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Commit Graph

2382 Commits

Author SHA1 Message Date
Jakub Kicinski
cb7103298d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.15-rc2).

Conflict:

Documentation/networking/netdevices.rst
net/core/lock_debug.c
  04efcee6ef ("net: hold instance lock during NETDEV_CHANGE")
  03df156dd3 ("xdp: double protect netdev->xdp_flags with netdev->lock")

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-10 16:51:07 -07:00
Jakub Kicinski
4ec9031cbe netdev: add "ops compat locking" helpers
Add helpers to "lock a netdev in a backward-compatible way",
which for ops-locked netdevs will mean take the instance lock.
For drivers which haven't opted into the ops locking we'll take
rtnl_lock.

The scoped foreach is dropping and re-taking the lock for each
device, even if prev and next are both under rtnl_lock.
I hope that's fine since we expect that netdev nl to be mostly
supported by modern drivers, and modern drivers should also
opt into the instance locking.

Note that these helpers are mostly needed for queue related state,
because drivers modify queue config in their ops in a non-atomic
way. Or differently put, queue changes don't have a clear-cut API
like NAPI configuration. Any state that can should just use the
instance lock directly, not the "compat" hacks.

Reviewed-by: Joe Damato <jdamato@fastly.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250408195956.412733-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-09 17:01:51 -07:00
Jakub Kicinski
a82dc19db1 net: avoid potential race between netdev_get_by_index_lock() and netns switch
netdev_get_by_index_lock() performs following steps:

  rcu_lock();
  dev = lookup(netns, ifindex);
  dev_get(dev);
  rcu_unlock();
  [... lock & validate the dev ...]
  return dev

Validation right now only checks if the device is registered but since
the lookup is netns-aware we must also protect against the device
switching netns right after we dropped the RCU lock. Otherwise
the caller in netns1 may get a pointer to a device which has just
switched to netns2.

We can't hold the lock for the entire netns change process (because of
the NETDEV_UNREGISTER notifier), and there's no existing marking to
indicate that the netns is unlisted because of netns move, so add one.

AFAIU none of the existing netdev_get_by_index_lock() callers can
suffer from this problem (NAPI code double checks the netns membership
and other callers are either under rtnl_lock or not ns-sensitive),
so this patch does not have to be treated as a fix.

Reviewed-by: Joe Damato <jdamato@fastly.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250408195956.412733-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-09 17:01:51 -07:00
Eric Dumazet
22d046a778 net: add data-race annotations in softnet_seq_show()
softnet_seq_show() reads several fields that might be updated
concurrently. Add READ_ONCE() and WRITE_ONCE() annotations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250407163602.170356-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-08 12:30:55 -07:00
Eric Dumazet
7b6f0a852d net: rps: annotate data-races around (struct sd_flow_limit)->count
softnet_seq_show() can read fl->count while another cpu
updates this field from skb_flow_limit().

Make this field an 'unsigned int', as its only consumer
only deals with 32 bit.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250407163602.170356-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-08 12:30:55 -07:00
Eric Dumazet
c3025e94da net: rps: change skb_flow_limit() hash function
As explained in commit f3483c8e1d ("net: rfs: hash function change"),
masking low order bits of skb_get_hash(skb) has low entropy.

A NIC with 32 RX queues uses the 5 low order bits of rss key
to select a queue. This means all packets landing to a given
queue share the same 5 low order bits.

Switch to hash_32() to reduce hash collisions.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250407163602.170356-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-08 12:30:55 -07:00
Stanislav Fomichev
04efcee6ef net: hold instance lock during NETDEV_CHANGE
Cosmin reports an issue with ipv6_add_dev being called from
NETDEV_CHANGE notifier:

[ 3455.008776]  ? ipv6_add_dev+0x370/0x620
[ 3455.010097]  ipv6_find_idev+0x96/0xe0
[ 3455.010725]  addrconf_add_dev+0x1e/0xa0
[ 3455.011382]  addrconf_init_auto_addrs+0xb0/0x720
[ 3455.013537]  addrconf_notify+0x35f/0x8d0
[ 3455.014214]  notifier_call_chain+0x38/0xf0
[ 3455.014903]  netdev_state_change+0x65/0x90
[ 3455.015586]  linkwatch_do_dev+0x5a/0x70
[ 3455.016238]  rtnl_getlink+0x241/0x3e0
[ 3455.019046]  rtnetlink_rcv_msg+0x177/0x5e0

Similarly, linkwatch might get to ipv6_add_dev without ops lock:
[ 3456.656261]  ? ipv6_add_dev+0x370/0x620
[ 3456.660039]  ipv6_find_idev+0x96/0xe0
[ 3456.660445]  addrconf_add_dev+0x1e/0xa0
[ 3456.660861]  addrconf_init_auto_addrs+0xb0/0x720
[ 3456.661803]  addrconf_notify+0x35f/0x8d0
[ 3456.662236]  notifier_call_chain+0x38/0xf0
[ 3456.662676]  netdev_state_change+0x65/0x90
[ 3456.663112]  linkwatch_do_dev+0x5a/0x70
[ 3456.663529]  __linkwatch_run_queue+0xeb/0x200
[ 3456.663990]  linkwatch_event+0x21/0x30
[ 3456.664399]  process_one_work+0x211/0x610
[ 3456.664828]  worker_thread+0x1cc/0x380
[ 3456.665691]  kthread+0xf4/0x210

Reclassify NETDEV_CHANGE as a notifier that consistently runs under the
instance lock.

Link: https://lore.kernel.org/netdev/aac073de8beec3e531c86c101b274d434741c28e.camel@nvidia.com/
Reported-by: Cosmin Ratiu <cratiu@nvidia.com>
Tested-by: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250404161122.3907628-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-07 11:13:39 -07:00
Stanislav Fomichev
8965c160b8 net: use netif_disable_lro in ipv6_add_dev
ipv6_add_dev might call dev_disable_lro which unconditionally grabs
instance lock, so it will deadlock during NETDEV_REGISTER. Switch
to netif_disable_lro.

Make sure all callers hold the instance lock as well.

Cc: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250401163452.622454-4-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-03 15:32:08 -07:00
Stanislav Fomichev
4c975fd700 net: hold instance lock during NETDEV_REGISTER/UP
Callers of inetdev_init can come from several places with inconsistent
expectation about netdev instance lock. Grab instance lock during
REGISTER (plus UP). Also solve the inconsistency with UNREGISTER
where it was locked only during move netns path.

WARNING: CPU: 10 PID: 1479 at ./include/net/netdev_lock.h:54
__netdev_update_features+0x65f/0xca0
__warn+0x81/0x180
__netdev_update_features+0x65f/0xca0
report_bug+0x156/0x180
handle_bug+0x4f/0x90
exc_invalid_op+0x13/0x60
asm_exc_invalid_op+0x16/0x20
__netdev_update_features+0x65f/0xca0
netif_disable_lro+0x30/0x1d0
inetdev_init+0x12f/0x1f0
inetdev_event+0x48b/0x870
notifier_call_chain+0x38/0xf0
register_netdevice+0x741/0x8b0
register_netdev+0x1f/0x40
mlx5e_probe+0x4e3/0x8e0 [mlx5_core]
auxiliary_bus_probe+0x3f/0x90
really_probe+0xc3/0x3a0
__driver_probe_device+0x80/0x150
driver_probe_device+0x1f/0x90
__device_attach_driver+0x7d/0x100
bus_for_each_drv+0x80/0xd0
__device_attach+0xb4/0x1c0
bus_probe_device+0x91/0xa0
device_add+0x657/0x870

Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reported-by: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250401163452.622454-3-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-03 15:32:08 -07:00
Stanislav Fomichev
d996e412b2 bpf: add missing ops lock around dev_xdp_attach_link
Syzkaller points out that create_link path doesn't grab ops lock,
add it.

