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2026-06-17Merge tag 'net-next-7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core & protocols: - Work on removing rtnl_lock protection throughout the stack continues. In this chapter: - don't use rtnl_lock for IPv6 multicast routing configuration - don't take rtnl_lock in ethtool for modern drivers - prepare Qdisc dump callbacks for rtnl_lock removal - Support dumping just ifindex + name of all interfaces, under RCU. It's a common operation for Netlink CLI tools (when translating names to ifindexes) and previously required full rtnl_lock. - Support dumping qdiscs and page pools for a specific netdev. Even tho user space wants a dump of all netdevs, most of the time, the OOO programming model results in repeating the dump for each netdev. Which, in absence of a cache, leads to a O(n^2) behavior. - Flush nexthops once on multi-nexthop removal (e.g. when device goes down), another O(n^2) -> O(n) improvement. - Rehash locally generated traffic to a different nexthop on retransmit timeout. - Honor oif when choosing nexthop for locally generated IPv6 traffic. - Convert TCP Auth Option to crypto library, and drop non-RFC algos. - Increase subflow limits in MPTCP to 64 and endpoint limit to 256. - Support MPTCP signaling of IPv6 address + port (ADD_ADDR). We need to selectively skip reporting of the standard TCP Timestamp option, because they won't fit into the header space together (12 + 30 > 40). - Support using bridge neighbor suppression, Duplicate Address Detection, Gratuitous ARP and unsolicited NA forwarding - in EVPN deployments, e.g. VXLAN fabrics (IPv4 and IPv6). - Improve link state reporting for upper netdevs (e.g. macvlan) over tunnel devices (again, mostly for EVPN deployments). - Support binding GENEVE tunnels to a local address. - Speed up UDP tunnel destruction (remove one synchronize_rcu()). - Support exponential field encoding in multicast (IGMPv3 and MLDv2). - Support attaching PSP crypto offload to containers (veth, netkit). - Add a new IPSec Netlink message XFRM_MSG_MIGRATE_STATE that allows migrating individual IPsec SAs independently of their policies. The existing XFRM_MSG_MIGRATE is tightly coupled to policy+SA migration, lacks SPI for unique SA identification, and cannot express reqid changes or migrate Transport mode selectors. The new interface identifies the SA via SPI and mark, supports reqid changes, address family changes, encap removal, and uses an atomic create+install flow under x->lock to prevent SN/IV reuse during AEAD SA migration. - Implement GRO/GSO support for PPPoE. - Convert sockopt callbacks in a number of protocols to iov_iter. Cross-tree stuff: - Remove support for Crypto TFM cloning (unblocked after the TCP Auth Option rework). This feature regressed performance for all crypto API users, since it changed crypto transformation objects into reference-counted objects. - Add FCrypt-PCBC implementation to rxrpc and remove it from the global crypto API as obsolete and insecure. Wireless: - Major rework of station bandwidth handling, fixing issues with lower capability than AP. - Cleanups for EMLSR spec issues (drafts differed). - More Neighbor Awareness Networking (Wi-Fi Aware) work (multicast, schedule improvements, multi-station etc.) - Some Ultra High Reliability (UHR) / IEEE 802.11bn (D1.4) work (e.g. non-primary channel access, UHR DBE support). - Fine Timing Measurement ranging (i.e. distance measurement) APIs. Netfilter: - Use per-rule hash initval in nf_conncount. This avoids unnecessary lock contention with short keys (e.g. conntrack zones) in different namespaces. - Various safety improvements, both in packet parsing and object lifetimes. Notably add refcounts to conntrack timeout policy. Deletions: - Remove TLS + sockmap integration. TLS wants to pin user pages to avoid a copy, and sockmap wants to write to the input stream. More work on this integration is clearly needed, and we can't find any users (original author admitted that they never deployed it). - Remove support for TLS offload with TCP Offload Engine (the far more common opportunistic offload is retained). The locking looks unfixable (driver sleeps under TCP spin locks) and people from the vendor that added this are AWOL. - Remove more ATM code, trying to leave behind only what PPPoATM needs, AAL5 and br2684 with permanent circuits. - Remove AppleTalk. Let it join hamradio