd774cf16fd338bdbf00f69ac9f9194. Signed-off-by: Talal Ahmad <talalahmad@google.com> Acked-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-02net: add and use skb_unclone_keeptruesize() helperEric Dumazet1-13/+1
While commit 097b9146c0e2 ("net: fix up truesize of cloned skb in skb_prepare_for_shift()") fixed immediate issues found when KFENCE was enabled/tested, there are still similar issues, when tcp_trim_head() hits KFENCE while the master skb is cloned. This happens under heavy networking TX workloads, when the TX completion might be delayed after incoming ACK. This patch fixes the WARNING in sk_stream_kill_queues when sk->sk_mem_queued/sk->sk_forward_alloc are not zero. Fixes: d3fb45f370d9 ("mm, kfence: insert KFENCE hooks for SLAB") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Marco Elver <elver@google.com> Link: https://lore.kernel.org/r/20211102004555.1359210-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01Revert "net: avoid double accounting for pure zerocopy skbs"Jakub Kicinski2-4/+2
This reverts commit f1a456f8f3fc5828d8abcad941860380ae147b1d. WARNING: CPU: 1 PID: 6819 at net/core/skbuff.c:5429 skb_try_coalesce+0x78b/0x7e0 CPU: 1 PID: 6819 Comm: xxxxxxx Kdump: loaded Tainted: G S 5.15.0-04194-gd852503f7711 #16 RIP: 0010:skb_try_coalesce+0x78b/0x7e0 Code: e8 2a bf 41 ff 44 8b b3 bc 00 00 00 48 8b 7c 24 30 e8 19 c0 41 ff 44 89 f0 48 03 83 c0 00 00 00 48 89 44 24 40 e9 47 fb ff ff <0f> 0b e9 ca fc ff ff 4c 8d 70 ff 48 83 c0 07 48 89 44 24 38 e9 61 RSP: 0018:ffff88881f449688 EFLAGS: 00010282 RAX: 00000000fffffe96 RBX: ffff8881566e4460 RCX: ffffffff82079f7e RDX: 0000000000000003 RSI: dffffc0000000000 RDI: ffff8881566e47b0 RBP: ffff8881566e46e0 R08: ffffed102619235d R09: ffffed102619235d R10: ffff888130c91ae3 R11: ffffed102619235c R12: ffff88881f4498a0 R13: 0000000000000056 R14: 0000000000000009 R15: ffff888130c91ac0 FS: 00007fec2cbb9700(0000) GS:ffff88881f440000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fec1b060d80 CR3: 00000003acf94005 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> tcp_try_coalesce+0xeb/0x290 ? tcp_parse_options+0x610/0x610 ? mark_held_locks+0x79/0xa0 tcp_queue_rcv+0x69/0x2f0 tcp_rcv_established+0xa49/0xd40 ? tcp_data_queue+0x18a0/0x18a0 tcp_v6_do_rcv+0x1c9/0x880 ? rt6_mtu_change_route+0x100/0x100 tcp_v6_rcv+0x1624/0x1830 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+15
Merge in the fixes we had queued in case there was another -rc. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski2-10/+56
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-11-01 We've added 181 non-merge commits during the last 28 day(s) which contain a total of 280 files changed, 11791 insertions(+), 5879 deletions(-). The main changes are: 1) Fix bpf verifier propagation of 64-bit bounds, from Alexei. 2) Parallelize bpf test_progs, from Yucong and Andrii. 3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus. 4) Improve bpf selftests on s390, from Ilya. 5) bloomfilter bpf map type, from Joanne. 6) Big improvements to JIT tests especially on Mips, from Johan. 7) Support kernel module function calls from bpf, from Kumar. 8) Support typeless and weak ksym in light skeleton, from Kumar. 9) Disallow unprivileged bpf by default, from Pawan. 10) BTF_KIND_DECL_TAG support, from Yonghong. 11) Various bpftool cleanups, from Quentin. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits) libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose bpf: Factor out helpers for ctx access checking bpf: Factor out a helper to prepare trampoline for struct_ops prog selftests, bpf: Fix broken riscv build riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h tools, build: Add RISC-V to HOSTARCH parsing riscv, bpf: Increase the maximum number of iterations selftests, bpf: Add one test for sockmap with strparser selftests, bpf: Fix test_txmsg_ingress_parser error ... ==================== Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01net: avoid double accounting for pure zerocopy skbsTalal Ahmad2-2/+4