Reported-by: syzbot+08936936fe8132f91f1a@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/67e6b3e8.050a0220.2f068f.0079.GAE@google.com/
Fixes: 97246d6d21 ("net: hold netdev instance lock during ndo_bpf")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250331142814.1887506-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-02 16:06:15 -07:00
Linus Torvalds
1a9239bb42 Networking changes for 6.15.
Core & protocols
 ----------------
 
  - Continue Netlink conversions to per-namespace RTNL lock
    (IPv4 routing, routing rules, routing next hops, ARP ioctls).
 
  - Continue extending the use of netdev instance locks. As a driver
    opt-in protect queue operations and (in due course) ethtool
    operations with the instance lock and not RTNL lock.
 
  - Support collecting TCP timestamps (data submitted, sent, acked)
    in BPF, allowing for transparent (to the application) and lower
    overhead tracking of TCP RPC performance.
 
  - Tweak existing networking Rx zero-copy infra to support zero-copy
    Rx via io_uring.
 
  - Optimize MPTCP performance in single subflow mode by 29%.
 
  - Enable GRO on packets which went thru XDP CPU redirect (were queued
    for processing on a different CPU). Improving TCP stream performance
    up to 2x.
 
  - Improve performance of contended connect() by 200% by searching
    for an available 4-tuple under RCU rather than a spin lock.
    Bring an additional 229% improvement by tweaking hash distribution.
 
  - Avoid unconditionally touching sk_tsflags on RX, improving
    performance under UDP flood by as much as 10%.
 
  - Avoid skb_clone() dance in ping_rcv() to improve performance under
    ping flood.
 
  - Avoid FIB lookup in netfilter if socket is available, 20% perf win.
 
  - Rework network device creation (in-kernel) API to more clearly
    identify network namespaces and their roles.
    There are up to 4 namespace roles but we used to have just 2 netns
    pointer arguments, interpreted differently based on context.
 
  - Use sysfs_break_active_protection() instead of trylock to avoid
    deadlocks between unregistering objects and sysfs access.
 
  - Add a new sysctl and sockopt for capping max retransmit timeout
    in TCP.
 
  - Support masking port and DSCP in routing rule matches.
 
  - Support dumping IPv4 multicast addresses with RTM_GETMULTICAST.
 
  - Support specifying at what time packet should be sent on AF_XDP
    sockets.
 
  - Expose TCP ULP diagnostic info (for TLS and MPTCP) to non-admin users.
 
  - Add Netlink YAML spec for WiFi (nl80211) and conntrack.
 
  - Introduce EXPORT_IPV6_MOD() and EXPORT_IPV6_MOD_GPL() for symbols
    which only need to be exported when IPv6 support is built as a module.
 
  - Age FDB entries based on Rx not Tx traffic in VxLAN, similar
    to normal bridging.
 
  - Allow users to specify source port range for GENEVE tunnels.
 
  - netconsole: allow attaching kernel release, CPU ID and task name
    to messages as metadata
 
 Driver API
 ----------
 
  - Continue rework / fixing of Energy Efficient Ethernet (EEE) across
    the SW layers. Delegate the responsibilities to phylink where possible.
    Improve its handling in phylib.
 
  - Support symmetric OR-XOR RSS hashing algorithm.
 
  - Support tracking and preserving IRQ affinity by NAPI itself.
 
  - Support loopback mode speed selection for interface selftests.
 
 Device drivers
 --------------
 
  - Remove the IBM LCS driver for s390.
 
  - Remove the sb1000 cable modem driver.
 
  - Add support for SFP module access over SMBus.
 
  - Add MCTP transport driver for MCTP-over-USB.
 
  - Enable XDP metadata support in multiple drivers.
 
  - Ethernet high-speed NICs:
    - Broadcom (bnxt):
      - add PCIe TLP Processing Hints (TPH) support for new AMD platforms
      - support dumping RoCE queue state for debug
      - opt into instance locking
    - Intel (100G, ice, idpf):
      - ice: rework MSI-X IRQ management and distribution
      - ice: support for E830 devices
      - iavf: add support for Rx timestamping
      - iavf: opt into instance locking
    - nVidia/Mellanox:
      - mlx4: use page pool memory allocator for Rx
      - mlx5: support for one PTP device per hardware clock
      - mlx5: support for 200Gbps per-lane link modes
      - mlx5: move IPSec policy check after decryption
    - AMD/Solarflare:
      - support FW flashing via devlink
    - Cisco (enic):
      - use page pool memory allocator for Rx
      - enable 32, 64 byte CQEs
      - get max rx/tx ring size from the device
    - Meta (fbnic):
      - support flow steering and RSS configuration
      - report queue stats
      - support TCP segmentation
      - support IRQ coalescing
      - support ring size configuration
    - Marvell/Cavium:
      - support AF_XDP
    - Wangxun:
      - support for PTP clock and timestamping
    - Huawei (hibmcge):
      - checksum offload
      - add more statistics
 
  - Ethernet virtual:
    - VirtIO net:
      - aggressively suppress Tx completions, improve perf by 96% with
        1 CPU and 55% with 2 CPUs
      - expose NAPI to IRQ mapping and persist NAPI settings
    - Google (gve):
      - support XDP in DQO RDA Queue Format
      - opt into instance locking
    - Microsoft vNIC:
      - support BIG TCP
 
  - Ethernet NICs consumer, and embedded:
    - Synopsys (stmmac):
      - cleanup Tx and Tx clock setting and other link-focused cleanups
      - enable SGMII and 2500BASEX mode switching for Intel platforms
      - support Sophgo SG2044
    - Broadcom switches (b53):
      - support for BCM53101
    - TI:
      - iep: add perout configuration support
      - icssg: support XDP
    - Cadence (macb):
      - implement BQL
    - Xilinx (axinet):
      - support dynamic IRQ moderation and changing coalescing at runtime
      - implement BQL
      - report standard stats
    - MediaTek:
      - support phylink managed EEE
    - Intel:
      - igc: don't restart the interface on every XDP program change
    - RealTek (r8169):
      - support reading registers of internal PHYs directly
      - increase max jumbo packet size on RTL8125/RTL8126
    - Airoha:
      - support for RISC-V NPU packet processing unit
      - enable scatter-gather and support MTU up to 9kB
    - Tehuti (tn40xx):
      - support cards with TN4010 MAC and an Aquantia AQR105 PHY
 
  - Ethernet PHYs:
    - support for TJA1102S, TJA1121
    - dp83tg720: add randomized polling intervals for link detection
    - dp83822: support changing the transmit amplitude voltage
    - support for LEDs on 88q2xxx
 
  - CAN:
    - canxl: support Remote Request Substitution bit access
    - flexcan: add S32G2/S32G3 SoC
 
  - WiFi:
    - remove cooked monitor support
    - strict mode for better AP testing
    - basic EPCS support
    - OMI RX bandwidth reduction support
    - batman-adv: add support for jumbo frames
 
  - WiFi drivers:
    - RealTek (rtw88):
      - support RTL8814AE and RTL8814AU
    - RealTek (rtw89):
      - switch using wiphy_lock and wiphy_work
      - add BB context to manipulate two PHY as preparation of MLO
      - improve BT-coexistence mechanism to play A2DP smoothly
    - Intel (iwlwifi):
      - add new iwlmld sub-driver for latest HW/FW combinations
    - MediaTek (mt76):
      - preparation for mt7996 Multi-Link Operation (MLO) support
    - Qualcomm/Atheros (ath12k):
      - continued work on MLO
    - Silabs (wfx):
      - Wake-on-WLAN support
 
  - Bluetooth:
    - add support for skb TX SND/COMPLETION timestamping
    - hci_core: enable buffer flow control for SCO/eSCO
    - coredump: log devcd dumps into the monitor
 
  - Bluetooth drivers:
    - intel: add support to configure TX power
    - nxp: handle bootloader error during cmd5 and cmd7
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core & protocols:

   - Continue Netlink conversions to per-namespace RTNL lock
     (IPv4 routing, routing rules, routing next hops, ARP ioctls)

   - Continue extending the use of netdev instance locks. As a driver
     opt-in protect queue operations and (in due course) ethtool
     operations with the instance lock and not RTNL lock.

   - Support collecting TCP timestamps (data submitted, sent, acked) in
     BPF, allowing for transparent (to the application) and lower
     overhead tracking of TCP RPC performance.