in our out of tree protocol graveyard, I mean, repository. - Disable 32-bit x_tables compatibility (32bit binaries on 64bit kernel) interface in user namespaces. To be deleted completely, soon. - Remove 5/10 MHz support from cfg80211/mac80211. Drivers: - Software: - Support DEVMEM/DMABUF Tx over NETMEM_TX_NO_DMA devices (netkit) - bonding: add knob to strictly follow 802.3ad for link state - New drivers: - Alibaba Elastic Ethernet Adaptor (cloud vNIC). - NXP NETC switch within i.MX94. - DPLL: - Add operational state to pins (implement in zl3073x). - Add generic DPLL type, for daisy-chaining DPLLs (implement in ice). - Ethernet high-speed NICs: - Huawei (hinic3): - enhance tc flow offload support with queue selection, tunnels - nVidia/Mellanox: - avoid over-copying payload to the skb's linear part (up to 60% win for LRO on slow CPUs like ARM64 V2) - expose more per-queue stats over the standard API - support additional, unprivileged PFs in the DPU configuration - support Socket Direct (multi-PF) with switchdev offloads - add a pool / frag allocator for DMA mapped buffers for control objects, save memory on systems with 64kB page size - take advantage of the ability to dynamically change RSS table size, even when table is configured by the user - increase the max RSS table size for even traffic distribution - Ethernet NICs: - Marvell/Aquantia: - AQC113 PTP support - Realtek USB (r8152): - support 10Gbit Link Speeds and Energy-Efficient Ethernet (EEE) - support firmware loaded (for RTL8157/RTL8159) - support for the RTL8159 - Intel (ixgbe): - support Energy-Efficient Ethernet (EEE) on E610 devices - Ethernet switches: - Airoha: - support multiple netdevs on a single GDM block / port - Marvell (mv88e6xxx): - support SERDES of mv88e6321 - Microchip (ksz8/9): - rework the driver callbacks to remove one indirection layer - Motorcomm (yt921x): - support port rate policing - support TBF qdisc offload - support ACL/flower offload - nVidia/Mellanox: - expose per-PG rx_discards - Realtek: - rtl8365mb: bridge offloading and VLAN support - Ethernet PHYs: - Airoha: - support Airoha AN8801R Gigabit PHYs. - Micrel: - implement 3 low-loss cable tunables - Realtek: - support MDI swapping for RTL8226-CG - support MDIO for RTL931x - Qualcomm: - at803x: Rx and Tx clock management for IPQ5018 PHY - Motorcomm: - support YT8522 100M RMII PHY - set drive strength in YT8531s RGMII - TI: - dp83822: add optional external PHY clock - Bluetooth: - hci_sync: add support for HCI_LE_Set_Host_Feature [v2] - SMP: use AES-CMAC library API - Intel: - support Product level reset - support smart trigger dump - Mediatek: - add event filter to filter specific event - Realtek: - fix RTL8761B/BU broken LE extended scan - WiFi: - Broadcom (b43): - new support for a 11n device - MediaTek (mt76): - support mt7927 - mt792x: broken usb transport detection - mt7921: regulatory improvements - Qualcomm (ath9k): - GPIO interface improvements - Qualcomm (ath12k): - WDS support - replace dynamic memory allocation in WMI Rx path - thermal throttling/cooling device support - 6 GHz incumbent interference detection - channel 177 in 5 GHz - Realtek (rt89): - RTL8922AU support - USB 3 mode switch for performance - better monitor radiotap support - RTL8922DE preparations" * tag 'net-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1778 commits) ipv4: fib_rule: Move fib4_rules_exit() to ->exit(). net: serialize netif_running() check in enqueue_to_backlog() net: skmsg: preserve sg.copy across SG transforms appletalk: move the protocol out of tree appletalk: stop storing per-interface state in struct net_device selftests/bpf: test that TLS crypto is rejected on a sockmap socket selftests/bpf: drop the unused kTLS program from test_sockmap selftests/bpf: remove sockmap + ktls tests tls: remove dead sockmap (psock) handling from the SW path tls: reject the combination of TLS and sockmap atm: remove orphaned uAPI for deleted drivers, protocols and SVCs atm: remove unused ATM PHY operations atm: remove the unused pre_send and send_bh device operations atm: remove the unused change_qos device operation atm: remove SVC socket support and the signaling daemon interface atm: remove the local ATM (NSAP) address registry atm: remove dead SONET PHY ioctls atm: remove the unused send_oam / push_oam callbacks atm: remove AAL3/4 transport support net: dsa: sja1105: fix lastused timestamp in flower stats ...
