Re: [4.15-rc9] fs_reclaim lockdep trace

[Dave Jones <davej@codemonkey.org.uk>]

On Tue, Jan 23, 2018 at 08:36:51PM -0500, Dave Jones wrote:
 > Just triggered this on a server I was rsync'ing to.

Actually, I can trigger this really easily, even with an rsync from one
disk to another.  Though that also smells a little like networking in
the traces. Maybe netdev has ideas.

 
The first instance:

 > ============================================
 > WARNING: possible recursive locking detected
 > 4.15.0-rc9-backup-debug+ #1 Not tainted
 > --------------------------------------------
 > sshd/24800 is trying to acquire lock:
 >  (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30
 > 
 > but task is already holding lock:
 >  (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30
 > 
 > other info that might help us debug this:
 >  Possible unsafe locking scenario:
 > 
 >        CPU0
 >        ----
 >   lock(fs_reclaim);
 >   lock(fs_reclaim);
 > 
 >  *** DEADLOCK ***
 > 
 >  May be due to missing lock nesting notation
 > 
 > 2 locks held by sshd/24800:
 >  #0:  (sk_lock-AF_INET6){+.+.}, at: [<000000001a069652>] tcp_sendmsg+0x19/0x40
 >  #1:  (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30
 > 
 > stack backtrace:
 > CPU: 3 PID: 24800 Comm: sshd Not tainted 4.15.0-rc9-backup-debug+ #1
 > Call Trace:
 >  dump_stack+0xbc/0x13f
 >  ? _atomic_dec_and_lock+0x101/0x101
 >  ? fs_reclaim_acquire.part.102+0x5/0x30
 >  ? print_lock+0x54/0x68
 >  __lock_acquire+0xa09/0x2040
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? mutex_destroy+0x120/0x120
 >  ? hlock_class+0xa0/0xa0
 >  ? kernel_text_address+0x5c/0x90
 >  ? __kernel_text_address+0xe/0x30
 >  ? unwind_get_return_address+0x2f/0x50
 >  ? __save_stack_trace+0x92/0x100
 >  ? graph_lock+0x8d/0x100
 >  ? check_noncircular+0x20/0x20
 >  ? __lock_acquire+0x616/0x2040
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? __lock_acquire+0x616/0x2040
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? print_irqtrace_events+0x110/0x110
 >  ? active_load_balance_cpu_stop+0x7b0/0x7b0
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? mark_lock+0x1b1/0xa00
 >  ? lock_acquire+0x12e/0x350
 >  lock_acquire+0x12e/0x350
 >  ? fs_reclaim_acquire.part.102+0x5/0x30
 >  ? lockdep_rcu_suspicious+0x100/0x100
 >  ? set_next_entity+0x20e/0x10d0
 >  ? mark_lock+0x1b1/0xa00
 >  ? match_held_lock+0x8d/0x440
 >  ? mark_lock+0x1b1/0xa00
 >  ? save_trace+0x1e0/0x1e0
 >  ? print_irqtrace_events+0x110/0x110
 >  ? alloc_extent_state+0xa7/0x410