   - Tweak existing networking Rx zero-copy infra to support zero-copy
     Rx via io_uring.

   - Optimize MPTCP performance in single subflow mode by 29%.

   - Enable GRO on packets which went thru XDP CPU redirect (were queued
     for processing on a different CPU). Improving TCP stream
     performance up to 2x.

   - Improve performance of contended connect() by 200% by searching for
     an available 4-tuple under RCU rather than a spin lock. Bring an
     additional 229% improvement by tweaking hash distribution.

   - Avoid unconditionally touching sk_tsflags on RX, improving
     performance under UDP flood by as much as 10%.

   - Avoid skb_clone() dance in ping_rcv() to improve performance under
     ping flood.

   - Avoid FIB lookup in netfilter if socket is available, 20% perf win.

   - Rework network device creation (in-kernel) API to more clearly
     identify network namespaces and their roles. There are up to 4
     namespace roles but we used to have just 2 netns pointer arguments,
     interpreted differently based on context.

   - Use sysfs_break_active_protection() instead of trylock to avoid
     deadlocks between unregistering objects and sysfs access.

   - Add a new sysctl and sockopt for capping max retransmit timeout in
     TCP.

   - Support masking port and DSCP in routing rule matches.

   - Support dumping IPv4 multicast addresses with RTM_GETMULTICAST.

   - Support specifying at what time packet should be sent on AF_XDP
     sockets.

   - Expose TCP ULP diagnostic info (for TLS and MPTCP) to non-admin
     users.

   - Add Netlink YAML spec for WiFi (nl80211) and conntrack.

   - Introduce EXPORT_IPV6_MOD() and EXPORT_IPV6_MOD_GPL() for symbols
     which only need to be exported when IPv6 support is built as a
     module.

   - Age FDB entries based on Rx not Tx traffic in VxLAN, similar to
     normal bridging.

   - Allow users to specify source port range for GENEVE tunnels.

   - netconsole: allow attaching kernel release, CPU ID and task name to
     messages as metadata

  Driver API:

   - Continue rework / fixing of Energy Efficient Ethernet (EEE) across
     the SW layers. Delegate the responsibilities to phylink where
     possible. Improve its handling in phylib.

   - Support symmetric OR-XOR RSS hashing algorithm.

   - Support tracking and preserving IRQ affinity by NAPI itself.

   - Support loopback mode speed selection for interface selftests.

  Device drivers:

   - Remove the IBM LCS driver for s390

   - Remove the sb1000 cable modem driver

   - Add support for SFP module access over SMBus

   - Add MCTP transport driver for MCTP-over-USB

   - Enable XDP metadata support in multiple drivers

   - Ethernet high-speed NICs:
      - Broadcom (bnxt):
         - add PCIe TLP Processing Hints (TPH) support for new AMD
           platforms
         - support dumping RoCE queue state for debug
         - opt into instance locking
      - Intel (100G, ice, idpf):
         - ice: rework MSI-X IRQ management and distribution
         - ice: support for E830 devices
         - iavf: add support for Rx timestamping
         - iavf: opt into instance locking
      - nVidia/Mellanox:
         - mlx4: use page pool memory allocator for Rx
         - mlx5: support for one PTP device per hardware clock
         - mlx5: support for 200Gbps per-lane link modes
         - mlx5: move IPSec policy check after decryption
      - AMD/Solarflare:
         - support FW flashing via devlink
      - Cisco (enic):
         - use page pool memory allocator for Rx
         - enable 32, 64 byte CQEs
         - get max rx/tx ring size from the device
      - Meta (fbnic):
         - support flow steering and RSS configuration
         - report queue stats
         - support TCP segmentation
         - support IRQ coalescing
         - support ring size configuration
      - Marvell/Cavium:
         - support AF_XDP
      - Wangxun:
         - support for PTP clock and timestamping
      - Huawei (hibmcge):
         - checksum offload
         - add more statistics

   - Ethernet virtual:
      - VirtIO net:
         - aggressively suppress Tx completions, improve perf by 96%
           with 1 CPU and 55% with 2 CPUs
         - expose NAPI to IRQ mapping and persist NAPI settings
      - Google (gve):
         - support XDP in DQO RDA Queue Format
         - opt into instance locking
      - Microsoft vNIC:
         - support BIG TCP

   - Ethernet NICs consumer, and embedded:
      - Synopsys (stmmac):
         - cleanup Tx and Tx clock setting and other link-focused
           cleanups
         - enable SGMII and 2500BASEX mode switching for Intel platforms
         - support Sophgo SG2044
      - Broadcom switches (b53):
         - support for BCM53101
      - TI:
         - iep: add perout configuration support
         - icssg: support XDP
      - Cadence (macb):
         - implement BQL
      - Xilinx (axinet):
         - support dynamic IRQ moderation and changing coalescing at
           runtime
         - implement BQL
         - report standard stats
      - MediaTek:
         - support phylink managed EEE
      - Intel:
         - igc: don't restart the interface on every XDP program change
      - RealTek (r8169):
         - support reading registers of internal PHYs directly
         - increase max jumbo packet size on RTL8125/RTL8126
      - Airoha:
         - support for RISC-V NPU packet processing unit
         - enable scatter-gather and support MTU up to 9kB
      - Tehuti (tn40xx):
         - support cards with TN4010 MAC and an Aquantia AQR105 PHY

   - Ethernet PHYs:
      - support for TJA1102S, TJA1121
      - dp83tg720: add randomized polling intervals for link detection
      - dp83822: support changing the transmit amplitude voltage
      - support for LEDs on 88q2xxx

   - CAN:
      - canxl: support Remote Request Substitution bit access
      - flexcan: add S32G2/S32G3 SoC

   - WiFi:
      - remove cooked monitor support
      - strict mode for better AP testing
      - basic EPCS support
      - OMI RX bandwidth reduction support
      - batman-adv: add support for jumbo frames

   - WiFi drivers:
      - RealTek (rtw88):
         - support RTL8814AE and RTL8814AU
      - RealTek (rtw89):
         - switch using wiphy_lock and wiphy_work
         - add BB context to manipulate two PHY as preparation of MLO
         - improve BT-coexistence mechanism to play A2DP smoothly
      - Intel (iwlwifi):
         - add new iwlmld sub-driver for latest HW/FW combinations
      - MediaTek (mt76):
         - preparation for mt7996 Multi-Link Operation (MLO) support
      - Qualcomm/Atheros (ath12k):
         - continued work on MLO
      - Silabs (wfx):
         - Wake-on-WLAN support

   - Bluetooth:
      - add support for skb TX SND/COMPLETION timestamping
      - hci_core: enable buffer flow control for SCO/eSCO
      - coredump: log devcd dumps into the monitor

   - Bluetooth drivers:
      - intel: add support to configure TX power
      - nxp: handle bootloader error during cmd5 and cmd7"

* tag 'net-next-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1681 commits)
  unix: fix up for "apparmor: add fine grained af_unix mediation"
  mctp: Fix incorrect tx flow invalidation condition in mctp-i2c
  net: usb: asix: ax88772: Increase phy_name size
  net: phy: Introduce PHY_ID_SIZE — minimum size for PHY ID string
  net: libwx: fix Tx L4 checksum
  net: libwx: fix Tx descriptor content for some tunnel packets
  atm: Fix NULL pointer dereference
  net: tn40xx: add pci-id of the aqr105-based Tehuti TN4010 cards
  net: tn40xx: prepare tn40xx driver to find phy of the TN9510 card
  net: tn40xx: create swnode for mdio and aqr105 phy and add to mdiobus
  net: phy: aquantia: add essential functions to aqr105 driver
  net: phy: aquantia: search for firmware-name in fwnode
  net: phy: aquantia: add probe function to aqr105 for firmware loading
  net: phy: Add swnode support to mdiobus_scan
  gve: add XDP DROP and PASS support for DQ
  gve: update XDP allocation path support RX buffer posting
  gve: merge packet buffer size fields
  gve: update GQ RX to use buf_size
  gve: introduce config-based allocation for XDP
  gve: remove xdp_xsk_done and xdp_xsk_wakeup statistics
  ...
2025-03-26 21:48:21 -07:00
Linus Torvalds
a50b4fe095 A treewide hrtimer timer cleanup
hrtimers are initialized with hrtimer_init() and a subsequent store to
   the callback pointer. This turned out to be suboptimal for the upcoming
   Rust integration and is obviously a silly implementation to begin with.
 