2026-06-16appletalk: move the protocol out of treeJakub Kicinski
AppleTalk has been removed in MacOS X 10.6 (Snow Leopard), in 2009, according to Wikipedia. We recently got a burst of AI generated fixes to this protocol which nobody is reviewing. Let AppleTalk follow AX.25 and hamradio out of the Linux tree. We we will maintain the code at: github.com/linux-netdev/mod-orphan for anyone interested in playing with it. Retain the uAPI for now. No strong reason, simply because I suspect keeping it will be less controversial. Acked-by: Stephen Hemminger <stephen@networkplumber.org> Link: https://patch.msgid.link/20260615222935.947233-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-25docs: sysctl/net: Remove ax25, netrom, rose entriesCosta Shulyupin
These networking subsystems were removed in commit dd8d4bc28ad7 ("net: remove ax25 and amateur radio (hamradio) subsystem"), but the sysctl directory table still listed them. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Costa Shulyupin <costa.shul@redhat.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260515180200.1490926-1-costa.shul@redhat.com>
2026-03-12vsock: add G2H fallback for CIDs not owned by H2G transportAlexander Graf
When no H2G transport is loaded, vsock currently routes all CIDs to the G2H transport (commit 65b422d9b61b ("vsock: forward all packets to the host when no H2G is registered"). Extend that existing behavior: when an H2G transport is loaded but does not claim a given CID, the connection falls back to G2H in the same way. This matters in environments like Nitro Enclaves, where an instance may run nested VMs via vhost-vsock (H2G) while also needing to reach sibling enclaves at higher CIDs through virtio-vsock-pci (G2H). With the old code, any CID > 2 was unconditionally routed to H2G when vhost was loaded, making those enclaves unreachable without setting VMADDR_FLAG_TO_HOST explicitly on every connect. Requiring every application to set VMADDR_FLAG_TO_HOST creates friction: tools like socat, iperf, and others would all need to learn about it. The flag was introduced 6 years ago and I am still not aware of any tool that supports it. Even if there was support, it would be cumbersome to use. The most natural experience is a single CID address space where H2G only wins for CIDs it actually owns, and everything else falls through to G2H, extending the behavior that already exists when H2G is absent. To give user space at least a hint that the kernel applied this logic, automatically set the VMADDR_FLAG_TO_HOST on the remote address so it can determine the path taken via getpeername(). Add a per-network namespace sysctl net.vsock.g2h_fallback (default 1). At 0 it forces strict routing: H2G always wins for CID > VMADDR_CID_HOST, or ENODEV if H2G is not loaded. Signed-off-by: Alexander Graf <graf@amazon.com> Tested-by: syzbot@syzkaller.appspotmail.com Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260304230027.59857-1-graf@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-02-26vsock: document write-once behavior of the child_ns_mode sysctlBobby Eshleman
Update the vsock child_ns_mode documentation to include the new write-once semantics of setting child_ns_mode. The semantics are implemented in a preceding patch in this series. Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260223-vsock-ns-write-once-v3-3-c0cde6959923@meta.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-02-17vsock: document namespace mode sysctlsStefano Garzarella
Add documentation for the vsock per-namespace sysctls (`ns_mode` and `child_ns_mode`) to Documentation/admin-guide/sysctl/net.rst. These sysctls were introduced by commit eafb64f40ca4 ("vsock: add netns to vsock core"). Document the two namespace modes (`global` and `local`), the inheritance behavior of `child_ns_mode`, and the restriction preventing local namespaces from setting `child_ns_mode` to `global`. Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patch.msgid.link/20260216163147.236844-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-25net: expand NETDEV_RSS_KEY_LEN to 256 bytesEric Dumazet
NETDEV_RSS_KEY_LEN has been set to 52 bytes in 2014, until now. Jakub suggested we bump the size to 128 bytes or more. Some drivers (like idpf) were already working around the core limit. Since this change might cause some issues in admin scripts, bump it directly to 256 in one go. tjbp26:~# cat /proc/sys/net/core/netdev_rss_key | wc -c 768 tjbp26:~# ethtool -x eth1 RX flow hash indirection table for eth1 with 32 RX ring(s): ... RSS hash key: fe:16:5b:2f:93:85:c2:c9:c1:ef:bd:60:c6:e0:2b:99:4d:bf:b7:14:c8:1e:8d:cb:31:17:51:da:55:eb:91:d9:9e:f9:89:9b:44:a1:dc:08:72:3a:b3:d6:31:86:9a:fe:02:3a:0d:eb:a1:7c:f5:a3:51:3b:08:56:c9:3f:71:69:01:ba:70:38 RSS hash function: toeplitz: on xor: off crc32: off Suggested-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/netdev/20260122075206.504ec591@kernel.org/ Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260122190349.2771064-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-13net: add net.core.qdisc_max_burstEric Dumazet
