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Vlad Buslov 8e93f29422 net/mlx5: Disable irq when locking lag_lock
The lag_lock is taken from both process and softirq contexts which results
lockdep warning[0] about potential deadlock. However, just disabling
softirqs by using *_bh spinlock API is not enough since it will cause
warning in some contexts where the lock is obtained with hard irqs
disabled. To fix the issue save current irq state, disable them before
obtaining the lock an re-enable irqs from saved state after releasing it.

[0]:

[Sun Aug  7 13:12:29 2022] ================================
[Sun Aug  7 13:12:29 2022] WARNING: inconsistent lock state
[Sun Aug  7 13:12:29 2022] 5.19.0_for_upstream_debug_2022_08_04_16_06 #1 Not tainted
[Sun Aug  7 13:12:29 2022] --------------------------------
[Sun Aug  7 13:12:29 2022] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[Sun Aug  7 13:12:29 2022] swapper/0/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
[Sun Aug  7 13:12:29 2022] ffffffffa06dc0d8 (lag_lock){+.?.}-{2:2}, at: mlx5_lag_is_shared_fdb+0x1f/0x120 [mlx5_core]
[Sun Aug  7 13:12:29 2022] {SOFTIRQ-ON-W} state was registered at:
[Sun Aug  7 13:12:29 2022]   lock_acquire+0x1c1/0x550
[Sun Aug  7 13:12:29 2022]   _raw_spin_lock+0x2c/0x40
[Sun Aug  7 13:12:29 2022]   mlx5_lag_add_netdev+0x13b/0x480 [mlx5_core]
[Sun Aug  7 13:12:29 2022]   mlx5e_nic_enable+0x114/0x470 [mlx5_core]
[Sun Aug  7 13:12:29 2022]   mlx5e_attach_netdev+0x30e/0x6a0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]   mlx5e_resume+0x105/0x160 [mlx5_core]
[Sun Aug  7 13:12:29 2022]   mlx5e_probe+0xac3/0x14f0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]   auxiliary_bus_probe+0x9d/0xe0
[Sun Aug  7 13:12:29 2022]   really_probe+0x1e0/0xaa0
[Sun Aug  7 13:12:29 2022]   __driver_probe_device+0x219/0x480
[Sun Aug  7 13:12:29 2022]   driver_probe_device+0x49/0x130
[Sun Aug  7 13:12:29 2022]   __driver_attach+0x1e4/0x4d0
[Sun Aug  7 13:12:29 2022]   bus_for_each_dev+0x11e/0x1a0
[Sun Aug  7 13:12:29 2022]   bus_add_driver+0x3f4/0x5a0
[Sun Aug  7 13:12:29 2022]   driver_register+0x20f/0x390
[Sun Aug  7 13:12:29 2022]   __auxiliary_driver_register+0x14e/0x260
[Sun Aug  7 13:12:29 2022]   mlx5e_init+0x38/0x90 [mlx5_core]
[Sun Aug  7 13:12:29 2022]   vhost_iotlb_itree_augment_rotate+0xcb/0x180 [vhost_iotlb]
[Sun Aug  7 13:12:29 2022]   do_one_initcall+0xc4/0x400
[Sun Aug  7 13:12:29 2022]   do_init_module+0x18a/0x620
[Sun Aug  7 13:12:29 2022]   load_module+0x563a/0x7040
[Sun Aug  7 13:12:29 2022]   __do_sys_finit_module+0x122/0x1d0
[Sun Aug  7 13:12:29 2022]   do_syscall_64+0x3d/0x90
[Sun Aug  7 13:12:29 2022]   entry_SYSCALL_64_after_hwframe+0x46/0xb0
[Sun Aug  7 13:12:29 2022] irq event stamp: 3596508
[Sun Aug  7 13:12:29 2022] hardirqs last  enabled at (3596508): [<ffffffff813687c2>] __local_bh_enable_ip+0xa2/0x100
[Sun Aug  7 13:12:29 2022] hardirqs last disabled at (3596507): [<ffffffff813687da>] __local_bh_enable_ip+0xba/0x100
[Sun Aug  7 13:12:29 2022] softirqs last  enabled at (3596488): [<ffffffff81368a2a>] irq_exit_rcu+0x11a/0x170
[Sun Aug  7 13:12:29 2022] softirqs last disabled at (3596495): [<ffffffff81368a2a>] irq_exit_rcu+0x11a/0x170