   This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
   with hrtimer_setup(T, cb);
 
   The conversion was done with Coccinelle and a few manual fixups.
 
   Once the conversion has completely landed in mainline, hrtimer_init()
   will be removed and the hrtimer::function becomes a private member.
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Merge tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer cleanups from Thomas Gleixner:
 "A treewide hrtimer timer cleanup

  hrtimers are initialized with hrtimer_init() and a subsequent store to
  the callback pointer. This turned out to be suboptimal for the
  upcoming Rust integration and is obviously a silly implementation to
  begin with.

  This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
  with hrtimer_setup(T, cb);

  The conversion was done with Coccinelle and a few manual fixups.

  Once the conversion has completely landed in mainline, hrtimer_init()
  will be removed and the hrtimer::function becomes a private member"

* tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits)
  wifi: rt2x00: Switch to use hrtimer_update_function()
  io_uring: Use helper function hrtimer_update_function()
  serial: xilinx_uartps: Use helper function hrtimer_update_function()
  ASoC: fsl: imx-pcm-fiq: Switch to use hrtimer_setup()
  RDMA: Switch to use hrtimer_setup()
  virtio: mem: Switch to use hrtimer_setup()
  drm/vmwgfx: Switch to use hrtimer_setup()
  drm/xe/oa: Switch to use hrtimer_setup()
  drm/vkms: Switch to use hrtimer_setup()
  drm/msm: Switch to use hrtimer_setup()
  drm/i915/request: Switch to use hrtimer_setup()
  drm/i915/uncore: Switch to use hrtimer_setup()
  drm/i915/pmu: Switch to use hrtimer_setup()
  drm/i915/perf: Switch to use hrtimer_setup()
  drm/i915/gvt: Switch to use hrtimer_setup()
  drm/i915/huc: Switch to use hrtimer_setup()
  drm/amdgpu: Switch to use hrtimer_setup()
  stm class: heartbeat: Switch to use hrtimer_setup()
  i2c: Switch to use hrtimer_setup()
  iio: Switch to use hrtimer_setup()
  ...
2025-03-25 10:54:15 -07:00
Jakub Kicinski
b52458652e net: protect rxq->mp_params with the instance lock
Ensure that all accesses to mp_params are under the netdev
instance lock. The only change we need is to move
dev_memory_provider_uninstall() under the lock.

Appropriately swap the asserts.

Reviewed-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250324224537.248800-8-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-25 10:06:49 -07:00
Jakub Kicinski
310ae9eb26 net: designate queue -> napi linking as "ops protected"
netdev netlink is the only reader of netdev_{,rx_}queue->napi,
and it already holds netdev->lock. Switch protection of
the writes to netdev->lock to "ops protected".

The expectation will be now that accessing queue->napi
will require netdev->lock for "ops locked" drivers, and
rtnl_lock for all other drivers.

Current "ops locked" drivers don't require any changes.
gve and netdevsim use _locked() helpers right next to
netif_queue_set_napi() so they must be holding the instance
lock. iavf doesn't call it. bnxt is a bit messy but all paths
seem locked.

Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250324224537.248800-7-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-25 10:06:49 -07:00
Jakub Kicinski
0a65dcf624 net: designate queue counts as "double ops protected" by instance lock
Drivers which opt into instance lock protection of ops should
only call set_real_num_*_queues() under the instance lock.
This means that queue counts are double protected (writes
are under both rtnl_lock and instance lock, readers under
either).

Some readers may still be under the rtnl_lock, however, so for
now we need double protection of writers.

OTOH queue API paths are only under the protection of the instance
lock, so we need to validate that the instance is actually locking
ops, otherwise the input checks we do against queue count are racy.

Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250324224537.248800-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-25 10:06:49 -07:00
Jakub Kicinski
bae2da8261 net: remove netif_set_real_num_rx_queues() helper for when SYSFS=n
Since commit a953be53ce ("net-sysfs: add support for device-specific
rx queue sysfs attributes"), so for at least a decade now it is safe
to call net_rx_queue_update_kobjects() when SYSFS=n. That function
does its own ifdef-inery and will return 0. Remove the unnecessary
stub for netif_set_real_num_rx_queues().

Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250324224537.248800-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-25 10:04:49 -07:00
Eric Dumazet
f3483c8e1d net: rfs: hash function change
RFS is using two kinds of hash tables.

First one is controlled by /proc/sys/net/core/rps_sock_flow_entries = 2^N
and using the N low order bits of the l4 hash is good enough.

Then each RX queue has its own hash table, controlled by
/sys/class/net/eth1/queues/rx-$q/rps_flow_cnt = 2^X

Current hash function, using the X low order bits is suboptimal,
because RSS is usually using Func(hash) = (hash % power_of_two);

For example, with 32 RX queues, 6 low order bits have no entropy
for a given queue.

Switch this hash function to hash_32(hash, log) to increase
chances to use all possible slots and reduce collisions.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250321171309.634100-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-25 08:24:13 -07:00
Paolo Abeni
c353e8983e net: introduce per netns packet chains
Currently network taps unbound to any interface are linked in the
global ptype_all list, affecting the performance in all the network
namespaces.

Add per netns ptypes chains, so that in the mentioned case only
the netns owning the packet socket(s) is affected.

While at that drop the global ptype_all list: no in kernel user
registers a tap on "any" type without specifying either the target
device or the target namespace (and IMHO doing that would not make
any sense).

Note that this adds a conditional in the fast path (to check for
per netns ptype_specific list) and increases the dataset size by
a cacheline (owing the per netns lists).

Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumaze@google.com>
Link: https://patch.msgid.link/ae405f98875ee87f8150c460ad162de7e466f8a7.1742494826.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-24 13:58:22 -07:00
Stanislav Fomichev
6dd132516f net: reorder dev_addr_sem lock
Lockdep complains about circular lock in 1 -> 2 -> 3 (see below).

Change the lock ordering to be:
- rtnl_lock
- dev_addr_sem
- netdev_ops (only for lower devices!)
- team_lock (or other per-upper device lock)

1. rtnl_lock -> netdev_ops -> dev_addr_sem

rtnl_setlink
  rtnl_lock
    do_setlink IFLA_ADDRESS on lower
      netdev_ops
        dev_addr_sem

2. rtnl_lock -> team_lock -> netdev_ops

rtnl_newlink
  rtnl_lock
    do_setlink IFLA_MASTER on lower
      do_set_master
        team_add_slave
          team_lock
            team_port_add
	      dev_set_mtu
	        netdev_ops

3. rtnl_lock -> dev_addr_sem -> team_lock

rtnl_newlink
  rtnl_lock
    do_setlink IFLA_ADDRESS on upper
      dev_addr_sem
        netif_set_mac_address
          team_set_mac_address
            team_lock

4. rtnl_lock -> netdev_ops -> dev_addr_sem

rtnl_lock
  dev_ifsioc
    dev_set_mac_address_user

__tun_chr_ioctl
  rtnl_lock
    dev_set_mac_address_user

tap_ioctl
  rtnl_lock
    dev_set_mac_address_user

dev_set_mac_address_user
  netdev_lock_ops
    netif_set_mac_address_user
      dev_addr_sem

v2:
- move lock reorder to happen after kmalloc (Kuniyuki)

Cc: Kohei Enju <enjuk@amazon.com>
Fixes: df43d8bf10 ("net: replace dev_addr_sem with netdev instance lock")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250312190513.1252045-3-sdf@fomichev.me
Tested-by: Lei Yang <leiyang@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-19 18:52:00 +01:00
Stanislav Fomichev
8033d2aef5 Revert "net: replace dev_addr_sem with netdev instance lock"
This reverts commit df43d8bf10.