 >  fs_reclaim_acquire.part.102+0x29/0x30
 >  ? fs_reclaim_acquire.part.102+0x5/0x30
 >  kmem_cache_alloc+0x3d/0x2c0
 >  ? rb_erase+0xe63/0x1240
 >  alloc_extent_state+0xa7/0x410
 >  ? lock_extent_buffer_for_io+0x3f0/0x3f0
 >  ? find_held_lock+0x6d/0xd0
 >  ? test_range_bit+0x197/0x210
 >  ? lock_acquire+0x350/0x350
 >  ? do_raw_spin_unlock+0x147/0x220
 >  ? do_raw_spin_trylock+0x100/0x100
 >  ? iotree_fs_info+0x30/0x30
 >  __clear_extent_bit+0x3ea/0x570
 >  ? clear_state_bit+0x270/0x270
 >  ? count_range_bits+0x2f0/0x2f0
 >  ? lock_acquire+0x350/0x350
 >  ? rb_prev+0x21/0x90
 >  try_release_extent_mapping+0x21a/0x260
 >  __btrfs_releasepage+0xb0/0x1c0
 >  ? btrfs_submit_direct+0xca0/0xca0
 >  ? check_new_page_bad+0x1f0/0x1f0
 >  ? match_held_lock+0xa5/0x440
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  btrfs_releasepage+0x161/0x170
 >  ? __btrfs_releasepage+0x1c0/0x1c0
 >  ? page_rmapping+0xd0/0xd0
 >  ? rmap_walk+0x100/0x100
 >  try_to_release_page+0x162/0x1c0
 >  ? generic_file_write_iter+0x3c0/0x3c0
 >  ? page_evictable+0xcc/0x110
 >  ? lookup_address_in_pgd+0x107/0x190
 >  shrink_page_list+0x1d5a/0x2fb0
 >  ? putback_lru_page+0x3f0/0x3f0
 >  ? save_trace+0x1e0/0x1e0
 >  ? _lookup_address_cpa.isra.13+0x40/0x60
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? kmem_cache_free+0x8c/0x280
 >  ? free_extent_state+0x1c8/0x3b0
 >  ? mark_lock+0x1b1/0xa00
 >  ? page_rmapping+0xd0/0xd0
 >  ? print_irqtrace_events+0x110/0x110
 >  ? shrink_node_memcg.constprop.88+0x4c9/0x5e0
 >  ? shrink_node+0x12d/0x260
 >  ? try_to_free_pages+0x418/0xaf0
 >  ? __alloc_pages_slowpath+0x976/0x1790
 >  ? __alloc_pages_nodemask+0x52c/0x5c0
 >  ? delete_node+0x28d/0x5c0
 >  ? find_held_lock+0x6d/0xd0
 >  ? free_pcppages_bulk+0x381/0x570
 >  ? lock_acquire+0x350/0x350
 >  ? do_raw_spin_unlock+0x147/0x220
 >  ? do_raw_spin_trylock+0x100/0x100
 >  ? __lock_is_held+0x51/0xc0
 >  ? _raw_spin_unlock+0x24/0x30
 >  ? free_pcppages_bulk+0x381/0x570
 >  ? mark_lock+0x1b1/0xa00
 >  ? free_compound_page+0x30/0x30
 >  ? print_irqtrace_events+0x110/0x110
 >  ? __kernel_map_pages+0x2c9/0x310
 >  ? mark_lock+0x1b1/0xa00
 >  ? print_irqtrace_events+0x110/0x110
 >  ? __delete_from_page_cache+0x2e7/0x4e0
 >  ? save_trace+0x1e0/0x1e0
 >  ? __add_to_page_cache_locked+0x680/0x680
 >  ? find_held_lock+0x6d/0xd0
 >  ? __list_add_valid+0x29/0xa0
 >  ? free_unref_page_commit+0x198/0x270
 >  ? drain_local_pages_wq+0x20/0x20
 >  ? stop_critical_timings+0x210/0x210
 >  ? mark_lock+0x1b1/0xa00