[Sun Aug  7 13:12:29 2022]
                           other info that might help us debug this:
[Sun Aug  7 13:12:29 2022]  Possible unsafe locking scenario:

[Sun Aug  7 13:12:29 2022]        CPU0
[Sun Aug  7 13:12:29 2022]        ----
[Sun Aug  7 13:12:29 2022]   lock(lag_lock);
[Sun Aug  7 13:12:29 2022]   <Interrupt>
[Sun Aug  7 13:12:29 2022]     lock(lag_lock);
[Sun Aug  7 13:12:29 2022]
                            *** DEADLOCK ***

[Sun Aug  7 13:12:29 2022] 4 locks held by swapper/0/0:
[Sun Aug  7 13:12:29 2022]  #0: ffffffff84643260 (rcu_read_lock){....}-{1:2}, at: mlx5e_napi_poll+0x43/0x20a0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  #1: ffffffff84643260 (rcu_read_lock){....}-{1:2}, at: netif_receive_skb_list_internal+0x2d7/0xd60
[Sun Aug  7 13:12:29 2022]  #2: ffff888144a18b58 (&br->hash_lock){+.-.}-{2:2}, at: br_fdb_update+0x301/0x570
[Sun Aug  7 13:12:29 2022]  #3: ffffffff84643260 (rcu_read_lock){....}-{1:2}, at: atomic_notifier_call_chain+0x5/0x1d0
[Sun Aug  7 13:12:29 2022]
                           stack backtrace:
[Sun Aug  7 13:12:29 2022] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0_for_upstream_debug_2022_08_04_16_06 #1
[Sun Aug  7 13:12:29 2022] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[Sun Aug  7 13:12:29 2022] Call Trace:
[Sun Aug  7 13:12:29 2022]  <IRQ>
[Sun Aug  7 13:12:29 2022]  dump_stack_lvl+0x57/0x7d
[Sun Aug  7 13:12:29 2022]  mark_lock.part.0.cold+0x5f/0x92
[Sun Aug  7 13:12:29 2022]  ? lock_chain_count+0x20/0x20
[Sun Aug  7 13:12:29 2022]  ? unwind_next_frame+0x1c4/0x1b50
[Sun Aug  7 13:12:29 2022]  ? secondary_startup_64_no_verify+0xcd/0xdb
[Sun Aug  7 13:12:29 2022]  ? mlx5e_napi_poll+0x4e9/0x20a0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? mlx5e_napi_poll+0x4e9/0x20a0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? stack_access_ok+0x1d0/0x1d0
[Sun Aug  7 13:12:29 2022]  ? start_kernel+0x3a7/0x3c5
[Sun Aug  7 13:12:29 2022]  __lock_acquire+0x1260/0x6720
[Sun Aug  7 13:12:29 2022]  ? lock_chain_count+0x20/0x20
[Sun Aug  7 13:12:29 2022]  ? lock_chain_count+0x20/0x20
[Sun Aug  7 13:12:29 2022]  ? register_lock_class+0x1880/0x1880
[Sun Aug  7 13:12:29 2022]  ? mark_lock.part.0+0xed/0x3060
[Sun Aug  7 13:12:29 2022]  ? stack_trace_save+0x91/0xc0
[Sun Aug  7 13:12:29 2022]  lock_acquire+0x1c1/0x550
[Sun Aug  7 13:12:29 2022]  ? mlx5_lag_is_shared_fdb+0x1f/0x120 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? lockdep_hardirqs_on_prepare+0x400/0x400
[Sun Aug  7 13:12:29 2022]  ? __lock_acquire+0xd6f/0x6720
[Sun Aug  7 13:12:29 2022]  _raw_spin_lock+0x2c/0x40
[Sun Aug  7 13:12:29 2022]  ? mlx5_lag_is_shared_fdb+0x1f/0x120 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  mlx5_lag_is_shared_fdb+0x1f/0x120 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  mlx5_esw_bridge_rep_vport_num_vhca_id_get+0x1a0/0x600 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? mlx5_esw_bridge_update_work+0x90/0x90 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? lock_acquire+0x1c1/0x550
[Sun Aug  7 13:12:29 2022]  mlx5_esw_bridge_switchdev_event+0x185/0x8f0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? mlx5_esw_bridge_port_obj_attr_set+0x3e0/0x3e0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? check_chain_key+0x24a/0x580