Cc: Kohei Enju <enjuk@amazon.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Fixes: df43d8bf10 ("net: replace dev_addr_sem with netdev instance lock")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250312190513.1252045-2-sdf@fomichev.me
Tested-by: Lei Yang <leiyang@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-19 18:52:00 +01:00
Paolo Abeni
941defcea7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.14-rc6).

Conflicts:

tools/testing/selftests/drivers/net/ping.py
  75cc19c8ff ("selftests: drv-net: add xdp cases for ping.py")
  de94e86974 ("selftests: drv-net: store addresses in dict indexed by ipver")
https://lore.kernel.org/netdev/20250311115758.17a1d414@canb.auug.org.au/

net/core/devmem.c
  a70f891e0f ("net: devmem: do not WARN conditionally after netdev_rx_queue_restart()")
  1d22d3060b ("net: drop rtnl_lock for queue_mgmt operations")
https://lore.kernel.org/netdev/20250313114929.43744df1@canb.auug.org.au/

Adjacent changes:

tools/testing/selftests/net/Makefile
  6f50175cca ("selftests: Add IPv6 link-local address generation tests for GRE devices.")
  2e5584e0f9 ("selftests/net: expand cmsg_ipv6.sh with ipv4")

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  661958552e ("eth: bnxt: do not use BNXT_VNIC_NTUPLE unconditionally in queue restart logic")
  fe96d717d3 ("bnxt_en: Extend queue stop/start for TX rings")

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-13 23:08:11 +01:00
Stanislav Fomichev
110eff172d eth: bnxt: switch to netif_close
All (error) paths that call dev_close are already holding instance lock,
so switch to netif_close to avoid the deadlock.

v2:
- add missing EXPORT_MODULE for netif_close

Fixes: 004b500801 ("eth: bnxt: remove most dependencies on RTNL")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250309215851.2003708-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-12 13:19:15 -07:00
Stanislav Fomichev
0a13c1e0a4 net: revert to lockless TC_SETUP_BLOCK and TC_SETUP_FT
There is a couple of places from which we can arrive to ndo_setup_tc
with TC_SETUP_BLOCK/TC_SETUP_FT:
- netlink
- netlink notifier
- netdev notifier

Locking netdev too deep in this call chain seems to be problematic
(especially assuming some/all of the call_netdevice_notifiers
NETDEV_UNREGISTER) might soon be running with the instance lock).
Revert to lockless ndo_setup_tc for TC_SETUP_BLOCK/TC_SETUP_FT. NFT
framework already takes care of most of the locking. Document
the assumptions.

ndo_setup_tc TC_SETUP_BLOCK
  nft_block_offload_cmd
    nft_chain_offload_cmd
      nft_flow_block_chain
        nft_flow_offload_chain
	  nft_flow_rule_offload_abort
	    nft_flow_rule_offload_commit
	  nft_flow_rule_offload_commit
	    nf_tables_commit
	      nfnetlink_rcv_batch
	        nfnetlink_rcv_skb_batch
		  nfnetlink_rcv
	nft_offload_netdev_event
	  NETDEV_UNREGISTER notifier

ndo_setup_tc TC_SETUP_FT
  nf_flow_table_offload_cmd
    nf_flow_table_offload_setup
      nft_unregister_flowtable_hook
        nft_register_flowtable_net_hooks
	  nft_flowtable_update
	  nf_tables_newflowtable
	    nfnetlink_rcv_batch (.call NFNL_CB_BATCH)
	nft_flowtable_update
	  nf_tables_newflowtable
	nft_flowtable_event
	  nf_tables_flowtable_event
	    NETDEV_UNREGISTER notifier
      __nft_unregister_flowtable_net_hooks
        nft_unregister_flowtable_net_hooks
	  nf_tables_commit
	    nfnetlink_rcv_batch (.call NFNL_CB_BATCH)
	  __nf_tables_abort
	    nf_tables_abort
	      nfnetlink_rcv_batch
	__nft_release_hook
	  __nft_release_hooks
	    nf_tables_pre_exit_net -> module unload
	  nft_rcv_nl_event
	    netlink_register_notifier (oh boy)
      nft_register_flowtable_net_hooks
      	nft_flowtable_update
	  nf_tables_newflowtable
        nf_tables_newflowtable

Fixes: c4f0f30b42 ("net: hold netdev instance lock during nft ndo_setup_tc")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Reported-by: syzbot+0afb4bcf91e5a1afdcad@syzkaller.appspotmail.com
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250308044726.1193222-1-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-12 13:02:00 -07:00
Jakub Kicinski
8ef890df40 net: move misc netdev_lock flavors to a separate header
Move the more esoteric helpers for netdev instance lock to
a dedicated header. This avoids growing netdevice.h to infinity
and makes rebuilding the kernel much faster (after touching
the header with the helpers).

The main netdev_lock() / netdev_unlock() functions are used
in static inlines in netdevice.h and will probably be used
most commonly, so keep them in netdevice.h.

Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250307183006.2312761-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-08 09:06:50 -08:00
Mina Almasry
f3600c867c netmem: prevent TX of unreadable skbs
Currently on stable trees we have support for netmem/devmem RX but not
TX. It is not safe to forward/redirect an RX unreadable netmem packet
into the device's TX path, as the device may call dma-mapping APIs on
dma addrs that should not be passed to it.

Fix this by preventing the xmit of unreadable skbs.

Tested by configuring tc redirect:

sudo tc qdisc add dev eth1 ingress
sudo tc filter add dev eth1 ingress protocol ip prio 1 flower ip_proto \
	tcp src_ip 192.168.1.12 action mirred egress redirect dev eth1

Before, I see unreadable skbs in the driver's TX path passed to dma
mapping APIs.

After, I don't see unreadable skbs in the driver's TX path passed to dma
mapping APIs.

Fixes: 65249feb6b ("net: add support for skbs with unreadable frags")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20250306215520.1415465-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-07 19:32:25 -08:00
Stanislav Fomichev
df43d8bf10 net: replace dev_addr_sem with netdev instance lock
Lockdep reports possible circular dependency in [0]. Instead of
fixing the ordering, replace global dev_addr_sem with netdev
instance lock. Most of the paths that set/get mac are RTNL
protected. Two places where it's not, convert to explicit
locking:
- sysfs address_show
- dev_get_mac_address via dev_ioctl

0: https://netdev-3.bots.linux.dev/vmksft-forwarding-dbg/results/993321/24-router-bridge-1d-lag-sh/stderr

Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-12-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-06 12:59:45 -08:00
Stanislav Fomichev
97246d6d21 net: hold netdev instance lock during ndo_bpf
Cover the paths that come via bpf system call and XSK bind.

Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-10-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-06 12:59:44 -08:00
Stanislav Fomichev
ad7c7b2172 net: hold netdev instance lock during sysfs operations
Most of them are already covered by the converted dev_xxx APIs.
Add the locking wrappers for the remaining ones.

Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-9-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-06 12:59:44 -08:00
Stanislav Fomichev
ffb7ed19ac net: hold netdev instance lock during ioctl operations
Convert all ndo_eth_ioctl invocations to dev_eth_ioctl which does the
locking. Reflow some of the dev_siocxxx to drop else clause.

Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-8-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-06 12:59:44 -08:00
Stanislav Fomichev
7e4d784f58 net: hold netdev instance lock during rtnetlink operations
To preserve the atomicity, hold the lock while applying multiple
attributes. The major issue with a full conversion to the instance
lock are software nesting devices (bonding/team/vrf/etc). Those
devices call into the core stack for their lower (potentially
real hw) devices. To avoid explicitly wrapping all those places
into instance lock/unlock, introduce new API boundaries:

- (some) existing dev_xxx calls are now considered "external"
  (to drivers) APIs and they transparently grab the instance
  lock if needed (dev_api.c)
- new netif_xxx calls are internal core stack API (naming is
  sketchy, I've tried netdev_xxx_locked per Jakub's suggestion,
  but it feels a bit verbose; but happy to get back to this
  naming scheme if this is the preference)

This avoids touching most of the existing ioctl/sysfs/drivers paths.