 >  ? mark_lock+0x1b1/0xa00
 >  ? print_irqtrace_events+0x110/0x110
 >  ? __lock_acquire+0x616/0x2040
 >  ? mark_lock+0x1b1/0xa00
 >  ? mark_lock+0x1b1/0xa00
 >  ? print_irqtrace_events+0x110/0x110
 >  ? __phys_addr_symbol+0x23/0x40
 >  ? __change_page_attr_set_clr+0xe86/0x1640
 >  ? __btrfs_releasepage+0x1c0/0x1c0
 >  ? mark_lock+0x1b1/0xa00
 >  ? mark_lock+0x1b1/0xa00
 >  ? print_irqtrace_events+0x110/0x110
 >  ? mark_lock+0x1b1/0xa00
 >  ? __lock_acquire+0x616/0x2040
 >  ? __lock_acquire+0x616/0x2040
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? swiotlb_free_coherent+0x60/0x60
 >  ? __phys_addr+0x32/0x80
 >  ? igb_xmit_frame_ring+0xad7/0x1890
 >  ? stack_access_ok+0x35/0x80
 >  ? deref_stack_reg+0xa1/0xe0
 >  ? __read_once_size_nocheck.constprop.6+0x10/0x10
 >  ? __orc_find+0x6b/0xc0
 >  ? unwind_next_frame+0x407/0xa20
 >  ? __save_stack_trace+0x5e/0x100
 >  ? stack_access_ok+0x35/0x80
 >  ? deref_stack_reg+0xa1/0xe0
 >  ? __read_once_size_nocheck.constprop.6+0x10/0x10
 >  ? __lock_acquire+0x616/0x2040
 >  ? debug_lockdep_rcu_enabled.part.37+0x16/0x30
 >  ? is_ftrace_trampoline+0x112/0x190
 >  ? ftrace_profile_pages_init+0x130/0x130
 >  ? unwind_next_frame+0x407/0xa20
 >  ? rcu_is_watching+0x88/0xd0
 >  ? unwind_get_return_address_ptr+0x50/0x50
 >  ? kernel_text_address+0x5c/0x90
 >  ? __kernel_text_address+0xe/0x30
 >  ? unwind_get_return_address+0x2f/0x50
 >  ? __save_stack_trace+0x92/0x100
 >  ? __list_add_valid+0x29/0xa0
 >  ? add_lock_to_list.isra.26+0x1d0/0x21f
 >  ? print_lockdep_cache.isra.29+0xd8/0xd8
 >  ? save_trace+0x106/0x1e0
 >  ? __isolate_lru_page+0x2dc/0x3c0
 >  ? remove_mapping+0x1b0/0x1b0
 >  ? match_held_lock+0xa5/0x440
 >  ? __lock_acquire+0x616/0x2040
 >  ? __mod_zone_page_state+0x1a/0x70
 >  ? isolate_lru_pages.isra.83+0x888/0xae0
 >  ? __isolate_lru_page+0x3c0/0x3c0
 >  ? check_usage+0x174/0x790
 >  ? mark_lock+0x1b1/0xa00
 >  ? print_irqtrace_events+0x110/0x110
 >  ? check_usage_forwards+0x2b0/0x2b0
 >  ? class_equal+0x11/0x20
 >  ? __bfs+0xed/0x430
 >  ? __phys_addr_symbol+0x23/0x40
 >  ? mutex_destroy+0x120/0x120
 >  ? match_held_lock+0x8d/0x440
 >  ? hlock_class+0xa0/0xa0
 >  ? mark_lock+0x1b1/0xa00
 >  ? save_trace+0x1e0/0x1e0
 >  ? print_irqtrace_events+0x110/0x110
 >  ? lock_acquire+0x350/0x350
 >  ? __zone_watermark_ok+0xd8/0x280
 >  ? graph_lock+0x8d/0x100
 >  ? check_noncircular+0x20/0x20
 >  ? find_held_lock+0x6d/0xd0
 >  ? shrink_inactive_list+0x3b4/0x940
 >  ? lock_acquire+0x350/0x350
 >  ? do_raw_spin_unlock+0x147/0x220