Track skbs with only zerocopy data and avoid charging them to kernel memory to correctly account the memory utilization for msg_zerocopy. All of the data in such skbs is held in user pages which are already accounted to user. Before this change, they are charged again in kernel in __zerocopy_sg_from_iter. The charging in kernel is excessive because data is not being copied into skb frags. This excessive charging can lead to kernel going into memory pressure state which impacts all sockets in the system adversely. Mark pure zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove charge/uncharge for data in such skbs. Initially, an skb is marked pure zerocopy when it is empty and in zerocopy path. skb can then change from a pure zerocopy skb to mixed data skb (zerocopy and copy data) if it is at tail of write queue and there is room available in it and non-zerocopy data is being sent in the next sendmsg call. At this time sk_mem_charge is done for the pure zerocopied data and the pure zerocopy flag is unmarked. We found that this happens very rarely on workloads that pass MSG_ZEROCOPY. A pure zerocopy skb can later be coalesced into normal skb if they are next to each other in queue but this patch prevents coalescing from happening. This avoids complexity of charging when skb downgrades from pure zerocopy to mixed. This is also rare. In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge for SKB_TRUESIZE(MAX_TCP_HEADER) is done for sk_mem_charge in tcp_skb_entail for an skb without data. Testing with the msg_zerocopy.c benchmark between two hosts(100G nics) with zerocopy showed that before this patch the 'sock' variable in memory.stat for cgroup2 that tracks sum of sk_forward_alloc, sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this change it is 0. This is due to no charge to sk_forward_alloc for zerocopy data and shows memory utilization for kernel is lowered. Signed-off-by: Talal Ahmad <talalahmad@google.com> Acked-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01skmsg: Lose offset info in sk_psock_skb_ingressLiu Jian1-10/+33
If sockmap enable strparser, there are lose offset info in sk_psock_skb_ingress(). If the length determined by parse_msg function is not skb->len, the skb will be converted to sk_msg multiple times, and userspace app will get the data multiple times. Fix this by get the offset and length from strp_msg. And as Cong suggested, add one bit in skb->_sk_redir to distinguish enable or disable strparser. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Cong Wang <cong.wang@bytedance.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20211029141216.211899-1-liujian56@huawei.com
2021-11-01ethtool: don't drop the rtnl_lock half way thru the ioctlJakub Kicinski1-38/+7
devlink compat code needs to drop rtnl_lock to take devlink->lock to ensure correct lock ordering. This is problematic because we're not strictly guaranteed that the netdev will not disappear after we re-lock. It may open a possibility of nested ->begin / ->complete calls. Instead of calling into devlink under rtnl_lock take a ref on the devlink instance and make the call after we've dropped rtnl_lock. We (continue to) assume that netdevs have an implicit reference on the devlink returned from ndo_get_devlink_port Note that ndo_get_devlink_port will now get called under rtnl_lock. That should be fine since none of the drivers seem to be taking serious locks inside ndo_get_devlink_port. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-01devlink: expose get/put functionsJakub Kicinski1-3/+5
Allow those who hold implicit reference on a devlink instance to try to take a full ref on it. This will be used from netdev code which has an implicit ref because of driver call ordering. Note that after recent changes devlink_unregister() may happen before netdev unregister, but devlink_free() should still happen after, so we are safe to try, but we can't just refcount_inc() and assume it's not zero. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-01ethtool: push the rtnl_lock into dev_ethtool()Jakub Kicinski1-2/+0
Don't take the lock in net/core/dev_ioctl.c, we'll have things to do outside rtnl_lock soon. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-29cls_flower: Fix inability to match GRE/IPIP packetsYoshiki Komachi1-0/+15
When a packet of a new flow arrives in openvswitch kernel module, it dissects the packet and passes the extracted flow key to ovs-vswtichd daemon. If hw- offload configuration is enabled, the daemon creates a new TC flower entry to bypass openvswitch kernel module for the flow (TC flower can also offload flows to NICs but this time that does not matter). In this processing flow, I found the following issue in cases of GRE/IPIP packets. When ovs_flow_key_extract() in openvswitch module parses a packet of a new GRE (or IPIP) flow received on non-tunneling vports, it extracts information of the outer IP header for ip_proto/src_ip/dst_ip match keys. This means ovs-vswitchd creates a TC flower entry