Note the special handling of ndo_xxx_slave operations: I exploit
the fact that none of the drivers that call these functions
need/use instance lock. At the same time, they use dev_xxx
APIs, so the lower device has to be unlocked.

Changes in unregister_netdevice_many_notify (to protect dev->state
with instance lock) trigger lockdep - the loop over close_list
(mostly from cleanup_net) introduces spurious ordering issues.
netdev_lock_cmp_fn has a justification on why it's ok to suppress
for now.

Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-7-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-06 12:59:44 -08:00
Stanislav Fomichev
c4f0f30b42 net: hold netdev instance lock during nft ndo_setup_tc
Introduce new dev_setup_tc for nft ndo_setup_tc paths.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-3-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-06 12:59:43 -08:00
Stanislav Fomichev
d4c22ec680 net: hold netdev instance lock during ndo_open/ndo_stop
For the drivers that use shaper API, switch to the mode where
core stack holds the netdev lock. This affects two drivers:

* iavf - already grabs netdev lock in ndo_open/ndo_stop, so mostly
         remove these
* netdevsim - switch to _locked APIs to avoid deadlock

iavf_close diff is a bit confusing, the existing call looks like this:
  iavf_close() {
    netdev_lock()
    ..
    netdev_unlock()
    wait_event_timeout(down_waitqueue)
  }

I change it to the following:
  netdev_lock()
  iavf_close() {
    ..
    netdev_unlock()
    wait_event_timeout(down_waitqueue)
    netdev_lock() // reusing this lock call
  }
  netdev_unlock()

Since I'm reusing existing netdev_lock call, so it looks like I only
add netdev_unlock.

Cc: Saeed Mahameed <saeed@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-2-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-06 12:59:43 -08:00
Dan Carpenter
f252f23ab6 net: Prevent use after free in netif_napi_set_irq_locked()
The cpu_rmap_put() will call kfree() when the last reference is dropped
so it could result in a use after free when we dereference the same
pointer the next line.  Move the cpu_rmap_put() after the dereference.

Fixes: bd7c00605e ("net: move aRFS rmap management and CPU affinity to core")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/5a9c53a4-5487-4b8c-9ffa-d8e5343aaaaf@stanley.mountain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-04 18:33:24 -08:00
Nicolas Dichtel
12b6f7069b net: plumb extack in __dev_change_net_namespace()
It could be hard to understand why the netlink command fails. For example,
if dev->netns_immutable is set, the error is "Invalid argument".

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-04 12:44:48 +01:00
Nicolas Dichtel
0c493da863 net: rename netns_local to netns_immutable
The name 'netns_local' is confusing. A following commit will export it via
netlink, so let's use a more explicit name.

Reported-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-04 12:44:48 +01:00
Jakub Kicinski
357660d759 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.14-rc5).

Conflicts:

drivers/net/ethernet/cadence/macb_main.c
  fa52f15c74 ("net: cadence: macb: Synchronize stats calculations")
  75696dd0fd ("net: cadence: macb: Convert to get_stats64")
https://lore.kernel.org/20250224125848.68ee63e5@canb.auug.org.au

Adjacent changes:

drivers/net/ethernet/intel/ice/ice_sriov.c
  79990cf5e7 ("ice: Fix deinitializing VF in error path")
  a203163274 ("ice: simplify VF MSI-X managing")

net/ipv4/tcp.c
  18912c5206 ("tcp: devmem: don't write truncated dmabuf CMSGs to userspace")
  297d389e9e ("net: prefix devmem specific helpers")

net/mptcp/subflow.c
  8668860b0a ("mptcp: reset when MPTCP opts are dropped after join")
  c3349a22c2 ("mptcp: consolidate subflow cleanup")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-27 10:20:58 -08:00
Alexander Lobakin
388d31417c net: gro: expose GRO init/cleanup to use outside of NAPI
Make GRO init and cleanup functions global to be able to use GRO
without a NAPI instance. Taking into account already global gro_flush(),
it's now fully usable standalone.
New functions are not exported, since they're not supposed to be used
outside of the kernel core code.

Tested-by: Daniel Xu <dxu@dxuuu.xyz>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-27 14:03:14 +01:00
Alexander Lobakin
291515c764 net: gro: decouple GRO from the NAPI layer
In fact, these two are not tied closely to each other. The only
requirements to GRO are to use it in the BH context and have some
sane limits on the packet batches, e.g. NAPI has a limit of its
budget (64/8/etc.).
Move purely GRO fields into a new structure, &gro_node. Embed it
into &napi_struct and adjust all the references.
gro_node::cached_napi_id is effectively the same as
napi_struct::napi_id, but to be used on GRO hotpath to mark skbs.
napi_struct::napi_id is now a fully control path field.

Three Ethernet drivers use napi_gro_flush() not really meant to be
exported, so move it to <net/gro.h> and add that include there.
napi_gro_receive() is used in more than 100 drivers, keep it
in <linux/netdevice.h>.
This does not make GRO ready to use outside of the NAPI context
yet.

Tested-by: Daniel Xu <dxu@dxuuu.xyz>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-27 14:03:14 +01:00
Ahmed Zaki
bd7c00605e net: move aRFS rmap management and CPU affinity to core
A common task for most drivers is to remember the user-set CPU affinity
to its IRQs. On each netdev reset, the driver should re-assign the user's
settings to the IRQs. Unify this task across all drivers by moving the CPU
affinity to napi->config.

However, to move the CPU affinity to core, we also need to move aRFS
rmap management since aRFS uses its own IRQ notifiers.

For the aRFS, add a new netdev flag "rx_cpu_rmap_auto". Drivers supporting
aRFS should set the flag via netif_enable_cpu_rmap() and core will allocate
and manage the aRFS rmaps. Freeing the rmap is also done by core when the
netdev is freed. For better IRQ affinity management, move the IRQ rmap
notifier inside the napi_struct and add new notify.notify and
notify.release functions: netif_irq_cpu_rmap_notify() and
netif_napi_affinity_release().

Now we have the aRFS rmap management in core, add CPU affinity mask to
napi_config. To delegate the CPU affinity management to the core, drivers
must:
 1 - set the new netdev flag "irq_affinity_auto":
                                       netif_enable_irq_affinity(netdev)
 2 - create the napi with persistent config:
                                       netif_napi_add_config()
 3 - bind an IRQ to the napi instance: netif_napi_set_irq()

the core will then make sure to use re-assign affinity to the napi's
IRQ.

The default IRQ mask is set to one cpu starting from the closest NUMA.

Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
Link: https://patch.msgid.link/20250224232228.990783-2-ahmed.zaki@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-26 19:51:37 -08:00
Frederic Weisbecker
77e45145e3 net: Handle napi_schedule() calls from non-interrupt
napi_schedule() is expected to be called either:

* From an interrupt, where raised softirqs are handled on IRQ exit

* From a softirq disabled section, where raised softirqs are handled on
  the next call to local_bh_enable().

* From a softirq handler, where raised softirqs are handled on the next
  round in do_softirq(), or further deferred to a dedicated kthread.

Other bare tasks context may end up ignoring the raised NET_RX vector
until the next random softirq handling opportunity, which may not
happen before a while if the CPU goes idle afterwards with the tick
stopped.

Such "misuses" have been detected on several places thanks to messages
of the kind:

	"NOHZ tick-stop error: local softirq work is pending, handler #08!!!"