In blamed commit, I added a check against the temporary queue built in __dev_xmit_skb(). Idea was to drop packets early, before any spinlock was acquired. if (unlikely(defer_count > READ_ONCE(q->limit))) { kfree_skb_reason(skb, SKB_DROP_REASON_QDISC_DROP); return NET_XMIT_DROP; } It turned out that HTB Qdisc has a zero q->limit. HTB limits packets on a per-class basis. Some of our tests became flaky. Add a new sysctl : net.core.qdisc_max_burst to control how many packets can be stored in the temporary lockless queue. Also add a new QDISC_BURST_DROP drop reason to better diagnose future issues. Thanks Neal ! Fixes: 100dfa74cad9 ("net: dev_queue_xmit() llist adoption") Reported-and-bisected-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20260107104159.3669285-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-11-07net: increase skb_defer_max default to 128Eric Dumazet
skb_defer_max value is very conservative, and can be increased to avoid too many calls to kick_defer_list_purge(). Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Link: https://patch.msgid.link/20251106202935.1776179-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-16net: Introduce net.core.bypass_prot_mem sysctl.Kuniyuki Iwashima
If a socket has sk->sk_bypass_prot_mem flagged, the socket opts out of the global protocol memory accounting. Let's control the flag by a new sysctl knob. The flag is written once during socket(2) and is inherited to child sockets. Tested with a script that creates local socket pairs and send()s a bunch of data without recv()ing. Setup: # mkdir /sys/fs/cgroup/test # echo $$ >> /sys/fs/cgroup/test/cgroup.procs # sysctl -q net.ipv4.tcp_mem="1000 1000 1000" # ulimit -n 524288 Without net.core.bypass_prot_mem, charged to tcp_mem & memcg # python3 pressure.py & # cat /sys/fs/cgroup/test/memory.stat | grep sock sock 22642688 <-------------------------------------- charged to memcg # cat /proc/net/sockstat| grep TCP TCP: inuse 2006 orphan 0 tw 0 alloc 2008 mem 5376 <-- charged to tcp_mem # ss -tn | head -n 5 State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:53188 ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:49972 ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:53868 ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:53554 # nstat | grep Pressure || echo no pressure TcpExtTCPMemoryPressures 1 0.0 With net.core.bypass_prot_mem=1, charged to memcg only: # sysctl -q net.core.bypass_prot_mem=1 # python3 pressure.py & # cat /sys/fs/cgroup/test/memory.stat | grep sock sock 2757468160 <------------------------------------ charged to memcg # cat /proc/net/sockstat | grep TCP TCP: inuse 2006 orphan 0 tw 0 alloc 2008 mem 0 <- NOT charged to tcp_mem # ss -tn | head -n 5 State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB 111000 0 127.0.0.1:36019 127.0.0.1:49026 ESTAB 110000 0 127.0.0.1:36019 127.0.0.1:45630 ESTAB 110000 0 127.0.0.1:36019 127.0.0.1:44870 ESTAB 111000 0 127.0.0.1:36019 127.0.0.1:45274 # nstat | grep Pressure || echo no pressure no pressure Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Link: https://patch.msgid.link/20251014235604.3057003-4-kuniyu@google.com
2025-10-15net: add /proc/sys/net/core/txq_reselection_ms controlEric Dumazet
Add a new sysctl to control how often a queue reselection can happen even if a flow has a persistent queue of skbs in a Qdisc or NIC queue. A value of zero means the feature is disabled. Default is 1000 (1 second). This sysctl is used in the following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20251013152234.842065-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-20net: set net.core.rmem_max and net.core.wmem_max to 4 MBEric Dumazet
SO_RCVBUF and SO_SNDBUF have limited range today, unless distros or system admins change rmem_max and wmem_max. Even iproute2 uses 1 MB SO_RCVBUF which is capped by the kernel. Decouple [rw]mem_max and [rw]mem_default and increase [rw]mem_max to 4 MB. Before: $ sysctl net.core.rmem_default net.core.rmem_max net.core.wmem_default net.core.wmem_max net.core.rmem_default = 212992 net.core.rmem_max = 212992 net.core.wmem_default = 212992 net.core.wmem_max = 212992 After: $ sysctl net.core.rmem_default net.core.rmem_max net.core.wmem_default net.core.wmem_max net.core.rmem_default = 212992 net.core.rmem_max = 4194304 net.core.wmem_default = 212992 net.core.wmem_max = 4194304 Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20250819174030.1986278-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-12ARC: Add eBPF JIT supportShahab Vahedi