with IP protocol/addresses match keys whose values are those of the outer IP header. OTOH, TC flower, which uses flow_dissector (different parser from openvswitch module), extracts information of the inner IP header. The following flow is an example to describe the issue in more detail. <----------- Outer IP -----------------> <---------- Inner IP ----------> +----------+--------------+--------------+----------+----------+----------+ | ip_proto | src_ip | dst_ip | ip_proto | src_ip | dst_ip | | 47 (GRE) | 192.168.10.1 | 192.168.10.2 | 6 (TCP) | 10.0.0.1 | 10.0.0.2 | +----------+--------------+--------------+----------+----------+----------+ In this case, TC flower entry and extracted information are shown as below: - ovs-vswitchd creates TC flower entry with: - ip_proto: 47 - src_ip: 192.168.10.1 - dst_ip: 192.168.10.2 - TC flower extracts below for IP header matches: - ip_proto: 6 - src_ip: 10.0.0.1 - dst_ip: 10.0.0.2 Thus, GRE or IPIP packets never match the TC flower entry, as each dissector behaves differently. IMHO, the behavior of TC flower (flow dissector) does not look correct, as ip_proto/src_ip/dst_ip in TC flower match means the outermost IP header information except for GRE/IPIP cases. This patch adds a new flow_dissector flag FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP which skips dissection of the encapsulated inner GRE/IPIP header in TC flower classifier. Signed-off-by: Yoshiki Komachi <komachi.yoshiki@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-29devlink: make all symbols GPL-onlyJakub Kicinski1-4/+4
devlink_alloc() and devlink_register() are both GPL. A non-GPL module won't get far, so for consistency we can make all symbols GPL without risking any real life breakage. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-29mctp: Add flow extension to skbJeremy Kerr1-0/+19
This change adds a new skb extension for MCTP, to represent a request/response flow. The intention is to use this in a later change to allow i2c controllers to correctly configure a multiplexer over a flow. Since we have a cleanup function in the core path (if an extension is present), we'll need to make CONFIG_MCTP a bool, rather than a tristate. Includes a fix for a build warning with clang: Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski6-17/+60
include/net/sock.h 7b50ecfcc6cd ("net: Rename ->stream_memory_read to ->sock_is_readable") 4c1e34c0dbff ("vsock: Enable y2038 safe timeval for timeout") drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c 0daa55d033b0 ("octeontx2-af: cn10k: debugfs for dumping LMTST map table") e77bcdd1f639 ("octeontx2-af: Display all enabled PF VF rsrc_alloc entries.") Adjacent code addition in both cases, keep both. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-28devlink: Simplify internal devlink params implementationLeon Romanovsky1-123/+46
Reduce extra indirection from devlink_params_*() API. Such change makes it clear that we can drop devlink->lock from these flows, because everything is executed when the devlink is not registered yet. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-27xdp: Remove redundant warningYajun Deng1-2/+0
There is a warning in xdp_rxq_info_unreg_mem_model() when reg_state isn't equal to REG_STATE_REGISTERED, so the warning in xdp_rxq_info_unreg() is redundant. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Link: https://lore.kernel.org/r/20211027013856.1866-1-yajun.deng@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27Revert "devlink: Remove not-executed trap policer notifications"Leon Romanovsky1-5/+7
This reverts commit 22849b5ea5952d853547cc5e0651f34a246b2a4f as it revealed that mlxsw and netdevsim (copy/paste from mlxsw) reregisters devlink objects during another devlink user triggered command. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27Revert "devlink: Remove not-executed trap group notifications"Leon Romanovsky1-5/+7
This reverts commit 8bbeed4858239ac956a78e5cbaf778bd6f3baef8 as it revealed that mlxsw and netdevsim (copy/paste from mlxsw) reregisters devlink objects during another devlink user triggered command. Fixes: 22849b5ea595 ("devlink: Remove not-executed trap policer notifications") Reported-by: syzbot+93d5accfaefceedf43c1@syzkaller.appspotmail.com Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-26net: Prevent HW-GRO and LRO features operate togetherBen Ben-ishay1-0/+5