For example:

       __raise_softirq_irqoff
        __napi_schedule
        rtl8152_runtime_resume.isra.0
        rtl8152_resume
        usb_resume_interface.isra.0
        usb_resume_both
        __rpm_callback
        rpm_callback
        rpm_resume
        __pm_runtime_resume
        usb_autoresume_device
        usb_remote_wakeup
        hub_event
        process_one_work
        worker_thread
        kthread
        ret_from_fork
        ret_from_fork_asm

And also:

* drivers/net/usb/r8152.c::rtl_work_func_t
* drivers/net/netdevsim/netdev.c::nsim_start_xmit

There is a long history of issues of this kind:

	019edd01d1 ("ath10k: sdio: Add missing BH locking around napi_schdule()")
	3300685893 ("idpf: disable local BH when scheduling napi for marker packets")
	e3d5d70cb4 ("net: lan78xx: fix "softirq work is pending" error")
	e55c27ed9c ("mt76: mt7615: add missing bh-disable around rx napi schedule")
	c0182aa985 ("mt76: mt7915: add missing bh-disable around tx napi enable/schedule")
	970be1dff2 ("mt76: disable BH around napi_schedule() calls")
	019edd01d1 ("ath10k: sdio: Add missing BH locking around napi_schdule()")
	30bfec4fec ("can: rx-offload: can_rx_offload_threaded_irq_finish(): add new  function to be called from threaded interrupt")
	e63052a5dd ("mlx5e: add add missing BH locking around napi_schdule()")
	83a0c6e589 ("i40e: Invoke softirqs after napi_reschedule")
	bd4ce941c8 ("mlx4: Invoke softirqs after napi_reschedule")
	8cf699ec84 ("mlx4: do not call napi_schedule() without care")
	ec13ee8014 ("virtio_net: invoke softirqs after __napi_schedule")

This shows that relying on the caller to arrange a proper context for
the softirqs to be handled while calling napi_schedule() is very fragile
and error prone. Also fixing them can also prove challenging if the
caller may be called from different kinds of contexts.

Therefore fix this from napi_schedule() itself with waking up ksoftirqd
when softirqs are raised from task contexts.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reported-by: Jakub Kicinski <kuba@kernel.org>
Reported-by: Francois Romieu <romieu@fr.zoreil.com>
Closes: https://lore.kernel.org/lkml/354a2690-9bbf-4ccb-8769-fa94707a9340@molgen.mpg.de/
Cc: Breno Leitao <leitao@debian.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250223221708.27130-1-frederic@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-26 18:56:55 -08:00
Kuniyuki Iwashima
01c9c123db net: Use rtnl_net_dev_lock() in register_netdevice_notifier_dev_net().
Breno Leitao reported the splat below. [0]

Commit 65161fb544 ("net: Fix dev_net(dev) race in
unregister_netdevice_notifier_dev_net().") added the
DEBUG_NET_WARN_ON_ONCE(), assuming that the netdev is not
registered before register_netdevice_notifier_dev_net().

But the assumption was simply wrong.

Let's use rtnl_net_dev_lock() in register_netdevice_notifier_dev_net().

[0]:
WARNING: CPU: 25 PID: 849 at net/core/dev.c:2150 register_netdevice_notifier_dev_net (net/core/dev.c:2150)
 <TASK>
 ? __warn (kernel/panic.c:242 kernel/panic.c:748)
 ? register_netdevice_notifier_dev_net (net/core/dev.c:2150)
 ? register_netdevice_notifier_dev_net (net/core/dev.c:2150)
 ? report_bug (lib/bug.c:? lib/bug.c:219)
 ? handle_bug (arch/x86/kernel/traps.c:285)
 ? exc_invalid_op (arch/x86/kernel/traps.c:309)
 ? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
 ? register_netdevice_notifier_dev_net (net/core/dev.c:2150)
 ? register_netdevice_notifier_dev_net (./include/net/net_namespace.h:406 ./include/linux/netdevice.h:2663 net/core/dev.c:2144)
 mlx5e_mdev_notifier_event+0x9f/0xf0 mlx5_ib
 notifier_call_chain.llvm.12241336988804114627 (kernel/notifier.c:85)
 blocking_notifier_call_chain (kernel/notifier.c:380)
 mlx5_core_uplink_netdev_event_replay (drivers/net/ethernet/mellanox/mlx5/core/main.c:352)
 mlx5_ib_roce_init.llvm.12447516292400117075+0x1c6/0x550 mlx5_ib
 mlx5r_probe+0x375/0x6a0 mlx5_ib
 ? kernfs_put (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-arch-fallback.h:2278 ./include/linux/atomic/atomic-instrumented.h:1384 fs/kernfs/dir.c:557)
 ? auxiliary_match_id (drivers/base/auxiliary.c:174)
 ? mlx5r_mp_remove+0x160/0x160 mlx5_ib
 really_probe (drivers/base/dd.c:? drivers/base/dd.c:658)
 driver_probe_device (drivers/base/dd.c:830)
 __driver_attach (drivers/base/dd.c:1217)
 bus_for_each_dev (drivers/base/bus.c:369)
 ? driver_attach (drivers/base/dd.c:1157)
 bus_add_driver (drivers/base/bus.c:679)
 driver_register (drivers/base/driver.c:249)

Fixes: 7fb1073300 ("net: Hold rtnl_net_lock() in (un)?register_netdevice_notifier_dev_net().")
Reported-by: Breno Leitao <leitao@debian.org>
Closes: https://lore.kernel.org/netdev/20250224-noisy-cordial-roadrunner-fad40c@leitao/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Tested-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20250225211023.96448-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-26 17:34:36 -08:00
Breno Leitao
7183877d68 net: Remove shadow variable in netdev_run_todo()
Fix a shadow variable warning in net/core/dev.c when compiled with
CONFIG_LOCKDEP enabled. The warning occurs because 'dev' is redeclared
inside the while loop, shadowing the outer scope declaration.

	net/core/dev.c:11211:22: warning: declaration shadows a local variable [-Wshadow]
		struct net_device *dev = list_first_entry(&unlink_list,

	net/core/dev.c:11202:21: note: previous declaration is here
		struct net_device *dev, *tmp;

Remove the redundant declaration since the variable is already defined
in the outer scope and will be overwritten in the subsequent
list_for_each_entry_safe() loop anyway.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250221-netcons_fix_shadow-v1-1-dee20c8658dd@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-24 14:34:54 -08:00
Jakub Kicinski
e87700965a bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Martin KaFai Lau says:

====================
pull-request: bpf-next 2025-02-20

We've added 19 non-merge commits during the last 8 day(s) which contain
a total of 35 files changed, 1126 insertions(+), 53 deletions(-).

The main changes are:

1) Add TCP_RTO_MAX_MS support to bpf_set/getsockopt, from Jason Xing

2) Add network TX timestamping support to BPF sock_ops, from Jason Xing

3) Add TX metadata Launch Time support, from Song Yoong Siang

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
  igc: Add launch time support to XDP ZC
  igc: Refactor empty frame insertion for launch time support
  net: stmmac: Add launch time support to XDP ZC
  selftests/bpf: Add launch time request to xdp_hw_metadata
  xsk: Add launch time hardware offload support to XDP Tx metadata
  selftests/bpf: Add simple bpf tests in the tx path for timestamping feature
  bpf: Support selective sampling for bpf timestamping
  bpf: Add BPF_SOCK_OPS_TSTAMP_SENDMSG_CB callback
  bpf: Add BPF_SOCK_OPS_TSTAMP_ACK_CB callback
  bpf: Add BPF_SOCK_OPS_TSTAMP_SND_HW_CB callback
  bpf: Add BPF_SOCK_OPS_TSTAMP_SND_SW_CB callback
  bpf: Add BPF_SOCK_OPS_TSTAMP_SCHED_CB callback
  net-timestamp: Prepare for isolating two modes of SO_TIMESTAMPING
  bpf: Disable unsafe helpers in TX timestamping callbacks
  bpf: Prevent unsafe access to the sock fields in the BPF timestamping callback
  bpf: Prepare the sock_ops ctx and call bpf prog for TX timestamping
  bpf: Add networking timestamping support to bpf_get/setsockopt()
  selftests/bpf: Add rto max for bpf_setsockopt test
  bpf: Support TCP_RTO_MAX_MS for bpf_setsockopt
====================

Link: https://patch.msgid.link/20250221022104.386462-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-21 15:59:47 -08:00
Jason Xing
6b98ec7e88 bpf: Add BPF_SOCK_OPS_TSTAMP_SCHED_CB callback
Support SCM_TSTAMP_SCHED case for bpf timestamping.

Add a new sock_ops callback, BPF_SOCK_OPS_TSTAMP_SCHED_CB. This
callback will occur at the same timestamping point as the user
space's SCM_TSTAMP_SCHED. The BPF program can use it to get the
same SCM_TSTAMP_SCHED timestamp without modifying the user-space
application.