This will add eBPF JIT support to the 32-bit ARCv2 processors. The implementation is qualified by running the BPF tests on a Synopsys HSDK board with "ARC HS38 v2.1c at 500 MHz" as the 4-core CPU. The test_bpf.ko reports 2-10 fold improvements in execution time of its tests. For instance: test_bpf: #33 tcpdump port 22 jited:0 704 1766 2104 PASS test_bpf: #33 tcpdump port 22 jited:1 120 224 260 PASS test_bpf: #141 ALU_DIV_X: 4294967295 / 4294967295 = 1 jited:0 238 PASS test_bpf: #141 ALU_DIV_X: 4294967295 / 4294967295 = 1 jited:1 23 PASS test_bpf: #776 JMP32_JGE_K: all ... magnitudes jited:0 2034681 PASS test_bpf: #776 JMP32_JGE_K: all ... magnitudes jited:1 1020022 PASS Deployment and structure ------------------------ The related codes are added to "arch/arc/net": - bpf_jit.h -- The interface that a back-end translator must provide - bpf_jit_core.c -- Knows how to handle the input eBPF byte stream - bpf_jit_arcv2.c -- The back-end code that knows the translation logic The bpf_int_jit_compile() at the end of bpf_jit_core.c is the entrance to the whole process. Normally, the translation is done in one pass, namely the "normal pass". In case some relocations are not known during this pass, some data (arc_jit_data) is allocated for the next pass to come. This possible next (and last) pass is called the "extra pass". 1. Normal pass # The necessary pass 1a. Dry run # Get the whole JIT length, epilogue offset, etc. 1b. Emit phase # Allocate memory and start emitting instructions 2. Extra pass # Only needed if there are relocations to be fixed 2a. Patch relocations Support status -------------- The JIT compiler supports BPF instructions up to "cpu=v4". However, it does not yet provide support for: - Tail calls - Atomic operations - 64-bit division/remainder - BPF_PROBE_MEM* (exception table) The result of "test_bpf" test suite on an HSDK board is: hsdk-lnx# insmod test_bpf.ko test_suite=test_bpf test_bpf: Summary: 863 PASSED, 186 FAILED, [851/851 JIT'ed] All the failing test cases are due to the ones that were not JIT'ed. Categorically, they can be represented as: .-----------.------------.-------------. | test type | opcodes | # of cases | |-----------+------------+-------------| | atomic | 0xC3, 0xDB | 149 | | div64 | 0x37, 0x3F | 22 | | mod64 | 0x97, 0x9F | 15 | `-----------^------------+-------------| | (total) 186 | `-------------' Setup: build config ------------------- The following configs must be set to have a working JIT test: CONFIG_BPF_JIT=y CONFIG_BPF_JIT_ALWAYS_ON=y CONFIG_TEST_BPF=m The following options are not necessary for the tests module, but are good to have: CONFIG_DEBUG_INFO=y # prerequisite for below CONFIG_DEBUG_INFO_BTF=y # so bpftool can generate vmlinux.h CONFIG_FTRACE=y # CONFIG_BPF_SYSCALL=y # all these options lead to CONFIG_KPROBE_EVENTS=y # having CONFIG_BPF_EVENTS=y CONFIG_PERF_EVENTS=y # Some BPF programs provide data through /sys/kernel/debug: CONFIG_DEBUG_FS=y arc# mount -t debugfs debugfs /sys/kernel/debug Setup: elfutils --------------- The libdw.{so,a} library that is used by pahole for processing the final binary must come from elfutils 0.189 or newer. The support for ARCv2 [1] has been added since that version. [1] https://sourceware.org/git/?p=elfutils.git;a=commit;h=de3d46b3e7 Setup: pahole ------------- The line below in linux/scripts/Makefile.btf must be commented out: pahole-flags-$(call test-ge, $(pahole-ver), 121) += --btf_gen_floats Or else, the build will fail: $ make V=1 ... BTF .btf.vmlinux.bin.o pahole -J --btf_gen_floats \ -j --lang_exclude=rust \ --skip_encoding_btf_inconsistent_proto \ --btf_gen_optimized .tmp_vmlinux.btf Complex, interval and imaginary float types are not supported Encountered error while encoding BTF. ... BTFIDS vmlinux ./tools/bpf/resolve_btfids/resolve_btfids vmlinux libbpf: failed to find '.BTF' ELF section in vmlinux FAILED: load BTF from vmlinux: No data available This is due to the fact that the ARC toolchains generate "complex float" DIE entries in libgcc and at the moment, pahole can't handle such entries. Running the tests ----------------- host$ scp /bld/linux/lib/test_bpf.ko arc: arc # sysctl net.core.bpf_jit_enable=1 arc # insmod test_bpf.ko test_suite=test_bpf ... test_bpf: #1048 Staggered jumps: JMP32_JSLE_X jited:1 697811 PASS test_bpf: Summary: 863 PASSED, 186 FAILED, [851/851 JIT'ed] Acknowledgments --------------- - Claudiu Zissulescu for his unwavering support - Yuriy Kolerov for testing and troubleshooting - Vladimir Isaev for the pahole workaround - Sergey Matyukevich for paving the road by adding the interpreter support Signed-off-by: Shahab Vahedi <shahab@synopsys.com> Link: https://lore.kernel.org/r/20240430145604.38592-1-list+bpf@vahedi.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-28net: make SK_MEMORY_PCPU_RESERV tunableAdam Li