 >  ? do_raw_spin_trylock+0x100/0x100
 >  ? stop_critical_timings+0x210/0x210
 >  ? mark_held_locks+0x6e/0x90
 >  ? _raw_spin_unlock_irq+0x29/0x40
 >  shrink_inactive_list+0x451/0x940
 >  ? save_trace+0x180/0x1e0
 >  ? putback_inactive_pages+0x9f0/0x9f0
 >  ? dev_queue_xmit_nit+0x548/0x660
 >  ? __kernel_map_pages+0x2c9/0x310
 >  ? set_pages_rw+0xe0/0xe0
 >  ? get_page_from_freelist+0x1ea5/0x2ca0
 >  ? match_held_lock+0x8d/0x440
 >  ? blk_start_plug+0x17d/0x1e0
 >  ? kblockd_schedule_delayed_work_on+0x20/0x20
 >  ? print_irqtrace_events+0x110/0x110
 >  ? cpumask_next+0x1d/0x20
 >  ? zone_reclaimable_pages+0x25b/0x470
 >  ? mark_held_locks+0x6e/0x90
 >  ? __remove_mapping+0x4e0/0x4e0
 >  shrink_node_memcg.constprop.88+0x4c9/0x5e0
 >  ? __delayacct_freepages_start+0x28/0x40
 >  ? lock_acquire+0x311/0x350
 >  ? shrink_active_list+0x9c0/0x9c0
 >  ? stop_critical_timings+0x210/0x210
 >  ? allow_direct_reclaim.part.82+0xea/0x220
 >  ? mark_held_locks+0x6e/0x90
 >  ? ktime_get+0x1f0/0x3e0
 >  ? shrink_node+0x12d/0x260
 >  shrink_node+0x12d/0x260
 >  ? shrink_node_memcg.constprop.88+0x5e0/0x5e0
 >  ? __lock_is_held+0x51/0xc0
 >  try_to_free_pages+0x418/0xaf0
 >  ? shrink_node+0x260/0x260
 >  ? lock_acquire+0x12e/0x350
 >  ? lock_acquire+0x12e/0x350
 >  ? fs_reclaim_acquire.part.102+0x5/0x30
 >  ? lockdep_rcu_suspicious+0x100/0x100
 >  ? rcu_note_context_switch+0x520/0x520
 >  ? wake_all_kswapds+0x10a/0x150
 >  __alloc_pages_slowpath+0x976/0x1790
 >  ? __zone_watermark_ok+0x280/0x280
 >  ? warn_alloc+0x250/0x250
 >  ? __lock_acquire+0x616/0x2040
 >  ? match_held_lock+0x8d/0x440
 >  ? save_trace+0x1e0/0x1e0
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? match_held_lock+0xa5/0x440
 >  ? stack_access_ok+0x35/0x80
 >  ? save_trace+0x1e0/0x1e0
 >  ? __read_once_size_nocheck.constprop.6+0x10/0x10
 >  ? __lock_acquire+0x616/0x2040
 >  ? match_held_lock+0xa5/0x440
 >  ? find_held_lock+0x6d/0xd0
 >  ? __lock_is_held+0x51/0xc0
 >  ? rcu_note_context_switch+0x520/0x520
 >  ? perf_trace_sched_switch+0x560/0x560
 >  ? __might_sleep+0x58/0xe0
 >  __alloc_pages_nodemask+0x52c/0x5c0
 >  ? gfp_pfmemalloc_allowed+0xc0/0xc0
 >  ? kernel_text_address+0x5c/0x90
 >  ? __kernel_text_address+0xe/0x30
 >  ? unwind_get_return_address+0x2f/0x50
 >  ? memcmp+0x45/0x70
 >  ? match_held_lock+0x8d/0x440
 >  ? depot_save_stack+0x12e/0x480
 >  ? match_held_lock+0xa5/0x440
 >  ? stop_critical_timings+0x210/0x210
 >  ? sk_stream_alloc_skb+0xb8/0x340
 >  ? mark_held_locks+0x6e/0x90
 >  ? new_slab+0x2f3/0x3f0