A new SKBTX_BPF flag is added to mark skb_shinfo(skb)->tx_flags,
ensuring that the new BPF timestamping and the current user
space's SO_TIMESTAMPING do not interfere with each other.

Signed-off-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250220072940.99994-7-kerneljasonxing@gmail.com
2025-02-20 14:29:24 -08:00
Jakub Kicinski
5d6ba5ab85 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.14-rc4).

No conflicts or adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-20 10:37:30 -08:00
Paolo Abeni
6bc7e4eb04 Revert "net: skb: introduce and use a single page frag cache"
After the previous commit is finally safe to revert commit dbae2b0628
("net: skb: introduce and use a single page frag cache"): do it here.

The intended goal of such change was to counter a performance regression
introduced by commit 3226b158e6 ("net: avoid 32 x truesize
under-estimation for tiny skbs").

Unfortunately, the blamed commit introduces another regression for the
virtio_net driver. Such a driver calls napi_alloc_skb() with a tiny
size, so that the whole head frag could fit a 512-byte block.

The single page frag cache uses a 1K fragment for such allocation, and
the additional overhead, under small UDP packets flood, makes the page
allocator a bottleneck.

Thanks to commit bf9f1baa27 ("net: add dedicated kmem_cache for
typical/small skb->head"), this revert does not re-introduce the
original regression. Actually, in the relevant test on top of this
revert, I measure a small but noticeable positive delta, just above
noise level.

The revert itself required some additional mangling due to recent updates
in the affected code.

Suggested-by: Eric Dumazet <edumazet@google.com>
Fixes: dbae2b0628 ("net: skb: introduce and use a single page frag cache")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-20 10:53:25 +01:00
Breno Leitao
4b5a28b38c net: Add non-RCU dev_getbyhwaddr() helper
Add dedicated helper for finding devices by hardware address when
holding rtnl_lock, similar to existing dev_getbyhwaddr_rcu(). This prevents
PROVE_LOCKING warnings when rtnl_lock is held but RCU read lock is not.

Extract common address comparison logic into dev_addr_cmp().

The context about this change could be found in the following
discussion:

Link: https://lore.kernel.org/all/20250206-scarlet-ermine-of-improvement-1fcac5@leitao/

Cc: kuniyu@amazon.com
Cc: ushankar@purestorage.com
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250218-arm_fix_selftest-v5-1-d3d6892db9e1@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-19 18:59:29 -08:00
Kuniyuki Iwashima
d4c6bfc839 dev: Use rtnl_net_dev_lock() in unregister_netdev().
The following sequence is basically illegal when dev was fetched
without lookup because dev_net(dev) might be different after holding
rtnl_net_lock():

  net = dev_net(dev);
  rtnl_net_lock(net);

Let's use rtnl_net_dev_lock() in unregister_netdev().

Note that there is no real bug in unregister_netdev() for now
because RTNL protects the scope even if dev_net(dev) is changed
before/after RTNL.

Fixes: 00fb982393 ("dev: Hold per-netns RTNL in (un)?register_netdev().")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250217191129.19967-4-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-18 18:33:30 -08:00
Kuniyuki Iwashima
65161fb544 net: Fix dev_net(dev) race in unregister_netdevice_notifier_dev_net().
After the cited commit, dev_net(dev) is fetched before holding RTNL
and passed to __unregister_netdevice_notifier_net().

However, dev_net(dev) might be different after holding RTNL.

In the reported case [0], while removing a VF device, its netns was
being dismantled and the VF was moved to init_net.

So the following sequence is basically illegal when dev was fetched
without lookup:

  net = dev_net(dev);
  rtnl_net_lock(net);

Let's use a new helper rtnl_net_dev_lock() to fix the race.

It fetches dev_net_rcu(dev), bumps its net->passive, and checks if
dev_net_rcu(dev) is changed after rtnl_net_lock().

[0]:
BUG: KASAN: slab-use-after-free in notifier_call_chain (kernel/notifier.c:75 (discriminator 2))
Read of size 8 at addr ffff88810cefb4c8 by task test-bridge-lag/21127
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl (lib/dump_stack.c:123)
 print_report (mm/kasan/report.c:379 mm/kasan/report.c:489)
 kasan_report (mm/kasan/report.c:604)
 notifier_call_chain (kernel/notifier.c:75 (discriminator 2))
 call_netdevice_notifiers_info (net/core/dev.c:2011)
 unregister_netdevice_many_notify (net/core/dev.c:11551)
 unregister_netdevice_queue (net/core/dev.c:11487)
 unregister_netdev (net/core/dev.c:11635)
 mlx5e_remove (drivers/net/ethernet/mellanox/mlx5/core/en_main.c:6552 drivers/net/ethernet/mellanox/mlx5/core/en_main.c:6579) mlx5_core
 auxiliary_bus_remove (drivers/base/auxiliary.c:230)
 device_release_driver_internal (drivers/base/dd.c:1275 drivers/base/dd.c:1296)
 bus_remove_device (./include/linux/kobject.h:193 drivers/base/base.h:73 drivers/base/bus.c:583)
 device_del (drivers/base/power/power.h:142 drivers/base/core.c:3855)
 mlx5_rescan_drivers_locked (./include/linux/auxiliary_bus.h:241 drivers/net/ethernet/mellanox/mlx5/core/dev.c:333 drivers/net/ethernet/mellanox/mlx5/core/dev.c:535 drivers/net/ethernet/mellanox/mlx5/core/dev.c:549) mlx5_core
 mlx5_unregister_device (drivers/net/ethernet/mellanox/mlx5/core/dev.c:468) mlx5_core
 mlx5_uninit_one (./include/linux/instrumented.h:68 ./include/asm-generic/bitops/instrumented-non-atomic.h:141 drivers/net/ethernet/mellanox/mlx5/core/main.c:1563) mlx5_core
 remove_one (drivers/net/ethernet/mellanox/mlx5/core/main.c:965 drivers/net/ethernet/mellanox/mlx5/core/main.c:2019) mlx5_core
 pci_device_remove (./include/linux/pm_runtime.h:129 drivers/pci/pci-driver.c:475)
 device_release_driver_internal (drivers/base/dd.c:1275 drivers/base/dd.c:1296)
 unbind_store (drivers/base/bus.c:245)
 kernfs_fop_write_iter (fs/kernfs/file.c:338)
 vfs_write (fs/read_write.c:587 (discriminator 1) fs/read_write.c:679 (discriminator 1))
 ksys_write (fs/read_write.c:732)
 do_syscall_64 (arch/x86/entry/common.c:52 (discriminator 1) arch/x86/entry/common.c:83 (discriminator 1))
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
RIP: 0033:0x7f6a4d5018b7

Fixes: 7fb1073300 ("net: Hold rtnl_net_lock() in (un)?register_netdevice_notifier_dev_net().")
Reported-by: Yael Chemla <ychemla@nvidia.com>
Closes: https://lore.kernel.org/netdev/146eabfe-123c-4970-901e-e961b4c09bc3@nvidia.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250217191129.19967-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-18 18:33:30 -08:00
Breno Leitao
8f02c48f8f net: Remove redundant variable declaration in __dev_change_flags()
The old_flags variable is declared twice in __dev_change_flags(),
causing a shadow variable warning. This patch fixes the issue by
removing the redundant declaration, reusing the existing old_flags
variable instead.

	net/core/dev.c:9225:16: warning: declaration shadows a local variable [-Wshadow]
	9225 |                 unsigned int old_flags = dev->flags;
	|                              ^
	net/core/dev.c:9185:15: note: previous declaration is here
	9185 |         unsigned int old_flags = dev->flags;
	|                      ^
	1 warning generated.

Remove the redundant inner declaration and reuse the existing old_flags
variable since its value is not needed outside the if block, and it is
safe to reuse the variable. This eliminates the warning while
maintaining the same functionality.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20250217-old_flags-v2-1-4cda3b43a35f@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-18 18:10:56 -08:00