This patch adds /proc/sys/net/core/mem_pcpu_rsv sysctl file, to make SK_MEMORY_PCPU_RESERV tunable. Commit 3cd3399dd7a8 ("net: implement per-cpu reserves for memory_allocated") introduced per-cpu forward alloc cache: "Implement a per-cpu cache of +1/-1 MB, to reduce number of changes to sk->sk_prot->memory_allocated, which would otherwise be cause of false sharing." sk_prot->memory_allocated points to global atomic variable: atomic_long_t tcp_memory_allocated ____cacheline_aligned_in_smp; If increasing the per-cpu cache size from 1MB to e.g. 16MB, changes to sk->sk_prot->memory_allocated can be further reduced. Performance may be improved on system with many cores. Signed-off-by: Adam Li <adamli@os.amperecomputing.com> Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-15net: increase optmem_max default valueEric Dumazet
For many years, /proc/sys/net/core/optmem_max default value on a 64bit kernel has been 20 KB. Regular usage of TCP tx zerocopy needs a bit more. Google has used 128KB as the default value for 7 years without any problem. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-21bpf, docs: Add loongarch64 as arch supporting BPF JITTiezhu Yang
As BPF JIT support for loongarch64 was added about one year ago with commit 5dc615520c4d ("LoongArch: Add BPF JIT support"), it is appropriate to add loongarch64 as arch supporting BPF JIT in bpf and sysctl docs as well. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Link: https://lore.kernel.org/r/1695111937-19697-1-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-05-25Documentation: net: net.core.txrehash is not specific to listening socketsAntoine Tenart
The net.core.txrehash documentation mentions this knob is for listening sockets only, while sk_rethink_txhash can be called on SYN and RTO retransmits on all TCP sockets. Remove the listening socket part. Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-02-09net: introduce default_rps_mask netns attributePaolo Abeni
If RPS is enabled, this allows configuring a default rps mask, which is effective since receive queue creation time. A default RPS mask allows the system admin to ensure proper isolation, avoiding races at network namespace or device creation time. The default RPS mask is initially empty, and can be modified via a newly added sysctl entry. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-16bpf: Use bpf_capable() instead of CAP_SYS_ADMIN for blinding decisionYauheni Kaliuta
The full CAP_SYS_ADMIN requirement for blinding looks too strict nowadays. These days given unprivileged BPF is disabled by default, the main users for constant blinding coming from unprivileged in particular via cBPF -> eBPF migration (e.g. old-style socket filters). Signed-off-by: Yauheni Kaliuta <ykaliuta@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220831090655.156434-1-ykaliuta@redhat.com Link: https://lore.kernel.org/bpf/20220905090149.61221-1-ykaliuta@redhat.com
2022-08-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
drivers/net/ethernet/mellanox/mlx5/core/en_fs.c 21234e3a84c7 ("net/mlx5e: Fix use after free in mlx5e_fs_init()") c7eafc5ed068 ("net/mlx5e: Convert ethtool_steering member of flow_steering struct to pointer") https://lore.kernel.org/all/20220825104410.67d4709c@canb.auug.org.au/ https://lore.kernel.org/all/20220823055533.334471-1-saeed@kernel.org/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-24Documentation: sysctl: align cells in second content columnBagas Sanjaya
Stephen Rothwell reported htmldocs warning when merging net-next tree: Documentation/admin-guide/sysctl/net.rst:37: WARNING: Malformed table. Text in column margin in table line 4. ========= =================== = ========== ================== Directory Content Directory Content ========= =================== = ========== ================== 802 E802 protocol mptcp Multipath TCP appletalk Appletalk protocol netfilter Network Filter ax25 AX25 netrom NET/ROM bridge Bridging rose X.25 PLP layer core General parameter tipc TIPC ethernet Ethernet protocol unix Unix domain sockets ipv4 IP version 4 x25 X.25 protocol ipv6 IP version 6 ========= =================== = ========== ================== The warning above is caused by cells in second "Content" column of /proc/sys/net subdirectory table which are in column margin. Align these cells against the column header to fix the warning. Link: https://lore.kernel.org/linux-next/20220823134905.57ed08d5@canb.auug.org.au/ Fixes: 1202cdd665315c ("Remove DECnet support from kernel") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20220824035804.204322-1-bagasdotme@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-24net: Fix data-races around netdev_max_backlog.Kuniyuki Iwashima
While reading netdev_max_backlog, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. While at it, we remove the unnecessary spaces in the doc. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-22Remove DECnet support from kernelStephen Hemminger