 >  new_slab+0x374/0x3f0
 >  ___slab_alloc.constprop.81+0x47e/0x5a0
 >  ? __alloc_skb+0xee/0x390
 >  ? __alloc_skb+0xee/0x390
 >  ? __alloc_skb+0xee/0x390
 >  ? __slab_alloc.constprop.80+0x32/0x60
 >  __slab_alloc.constprop.80+0x32/0x60
 >  ? __alloc_skb+0xee/0x390
 >  __kmalloc_track_caller+0x267/0x310
 >  __kmalloc_reserve.isra.40+0x29/0x80
 >  __alloc_skb+0xee/0x390
 >  ? __skb_splice_bits+0x3e0/0x3e0
 >  ? ip6_mtu+0x1d9/0x290
 >  ? ip6_link_failure+0x3c0/0x3c0
 >  ? tcp_current_mss+0x1d8/0x2f0
 >  ? tcp_sync_mss+0x520/0x520
 >  sk_stream_alloc_skb+0xb8/0x340
 >  ? tcp_ioctl+0x280/0x280
 >  tcp_sendmsg_locked+0x8e6/0x1d30
 >  ? match_held_lock+0x8d/0x440
 >  ? mark_lock+0x1b1/0xa00
 >  ? tcp_set_state+0x450/0x450
 >  ? debug_show_all_locks+0x2f0/0x2f0
 >  ? match_held_lock+0x8d/0x440
 >  ? save_trace+0x1e0/0x1e0
 >  ? find_held_lock+0x6d/0xd0
 >  ? lock_acquire+0x12e/0x350
 >  ? lock_acquire+0x12e/0x350
 >  ? tcp_sendmsg+0x19/0x40
 >  ? lockdep_rcu_suspicious+0x100/0x100
 >  ? do_raw_spin_trylock+0x100/0x100
 >  ? stop_critical_timings+0x210/0x210
 >  ? mark_held_locks+0x6e/0x90
 >  ? __local_bh_enable_ip+0x94/0x100
 >  ? lock_sock_nested+0x51/0xb0
 >  tcp_sendmsg+0x27/0x40
 >  inet_sendmsg+0xd0/0x310
 >  ? inet_recvmsg+0x360/0x360
 >  ? match_held_lock+0x8d/0x440
 >  ? inet_recvmsg+0x360/0x360
 >  sock_write_iter+0x17a/0x240
 >  ? sock_ioctl+0x290/0x290
 >  ? find_held_lock+0x6d/0xd0
 >  __vfs_write+0x2ab/0x380
 >  ? kernel_read+0xa0/0xa0
 >  ? __context_tracking_exit.part.4+0xe7/0x290
 >  ? lock_acquire+0x350/0x350
 >  ? __fdget_pos+0x7f/0x110
 >  ? __fdget_raw+0x10/0x10
 >  vfs_write+0xfb/0x260
 >  SyS_write+0xb6/0x140
 >  ? SyS_read+0x140/0x140
 >  ? SyS_clock_settime+0x120/0x120
 >  ? mark_held_locks+0x1c/0x90
 >  ? do_syscall_64+0x110/0xc05
 >  ? SyS_read+0x140/0x140
 >  do_syscall_64+0x1e5/0xc05
 >  ? syscall_return_slowpath+0x5b0/0x5b0
 >  ? lock_acquire+0x350/0x350
 >  ? lockdep_rcu_suspicious+0x100/0x100
 >  ? get_vtime_delta+0x15/0xf0
 >  ? get_vtime_delta+0x8b/0xf0
 >  ? vtime_user_enter+0x7f/0x90
 >  ? __context_tracking_enter+0x13c/0x2b0
 >  ? __context_tracking_enter+0x13c/0x2b0
 >  ? context_tracking_exit.part.5+0x40/0x40
 >  ? rcu_is_watching+0x88/0xd0
 >  ? time_hardirqs_on+0x220/0x220
 >  ? prepare_exit_to_usermode+0x1d0/0x2a0
 >  ? enter_from_user_mode+0x30/0x30
 >  ? entry_SYSCALL_64_after_hwframe+0x18/0x2e
 >  ? trace_hardirqs_off_caller+0xc2/0x110
 >  ? trace_hardirqs_off_thunk+0x1a/0x1c
 >  entry_SYSCALL64_slow_path+0x25/0x25
 

 And now I can hit..