LRO and HW-GRO are mutually exclusive, this commit adds this restriction in netdev_fix_feature. HW-GRO is preferred, that means in case both HW-GRO and LRO features are requested, LRO is cleared. Signed-off-by: Ben Ben-ishay <benishay@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
2021-10-26Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfJakub Kicinski2-1/+15
Daniel Borkmann says: ==================== pull-request: bpf 2021-10-26 We've added 12 non-merge commits during the last 7 day(s) which contain a total of 23 files changed, 118 insertions(+), 98 deletions(-). The main changes are: 1) Fix potential race window in BPF tail call compatibility check, from Toke Høiland-Jørgensen. 2) Fix memory leak in cgroup fs due to missing cgroup_bpf_offline(), from Quanyang Wang. 3) Fix file descriptor reference counting in generic_map_update_batch(), from Xu Kuohai. 4) Fix bpf_jit_limit knob to the max supported limit by the arch's JIT, from Lorenz Bauer. 5) Fix BPF sockmap ->poll callbacks for UDP and AF_UNIX sockets, from Cong Wang and Yucong Sun. 6) Fix BPF sockmap concurrency issue in TCP on non-blocking sendmsg calls, from Liu Jian. 7) Fix build failure of INODE_STORAGE and TASK_STORAGE maps on !CONFIG_NET, from Tejun Heo. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Fix potential race in tail call compatibility check bpf: Move BPF_MAP_TYPE for INODE_STORAGE and TASK_STORAGE outside of CONFIG_NET selftests/bpf: Use recv_timeout() instead of retries net: Implement ->sock_is_readable() for UDP and AF_UNIX skmsg: Extract and reuse sk_msg_is_readable() net: Rename ->stream_memory_read to ->sock_is_readable tcp_bpf: Fix one concurrency problem in the tcp_bpf_send_verdict function cgroup: Fix memory leak caused by missing cgroup_bpf_offline bpf: Fix error usage of map_fd and fdget() in generic_map_update_batch() bpf: Prevent increasing bpf_jit_limit above max bpf: Define bpf_jit_alloc_exec_limit for arm64 JIT bpf: Define bpf_jit_alloc_exec_limit for riscv JIT ==================== Link: https://lore.kernel.org/r/20211026201920.11296-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-26skmsg: Extract and reuse sk_msg_is_readable()Cong Wang1-0/+14
tcp_bpf_sock_is_readable() is pretty much generic, we can extract it and reuse it for non-TCP sockets. Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211008203306.37525-3-xiyou.wangcong@gmail.com
2021-10-26net: multicast: calculate csum of looped-back and forwarded packetsCyril Strejc1-1/+2
During a testing of an user-space application which transmits UDP multicast datagrams and utilizes multicast routing to send the UDP datagrams out of defined network interfaces, I've found a multicast router does not fill-in UDP checksum into locally produced, looped-back and forwarded UDP datagrams, if an original output NIC the datagrams are sent to has UDP TX checksum offload enabled. The datagrams are sent malformed out of the NIC the datagrams have been forwarded to. It is because: 1. If TX checksum offload is enabled on the output NIC, UDP checksum is not calculated by kernel and is not filled into skb data. 2. dev_loopback_xmit(), which is called solely by ip_mc_finish_output(), sets skb->ip_summed = CHECKSUM_UNNECESSARY unconditionally. 3. Since 35fc92a9 ("[NET]: Allow forwarding of ip_summed except CHECKSUM_COMPLETE"), the ip_summed value is preserved during forwarding. 4. If ip_summed != CHECKSUM_PARTIAL, checksum is not calculated during a packet egress. The minimum fix in dev_loopback_xmit(): 1. Preserves skb->ip_summed CHECKSUM_PARTIAL. This is the case when the original output NIC has TX checksum offload enabled. The effects are: a) If the forwarding destination interface supports TX checksum offloading, the NIC driver is responsible to fill-in the checksum. b) If the forwarding destination interface does NOT support TX checksum offloading, checksums are filled-in by kernel before skb is submitted to the NIC driver. c) For local delivery, checksum validation is skipped as in the case of CHECKSUM_UNNECESSARY, thanks to skb_csum_unnecessary(). 2. Translates ip_summed CHECKSUM_NONE to CHECKSUM_UNNECESSARY. It means, for CHECKSUM_NONE, the behavior is unmodified and is there to skip a looped-back packet local delivery checksum validation. Signed-off-by: Cyril Strejc <cyril.strejc@skoda.cz> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-25net-sysfs: initialize uid and gid before calling net_ns_get_ownershipXin Long1-2/+2