DECnet is an obsolete network protocol that receives more attention from kernel janitors than users. It belongs in computer protocol history museum not in Linux kernel. It has been "Orphaned" in kernel since 2010. The iproute2 support for DECnet was dropped in 5.0 release. The documentation link on Sourceforge says it is abandoned there as well. Leave the UAPI alone to keep userspace programs compiling. This means that there is still an empty neighbour table for AF_DECNET. The table of /proc/sys/net entries was updated to match current directories and reformatted to be alphabetical. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Acked-by: David Ahern <dsahern@kernel.org> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-08Documentation: add a description for net.core.high_order_alloc_disableAntoine Tenart
A description is missing for the net.core.high_order_alloc_disable option in admin-guide/sysctl/net.rst ; add it. The above sysctl option was introduced by commit ce27ec60648d ("net: add high_order_alloc_disable sysctl/static key"). Thanks to Eric for running again the benchmark cited in the above commit, showing this knob is now mostly of historical importance. Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20220707080245.180525-1-atenart@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
drivers/net/ethernet/cadence/macb_main.c 5cebb40bc955 ("net: macb: Fix PTP one step sync support") 138badbc21a0 ("net: macb: use NAPI for TX completion path") https://lore.kernel.org/all/20220523111021.31489367@canb.auug.org.au/ net/smc/af_smc.c 75c1edf23b95 ("net/smc: postpone sk_refcnt increment in connect()") 3aba103006bc ("net/smc: align the connect behaviour with TCP") https://lore.kernel.org/all/20220524114408.4bf1af38@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19Documentation: add description for net.core.gro_normal_batchXin Long
Describe it in admin-guide/sysctl/net.rst like other Network core options. Users need to know gro_normal_batch for performance tuning. Fixes: 323ebb61e32b ("net: use listified RX for handling GRO_NORMAL skbs") Reported-by: Prijesh Patel <prpatel@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Edward Cree <ecree.xilinx@gmail.com> Link: https://lore.kernel.org/r/acf8a2c03b91bcde11f67ff89b6050089c0712a3.1652888963.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-16net: add skb_defer_max sysctlEric Dumazet
commit 68822bdf76f1 ("net: generalize skb freeing deferral to per-cpu lists") added another per-cpu cache of skbs. It was expected to be small, and an IPI was forced whenever the list reached 128 skbs. We might need to be able to control more precisely queue capacity and added latency. An IPI is generated whenever queue reaches half capacity. Default value of the new limit is 64. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-31txhash: Add txrehash sysctl descriptionAkhmat Karakotov
Update Documentation/admin-guide/sysctl/net.rst with txrehash usage description. Signed-off-by: Akhmat Karakotov <hmukos@yandex-team.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-30Merge tag 'powerpc-5.13-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Enable KFENCE for 32-bit. - Implement EBPF for 32-bit. - Convert 32-bit to do interrupt entry/exit in C. - Convert 64-bit BookE to do interrupt entry/exit in C. - Changes to our signal handling code to use user_access_begin/end() more extensively. - Add support for time namespaces (CONFIG_TIME_NS) - A series of fixes that allow us to reenable STRICT_KERNEL_RWX. - Other smaller features, fixes & cleanups. Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie, Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin, Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria, Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior, Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar, Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li, Yu Kuai, and Zhang Yunkai. * tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits) powerpc/signal32: Fix erroneous SIGSEGV on RT signal return powerpc: Avoid clang uninitialized warning in __get_user_size_allowed powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n powerpc/kasan: Fix shadow start address with modules powerpc/kernel/iommu: Use largepool as a last resort when !largealloc powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants" powerpc/iommu: Annotate nested lock for lockdep powerpc/iommu: Do not immediately panic when failed IOMMU table allocation powerpc/iommu: Allocate it_map by vmalloc selftests/powerpc: remove unneeded semicolon powerpc/64s: remove unneeded semicolon powerpc/eeh: remove unneeded semicolon powerpc/selftests: Add selftest to test concurrent perf/ptrace events powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR powerpc/selftests/perf-hwbreak: Coalesce event creation code powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR powerpc/configs: Add IBMVNIC to some 64-bit configs selftests/powerpc: Add uaccess flush test ...