============================================
WARNING: possible recursive locking detected
4.15.0-rc9-backup-debug+ #7 Not tainted
--------------------------------------------
snmpd/892 is trying to acquire lock:
 (fs_reclaim){+.+.}, at: [<0000000002e4c185>] fs_reclaim_acquire.part.101+0x5/0x30

but task is already holding lock:
 (fs_reclaim){+.+.}, at: [<0000000002e4c185>] fs_reclaim_acquire.part.101+0x5/0x30

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(fs_reclaim);
  lock(fs_reclaim);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by snmpd/892:
 #0:  (rtnl_mutex){+.+.}, at: [<00000000dcd3ba2f>] netlink_dump+0x89/0x520
 #1:  (fs_reclaim){+.+.}, at: [<0000000002e4c185>] fs_reclaim_acquire.part.101+0x5/0x30

stack backtrace:
CPU: 5 PID: 892 Comm: snmpd Not tainted 4.15.0-rc9-backup-debug+ #7
Call Trace:
 dump_stack+0xbc/0x13f
 ? _atomic_dec_and_lock+0x101/0x101
 ? fs_reclaim_acquire.part.101+0x5/0x30
 ? print_lock+0x54/0x68
 __lock_acquire+0xa09/0x2040
 ? debug_show_all_locks+0x2f0/0x2f0
 ? __save_stack_trace+0x92/0x100
 ? __list_add_valid+0x29/0xa0
 ? add_lock_to_list.isra.26+0x1d0/0x21f
 ? print_lockdep_cache.isra.29+0xd8/0xd8
 ? save_trace+0x106/0x1e0
 ? graph_lock+0x100/0x100
 ? graph_lock+0x8d/0x100
 ? check_noncircular+0x20/0x20
 ? __lock_acquire+0x616/0x2040
 ? debug_show_all_locks+0x2f0/0x2f0
 ? lock_acquire+0x12e/0x350
 lock_acquire+0x12e/0x350
 ? fs_reclaim_acquire.part.101+0x5/0x30
 ? lockdep_rcu_suspicious+0x100/0x100
 ? match_held_lock+0x8d/0x440
 ? save_trace+0x1e0/0x1e0
 ? alloc_extent_state+0xa7/0x410
 fs_reclaim_acquire.part.101+0x29/0x30
 ? fs_reclaim_acquire.part.101+0x5/0x30
 kmem_cache_alloc+0x3d/0x2c0
 alloc_extent_state+0xa7/0x410
 ? lock_extent_buffer_for_io+0x3f0/0x3f0
 ? find_held_lock+0x6d/0xd0
 ? test_range_bit+0x197/0x210
 ? lock_acquire+0x350/0x350
 ? do_raw_spin_unlock+0x147/0x220
 ? do_raw_spin_trylock+0x100/0x100
 ? iotree_fs_info+0x30/0x30
 __clear_extent_bit+0x3ea/0x570
 ? clear_state_bit+0x270/0x270
 ? count_range_bits+0x2f0/0x2f0
 try_release_extent_mapping+0x21a/0x260
 __btrfs_releasepage+0xb0/0x1c0
 ? btrfs_submit_direct+0xca0/0xca0
 ? check_usage+0x257/0x790
 ? match_held_lock+0xa5/0x440
 ? print_irqtrace_events+0x110/0x110
 btrfs_releasepage+0x161/0x170
 ? __btrfs_releasepage+0x1c0/0x1c0
 ? page_rmapping+0xd0/0xd0
 ? rmap_walk+0x100/0x100
 try_to_release_page+0x162/0x1c0
 ? generic_file_write_iter+0x3c0/0x3c0
 ? page_evictable+0xcc/0x110
 ? debug_show_all_locks+0x2f0/0x2f0
 shrink_page_list+0x1d5a/0x2fb0
 ? putback_lru_page+0x3f0/0x3f0
 ? match_held_lock+0x8d/0x440
 ? save_trace+0x1e0/0x1e0
 ? update_curr+0xd0/0x670
 ? __lock_is_held+0x71/0xc0
 ? update_cfs_group+0x86/0x290
 ? __list_add_valid+0x29/0xa0
 ? account_entity_dequeue+0x230/0x230
 ? nohz_balance_exit_idle.part.92+0x60/0x60
 ? __update_load_avg_se.isra.28+0x352/0x360
 ? __update_load_avg_se.isra.28+0x1f4/0x360
 ? __accumulate_pelt_segments+0x47/0xd0