Currently in net_ns_get_ownership() it may not be able to set uid or gid if make_kuid or make_kgid returns an invalid value, and an uninit-value issue can be triggered by this. This patch is to fix it by initializing the uid and gid before calling net_ns_get_ownership(), as it does in kobject_get_ownership() Fixes: e6dee9f3893c ("net-sysfs: add netdev_change_owner()") Reported-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-25net: Prevent infinite while loop in skb_tx_hash()Michael Chan1-0/+6
Drivers call netdev_set_num_tc() and then netdev_set_tc_queue() to set the queue count and offset for each TC. So the queue count and offset for the TCs may be zero for a short period after dev->num_tc has been set. If a TX packet is being transmitted at this time in the code path netdev_pick_tx() -> skb_tx_hash(), skb_tx_hash() may see nonzero dev->num_tc but zero qcount for the TC. The while loop that keeps looping while hash >= qcount will not end. Fix it by checking the TC's qcount to be nonzero before using it. Fixes: eadec877ce9c ("net: Add support for subordinate traffic classes to netdev_pick_tx") Reviewed-by: Andy Gospodarek <gospo@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-24net: rtnetlink: use __dev_addr_set()Jakub Kicinski1-2/+2
Get it ready for constant netdev->dev_addr. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-24net: core: constify mac addrs in selftestsJakub Kicinski1-4/+4
Get it ready for constant netdev->dev_addr. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-22bpf: Prevent increasing bpf_jit_limit above maxLorenz Bauer1-1/+1
Restrict bpf_jit_limit to the maximum supported by the arch's JIT. Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211014142554.53120-4-lmb@cloudflare.com
2021-10-22devlink: Clean not-executed param notificationsLeon Romanovsky1-4/+11
The parameters are registered before devlink_register() and all the notifications are delayed. This patch removes not-possible parameters notifications along with addition of code annotation logic. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-22devlink: Remove not-executed trap group notificationsLeon Romanovsky1-7/+5
The trap logic is registered before devlink_register() and all the notifications are delayed. This patch removes not-possible trap group notifications along with addition of code annotation logic. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-22devlink: Remove not-executed trap policer notificationsLeon Romanovsky1-7/+5
The trap policer logic is registered before devlink_register() and all the notifications are delayed. This patch removes not-possible notifications along with addition of code annotation logic. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-22devlink: Delete obsolete parameters publish APILeon Romanovsky1-49/+8
The change of devlink_register() to be last devlink command together with delayed notification logic made the publish API to be obsolete. Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-22skb_expand_head() adjust skb->truesize incorrectlyVasily Averin2-13/+35
Christoph Paasch reports [1] about incorrect skb->truesize after skb_expand_head() call in ip6_xmit. This may happen because of two reasons: - skb_set_owner_w() for newly cloned skb is called too early, before pskb_expand_head() where truesize is adjusted for (!skb-sk) case. - pskb_expand_head() does not adjust truesize in (skb->sk) case. In this case sk->sk_wmem_alloc should be adjusted too. [1] https://lkml.org/lkml/2021/8/20/1082 Fixes: f1260ff15a71 ("skbuff: introduce skb_expand_head()") Fixes: 2d85a1b31dde ("ipv6: ip6_finish_output2: set sk into newly allocated nskb") Reported-by: Christoph Paasch <christoph.paasch@gmail.com> Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/644330dd-477e-0462-83bf-9f514c41edd1@virtuozzo.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-21bpf: Add bpf_skc_to_unix_sock() helperHengqi Chen1-0/+23
The helper is used in tracing programs to cast a socket pointer to a unix_sock pointer. The return value could be NULL if the casting is illegal. Suggested-by: Yonghong Song <yhs@fb.com> Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20211021134752.1223426-2-hengqi.chen@gmail.com
2021-10-21net/core: Remove unused assignment operations and variableluo penghao1-2/+1
Although if_info_size is assigned, it has not been used. And the variable should also be deleted. The clang_analyzer complains as follows: net/core/rtnetlink.c:3806: warning: Although the value stored to 'if_info_size' is used in the enclosing expression, the value is never actually read from 'if_info_size'. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: luo penghao <luo.penghao@zte.com.cn> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-21net: stats: Read the statistics in ___gnet_stats_copy_basic() instead of adding.Sebastian Andrzej Siewior1-6/+37