2021-04-03powerpc/bpf: Implement extended BPF on PPC32Christophe Leroy
Implement Extended Berkeley Packet Filter on Powerpc 32 Test result with test_bpf module: test_bpf: Summary: 378 PASSED, 0 FAILED, [354/366 JIT'ed] Registers mapping: [BPF_REG_0] = r11-r12 /* function arguments */ [BPF_REG_1] = r3-r4 [BPF_REG_2] = r5-r6 [BPF_REG_3] = r7-r8 [BPF_REG_4] = r9-r10 [BPF_REG_5] = r21-r22 (Args 9 and 10 come in via the stack) /* non volatile registers */ [BPF_REG_6] = r23-r24 [BPF_REG_7] = r25-r26 [BPF_REG_8] = r27-r28 [BPF_REG_9] = r29-r30 /* frame pointer aka BPF_REG_10 */ [BPF_REG_FP] = r17-r18 /* eBPF jit internal registers */ [BPF_REG_AX] = r19-r20 [TMP_REG] = r31 As PPC32 doesn't have a redzone in the stack, a stack frame must always be set in order to host at least the tail count counter. The stack frame remains for tail calls, it is set by the first callee and freed by the last callee. r0 is used as temporary register as much as possible. It is referenced directly in the code in order to avoid misusing it, because some instructions interpret it as value 0 instead of register r0 (ex: addi, addis, stw, lwz, ...) The following operations are not implemented: case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */ case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */ case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */ The following operations are only implemented for power of two constants: case BPF_ALU64 | BPF_MOD | BPF_K: /* dst %= imm */ case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */ Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/61d8b149176ddf99e7d5cef0b6dc1598583ca202.1616430991.git.christophe.leroy@csgroup.eu
2021-03-25net: change netdev_unregister_timeout_secs min value to 1Dmitry Vyukov
netdev_unregister_timeout_secs=0 can lead to printing the "waiting for dev to become free" message every jiffy. This is too frequent and unnecessary. Set the min value to 1 second. Also fix the merge issue introduced by "net: make unregister netdev warning timeout configurable": it changed "refcnt != 1" to "refcnt". Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Suggested-by: Eric Dumazet <edumazet@google.com> Fixes: 5aa3afe107d9 ("net: make unregister netdev warning timeout configurable") Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-23net: make unregister netdev warning timeout configurableDmitry Vyukov
netdev_wait_allrefs() issues a warning if refcount does not drop to 0 after 10 seconds. While 10 second wait generally should not happen under normal workload in normal environment, it seems to fire falsely very often during fuzzing and/or in qemu emulation (~10x slower). At least it's not possible to understand if it's really a false positive or not. Automated testing generally bumps all timeouts to very high values to avoid flake failures. Add net.core.netdev_unregister_timeout_secs sysctl to make the timeout configurable for automated testing systems. Lowering the timeout may also be useful for e.g. manual bisection. The default value matches the current behavior. Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=211877 Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-28docs: admin-guide: net.rst: add a missing blank lineMauro Carvalho Chehab
There's a missing blank line after a literal block, which causes this warning: Documentation/admin-guide/sysctl/net.rst:303: WARNING: Literal block ends without a blank line; unexpected unindent. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/b2545be4a4c71269d10278b5990c3e06c4b65f84.1603791716.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-08-28net: add option to not create fall-back tunnels in root-ns as wellMahesh Bandewar
The sysctl that was added earlier by commit 79134e6ce2c ("net: do not create fallback tunnels for non-default namespaces") to create fall-back only in root-ns. This patch enhances that behavior to provide option not to create fallback tunnels in root-ns as well. Since modules that create fallback tunnels could be built-in and setting the sysctl value after booting is pointless, so added a kernel cmdline options to change this default. The default setting is preseved for backward compatibility. The kernel command line option of fb_tunnels=initns will set the sysctl value to 1 and will create fallback tunnels only in initns while kernel cmdline fb_tunnels=none will set the sysctl value to 2 and fallback tunnels are skipped in every netns. Signed-off-by: Mahesh Bandewar <maheshb@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Maciej Zenczykowski <maze@google.com> Cc: Jian Yang <jianyang@google.com> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-16netns: enable to inherit devconf from current netnsNicolas Dichtel
The goal is to be able to inherit the initial devconf parameters from the current netns, ie the netns where this new netns has been created. This is useful in a containers environment where /proc/sys is read only. For example, if a pod is created with specifics devconf parameters and has the capability to create netns, the user expects to get the same parameters than his 'init_net', which is not the real init_net in this case. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-28docs: networking: convert ipvs-sysctl.txt to ReSTMauro Carvalho Chehab
- add SPDX header; - add a document title; - mark lists as such; - mark code blocks and literals as such; - adjust identation, whitespaces and blank lines; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Acked-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-28docs: networking: convert ip-sysctl.txt to ReSTMauro Carvalho Chehab
- add SPDX header; - adjust titles and chapters, adding proper markups; - mark code blocks and literals as such; - mark lists as such; - mark tables as such; - use footnote markup; - adjust identation, whitespaces and blank lines; - add to networking/index.rst. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-05bpf, doc: Add BPF JIT for RV32G to BPF documentationLuke Nelson
Update filter.txt and admin-guide to mention the BPF JIT for RV32G. Co-developed-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: Luke Nelson <luke.r.nels@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Björn Töpel <bjorn.topel@gmail.com> Acked-by: Björn Töpel <bjorn.topel@gmail.com> Link: https://lore.kernel.org/bpf/20200305050207.4159-4-luke.r.nels@gmail.com
2019-08-08docs: admin-guide: remove references to IPX and token-ringStephen Hemminger
Both IPX and TR have not been supported for a while now. Remove them from the /proc/sys/net documentation. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-15docs: admin-guide: move sysctl directory to itMauro Carvalho Chehab
The stuff under sysctl describes /sys interface from userspace point of view. So, add it to the admin-guide and remove the :orphan: from its index file. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
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