[Sun Aug  7 13:12:29 2022]  atomic_notifier_call_chain+0xd7/0x1d0
[Sun Aug  7 13:12:29 2022]  br_switchdev_fdb_notify+0xea/0x100
[Sun Aug  7 13:12:29 2022]  ? br_switchdev_set_port_flag+0x310/0x310
[Sun Aug  7 13:12:29 2022]  fdb_notify+0x11b/0x150
[Sun Aug  7 13:12:29 2022]  br_fdb_update+0x34c/0x570
[Sun Aug  7 13:12:29 2022]  ? lock_chain_count+0x20/0x20
[Sun Aug  7 13:12:29 2022]  ? br_fdb_add_local+0x50/0x50
[Sun Aug  7 13:12:29 2022]  ? br_allowed_ingress+0x5f/0x1070
[Sun Aug  7 13:12:29 2022]  ? check_chain_key+0x24a/0x580
[Sun Aug  7 13:12:29 2022]  br_handle_frame_finish+0x786/0x18e0
[Sun Aug  7 13:12:29 2022]  ? check_chain_key+0x24a/0x580
[Sun Aug  7 13:12:29 2022]  ? br_handle_local_finish+0x20/0x20
[Sun Aug  7 13:12:29 2022]  ? __lock_acquire+0xd6f/0x6720
[Sun Aug  7 13:12:29 2022]  ? sctp_inet_bind_verify+0x4d/0x190
[Sun Aug  7 13:12:29 2022]  ? xlog_unpack_data+0x2e0/0x310
[Sun Aug  7 13:12:29 2022]  ? br_handle_local_finish+0x20/0x20
[Sun Aug  7 13:12:29 2022]  br_nf_hook_thresh+0x227/0x380 [br_netfilter]
[Sun Aug  7 13:12:29 2022]  ? setup_pre_routing+0x460/0x460 [br_netfilter]
[Sun Aug  7 13:12:29 2022]  ? br_handle_local_finish+0x20/0x20
[Sun Aug  7 13:12:29 2022]  ? br_nf_pre_routing_ipv6+0x48b/0x69c [br_netfilter]
[Sun Aug  7 13:12:29 2022]  br_nf_pre_routing_finish_ipv6+0x5c2/0xbf0 [br_netfilter]
[Sun Aug  7 13:12:29 2022]  ? br_handle_local_finish+0x20/0x20
[Sun Aug  7 13:12:29 2022]  br_nf_pre_routing_ipv6+0x4c6/0x69c [br_netfilter]
[Sun Aug  7 13:12:29 2022]  ? br_validate_ipv6+0x9e0/0x9e0 [br_netfilter]
[Sun Aug  7 13:12:29 2022]  ? br_nf_forward_arp+0xb70/0xb70 [br_netfilter]
[Sun Aug  7 13:12:29 2022]  ? br_nf_pre_routing+0xacf/0x1160 [br_netfilter]
[Sun Aug  7 13:12:29 2022]  br_handle_frame+0x8a9/0x1270
[Sun Aug  7 13:12:29 2022]  ? br_handle_frame_finish+0x18e0/0x18e0
[Sun Aug  7 13:12:29 2022]  ? register_lock_class+0x1880/0x1880
[Sun Aug  7 13:12:29 2022]  ? br_handle_local_finish+0x20/0x20
[Sun Aug  7 13:12:29 2022]  ? bond_handle_frame+0xf9/0xac0 [bonding]
[Sun Aug  7 13:12:29 2022]  ? br_handle_frame_finish+0x18e0/0x18e0
[Sun Aug  7 13:12:29 2022]  __netif_receive_skb_core+0x7c0/0x2c70
[Sun Aug  7 13:12:29 2022]  ? check_chain_key+0x24a/0x580
[Sun Aug  7 13:12:29 2022]  ? generic_xdp_tx+0x5b0/0x5b0
[Sun Aug  7 13:12:29 2022]  ? __lock_acquire+0xd6f/0x6720
[Sun Aug  7 13:12:29 2022]  ? register_lock_class+0x1880/0x1880
[Sun Aug  7 13:12:29 2022]  ? check_chain_key+0x24a/0x580
[Sun Aug  7 13:12:29 2022]  __netif_receive_skb_list_core+0x2d7/0x8a0
[Sun Aug  7 13:12:29 2022]  ? lock_acquire+0x1c1/0x550
[Sun Aug  7 13:12:29 2022]  ? process_backlog+0x960/0x960
[Sun Aug  7 13:12:29 2022]  ? lockdep_hardirqs_on_prepare+0x129/0x400
[Sun Aug  7 13:12:29 2022]  ? kvm_clock_get_cycles+0x14/0x20
[Sun Aug  7 13:12:29 2022]  netif_receive_skb_list_internal+0x5f4/0xd60
[Sun Aug  7 13:12:29 2022]  ? do_xdp_generic+0x150/0x150
[Sun Aug  7 13:12:29 2022]  ? mlx5e_poll_rx_cq+0xf6b/0x2960 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? mlx5e_poll_ico_cq+0x3d/0x1590 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  napi_complete_done+0x188/0x710