Since the rework, the statistics code always adds up the byte and packet value(s). On 32bit architectures a seqcount_t is used in gnet_stats_basic_sync to ensure that the 64bit values are not modified during the read since two 32bit loads are required. The usage of a seqcount_t requires a lock to ensure that only one writer is active at a time. This lock leads to disabled preemption during the update. The lack of disabling preemption is now creating a warning as reported by Naresh since the query done by gnet_stats_copy_basic() is in preemptible context. For ___gnet_stats_copy_basic() there is no need to disable preemption since the update is performed on stack and can't be modified by another writer. Instead of disabling preemption, to avoid the warning, simply create a read function to just read the values and return as u64. Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Fixes: 67c9e6270f301 ("net: sched: Protect Qdisc::bstats with u64_stats") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-20net-core: use netdev_* calls for kernel messagesJesse Brandeburg1-12/+10
While loading a driver and changing the number of queues, I noticed this message in the kernel log: "[253489.070080] Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!" But I had no idea what interface was being talked about because this message used pr_warn(). After investigating, it appears we can use the netdev_* helpers already defined to create predictably formatted messages, and that already handle <unknown netdev> cases, in more of the messages in dev.c. After this change, this message (and others) will look like this: "[ 170.181093] ice 0000:3b:00.0 ens785f0: Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!" One goal here was not to change the message significantly from the original format so as to not break user's expectations, so I just changed messages that used pr_* and generally started with %s == dev->name. Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-19devlink: Remove extra device_lock assert checksLeon Romanovsky1-2/+0
PCI core code in the pci_call_probe() has a path that doesn't hold device_lock. It happens because the ->probe() is called through the workqueue mechanism. 349 static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, 350 const struct pci_device_id *id) 351 { 352 .... 377 if (cpu < nr_cpu_ids) 378 error = work_on_cpu(cpu, local_pci_probe, &ddi); Luckily enough, the core still ensures that only single flow is executed, so it safe to remove the assert checks that anyway were added for annotations purposes. Fixes: b88f7b1203bf ("devlink: Annotate devlink API calls") Reported-by: Amit Cohen <amcohen@nvidia.com> Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-19net: sched: Allow statistics reads from softirq.Sebastian Andrzej Siewior1-1/+1
Eric reported that the rate estimator reads statics from the softirq which in turn triggers a warning introduced in the statistics rework. The warning is too cautious. The updates happen in the softirq context so reads from softirq are fine since the writes can not be preempted. The updates/writes happen during qdisc_run() which ensures one writer and the softirq context. The remaining bad context for reading statistics remains in hard-IRQ because it may preempt a writer. Fixes: 29cbcd8582837 ("net: sched: Remove Qdisc::running sequence counter") Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller1-4/+15
Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following patchset contains Netfilter/IPVS for net-next: 1) Add new run_estimation toggle to IPVS to stop the estimation_timer logic, from Dust Li. 2) Relax superfluous dynset check on NFT_SET_TIMEOUT. 3) Add egress hook, from Lukas Wunner. 4) Nowadays, almost all hook functions in x_table land just call the hook evaluation loop. Remove remaining hook wrappers from iptables and IPVS. From Florian Westphal. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18net: sched: Remove Qdisc::running sequence counterAhmed S. Darwish2-28/+38