[Sun Aug  7 13:12:29 2022]  mlx5e_napi_poll+0x4e9/0x20a0 [mlx5_core]
[Sun Aug  7 13:12:29 2022]  ? __queue_work+0x53c/0xeb0
[Sun Aug  7 13:12:29 2022]  __napi_poll+0x9f/0x540
[Sun Aug  7 13:12:29 2022]  net_rx_action+0x420/0xb70
[Sun Aug  7 13:12:29 2022]  ? napi_threaded_poll+0x470/0x470
[Sun Aug  7 13:12:29 2022]  ? __common_interrupt+0x79/0x1a0
[Sun Aug  7 13:12:29 2022]  __do_softirq+0x271/0x92c
[Sun Aug  7 13:12:29 2022]  irq_exit_rcu+0x11a/0x170
[Sun Aug  7 13:12:29 2022]  common_interrupt+0x7d/0xa0
[Sun Aug  7 13:12:29 2022]  </IRQ>
[Sun Aug  7 13:12:29 2022]  <TASK>
[Sun Aug  7 13:12:29 2022]  asm_common_interrupt+0x22/0x40
[Sun Aug  7 13:12:29 2022] RIP: 0010:default_idle+0x42/0x60
[Sun Aug  7 13:12:29 2022] Code: c1 83 e0 07 48 c1 e9 03 83 c0 03 0f b6 14 11 38 d0 7c 04 84 d2 75 14 8b 05 6b f1 22 02 85 c0 7e 07 0f 00 2d 80 3b 4a 00 fb f4 <c3> 48 c7 c7 e0 07 7e 85 e8 21 bd 40 fe eb de 66 66 2e 0f 1f 84 00
[Sun Aug  7 13:12:29 2022] RSP: 0018:ffffffff84407e18 EFLAGS: 00000242
[Sun Aug  7 13:12:29 2022] RAX: 0000000000000001 RBX: ffffffff84ec4a68 RCX: 1ffffffff0afc0fc
[Sun Aug  7 13:12:29 2022] RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffff835b1fac
[Sun Aug  7 13:12:29 2022] RBP: 0000000000000000 R08: 0000000000000001 R09: ffff8884d2c44ac3
[Sun Aug  7 13:12:29 2022] R10: ffffed109a588958 R11: 00000000ffffffff R12: 0000000000000000
[Sun Aug  7 13:12:29 2022] R13: ffffffff84efac20 R14: 0000000000000000 R15: dffffc0000000000
[Sun Aug  7 13:12:29 2022]  ? default_idle_call+0xcc/0x460
[Sun Aug  7 13:12:29 2022]  default_idle_call+0xec/0x460
[Sun Aug  7 13:12:29 2022]  do_idle+0x394/0x450
[Sun Aug  7 13:12:29 2022]  ? arch_cpu_idle_exit+0x40/0x40
[Sun Aug  7 13:12:29 2022]  cpu_startup_entry+0x19/0x20
[Sun Aug  7 13:12:29 2022]  rest_init+0x156/0x250
[Sun Aug  7 13:12:29 2022]  arch_call_rest_init+0xf/0x15
[Sun Aug  7 13:12:29 2022]  start_kernel+0x3a7/0x3c5
[Sun Aug  7 13:12:29 2022]  secondary_startup_64_no_verify+0xcd/0xdb
[Sun Aug  7 13:12:29 2022]  </TASK>

Fixes: ff9b752146 ("net/mlx5: Bridge, support LAG")
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
2022-08-22 12:57:07 -07:00
arch virtio: fixes 2022-08-17 08:58:54 -07:00
block block-6.0-2022-08-12 2022-08-13 13:37:36 -07:00
certs Kbuild updates for v5.20 2022-08-10 10:40:41 -07:00
crypto crypto: blake2b: effectively disable frame size warning 2022-08-10 17:59:11 -07:00
Documentation Including fixes from netfilter. 2022-08-18 19:37:15 -07:00
drivers net/mlx5: Disable irq when locking lag_lock 2022-08-22 12:57:07 -07:00
fs ntfs3 for 6.0 2022-08-17 14:51:22 -07:00
include Including fixes from netfilter. 2022-08-18 19:37:15 -07:00
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usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt KVM: Actually create debugfs in kvm_create_vm() 2022-08-10 15:08:28 -04:00
.clang-format PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
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CREDITS drm for 5.20/6.0 2022-08-03 19:52:08 -07:00
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Makefile Linux 6.0-rc1 2022-08-14 15:50:18 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.