The Qdisc::running sequence counter has two uses: 1. Reliably reading qdisc's tc statistics while the qdisc is running (a seqcount read/retry loop at gnet_stats_add_basic()). 2. As a flag, indicating whether the qdisc in question is running (without any retry loops). For the first usage, the Qdisc::running sequence counter write section, qdisc_run_begin() => qdisc_run_end(), covers a much wider area than what is actually needed: the raw qdisc's bstats update. A u64_stats sync point was thus introduced (in previous commits) inside the bstats structure itself. A local u64_stats write section is then started and stopped for the bstats updates. Use that u64_stats sync point mechanism for the bstats read/retry loop at gnet_stats_add_basic(). For the second qdisc->running usage, a __QDISC_STATE_RUNNING bit flag, accessed with atomic bitops, is sufficient. Using a bit flag instead of a sequence counter at qdisc_run_begin/end() and qdisc_is_running() leads to the SMP barriers implicitly added through raw_read_seqcount() and write_seqcount_begin/end() getting removed. All call sites have been surveyed though, and no required ordering was identified. Now that the qdisc->running sequence counter is no longer used, remove it. Note, using u64_stats implies no sequence counter protection for 64-bit architectures. This can lead to the qdisc tc statistics "packets" vs. "bytes" values getting out of sync on rare occasions. The individual values will still be valid. Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18net: sched: Merge Qdisc::bstats and Qdisc::cpu_bstats data typesAhmed S. Darwish2-45/+53
The only factor differentiating per-CPU bstats data type (struct gnet_stats_basic_cpu) from the packed non-per-CPU one (struct gnet_stats_basic_packed) was a u64_stats sync point inside the former. The two data types are now equivalent: earlier commits added a u64_stats sync point to the latter. Combine both data types into "struct gnet_stats_basic_sync". This eliminates redundancy and simplifies the bstats read/write APIs. Use u64_stats_t for bstats "packets" and "bytes" data types. On 64-bit architectures, u64_stats sync points do not use sequence counter protection. Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18net: sched: Use _bstats_update/set() instead of raw writesAhmed S. Darwish1-4/+5
The Qdisc::running sequence counter, used to protect Qdisc::bstats reads from parallel writes, is in the process of being removed. Qdisc::bstats read/writes will synchronize using an internal u64_stats sync point instead. Modify all bstats writes to use _bstats_update(). This ensures that the internal u64_stats sync point is always acquired and released as appropriate. Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18net: sched: Protect Qdisc::bstats with u64_statsAhmed S. Darwish2-3/+13
The not-per-CPU variant of qdisc tc (traffic control) statistics, Qdisc::gnet_stats_basic_packed bstats, is protected with Qdisc::running sequence counter. This sequence counter is used for reliably protecting bstats reads from parallel writes. Meanwhile, the seqcount's write section covers a much wider area than bstats update: qdisc_run_begin() => qdisc_run_end(). That read/write section asymmetry can lead to needless retries of the read section. To prepare for removing the Qdisc::running sequence counter altogether, introduce a u64_stats sync point inside bstats instead. Modify _bstats_update() to start/end the bstats u64_stats write section. For bisectability, and finer commits granularity, the bstats read section is still protected with a Qdisc::running read/retry loop and qdisc_run_begin/end() still starts/ends that seqcount write section. Once all call sites are modified to use _bstats_update(), the Qdisc::running seqcount will be removed and bstats read/retry loop will be modified to utilize the internal u64_stats sync point. Note, using u64_stats implies no sequence counter protection for 64-bit architectures. This can lead to the statistics "packets" vs. "bytes" values getting out of sync on rare occasions. The individual values will still be valid. [bigeasy: Minor commit message edits, init all gnet_stats_basic_packed.] Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-18gen_stats: Move remaining users to gnet_stats_add_queue().Sebastian Andrzej Siewior1-37/+2
The gnet_stats_queue::qlen member is only used in the SMP-case. qdisc_qstats_qlen_backlog() needs to add qdisc_qlen() to qstats.qlen to have the same value as that provided by qdisc_qlen_sum(). gnet_stats_copy_queue() needs to overwritte the resulting qstats.qlen field whith the caller submitted qlen value. It might be differ from the submitted value. Let both functions use gnet_stats_add_queue() and remove unused __gnet_stats_copy_queue(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-19 14:03:04 +0000