 ? __enqueue_entity+0x93/0xc0
 ? match_held_lock+0x8d/0x440
 ? mark_lock+0x1b1/0xa00
 ? save_trace+0x1e0/0x1e0
 ? print_irqtrace_events+0x110/0x110
 ? check_preempt_wakeup+0x410/0x410
 ? mark_lock+0x1b1/0xa00
 ? __kernel_map_pages+0x2c9/0x310
 ? set_pages_rw+0xe0/0xe0
 ? lock_acquire+0x350/0x350
 ? lockdep_rcu_suspicious+0x100/0x100
 ? mark_held_locks+0x6e/0x90
 ? trace_hardirqs_on_caller+0x187/0x260
 ? mark_lock+0x1b1/0xa00
 ? print_irqtrace_events+0x110/0x110
 ? mark_held_locks+0x6e/0x90
 ? mark_lock+0x1b1/0xa00
 ? kasan_unpoison_shadow+0x30/0x40
 ? print_irqtrace_events+0x110/0x110
 ? mutex_destroy+0x120/0x120
 ? hlock_class+0xa0/0xa0
 ? __kernel_map_pages+0x2c9/0x310
 ? __lock_acquire+0x616/0x2040
 ? __lock_acquire+0x616/0x2040
 ? debug_show_all_locks+0x2f0/0x2f0
 ? mark_lock+0x1b1/0xa00
 ? print_irqtrace_events+0x110/0x110
 ? debug_show_all_locks+0x2f0/0x2f0
 ? debug_show_all_locks+0x2f0/0x2f0
 ? mark_held_locks+0x6e/0x90
 ? mark_lock+0x1b1/0xa00
 ? print_irqtrace_events+0x110/0x110
 ? check_usage+0x174/0x790
 ? mark_lock+0x1b1/0xa00
 ? print_irqtrace_events+0x110/0x110
 ? mark_lock+0x1b1/0xa00
 ? usage_match+0x1e/0x30
 ? print_irqtrace_events+0x110/0x110
 ? __bfs+0x2a2/0x430
 ? noop_count+0x20/0x20
 ? __lock_acquire+0x616/0x2040
 ? stack_access_ok+0x35/0x80
 ? deref_stack_reg+0xa1/0xe0
 ? __read_once_size_nocheck.constprop.6+0x10/0x10
 ? __orc_find+0x6b/0xc0
 ? unwind_next_frame+0x39c/0x9d0
 ? __save_stack_trace+0x5e/0x100
 ? save_trace+0xbd/0x1e0
 ? stack_access_ok+0x35/0x80
 ? deref_stack_reg+0xa1/0xe0
 ? __read_once_size_nocheck.constprop.6+0x10/0x10
 ? debug_lockdep_rcu_enabled.part.37+0x16/0x30
 ? ftrace_ops_trampoline+0x111/0x190
 ? ftrace_profile_pages_init+0x130/0x130
 ? unwind_next_frame+0x39c/0x9d0
 ? rcu_is_watching+0x88/0xd0
 ? rcu_nmi_exit+0x130/0x130
 ? is_ftrace_trampoline+0x5/0x10
 ? kernel_text_address+0x5c/0x90
 ? __kernel_text_address+0xe/0x30
 ? unwind_get_return_address+0x2f/0x50
 ? __save_stack_trace+0x92/0x100
 ? __list_add_valid+0x29/0xa0
 ? add_lock_to_list.isra.26+0x1d0/0x21f
 ? print_lockdep_cache.isra.29+0xd8/0xd8
 ? save_trace+0x106/0x1e0
 ? __isolate_lru_page+0x2dc/0x3c0
 ? remove_mapping+0x1b0/0x1b0
 ? match_held_lock+0xa5/0x440
 ? __lock_acquire+0x616/0x2040
 ? __mod_zone_page_state+0x1a/0x70
 ? isolate_lru_pages.isra.79+0x888/0xae0
 ? __isolate_lru_page+0x3c0/0x3c0
 ? noop_count+0x20/0x20
 ? hlock_class+0xa0/0xa0
 ? print_irqtrace_events+0x110/0x110
 ? check_usage+0x174/0x790
 ? mark_lock+0x1b1/0xa00
 ? rb_next+0x90/0x90
 ? match_held_lock+0x8d/0x440
 ? mark_lock+0x1b1/0xa00
 ? save_trace+0x1e0/0x1e0
 ? print_irqtrace_events+0x110/0x110
 ? class_equal+0x11/0x20
 ? __bfs+0xed/0x430
 ? __kernel_map_pages+0x2c9/0x310
 ? mutex_destroy+0x120/0x120
 ? find_held_lock+0x6d/0xd0
 ? shrink_inactive_list+0x3b4/0x940
 ? lock_acquire+0x350/0x350
 ? do_raw_spin_unlock+0x147/0x220
 ? do_raw_spin_trylock+0x100/0x100
 ? stop_critical_timings+0x210/0x210
 ? mark_held_locks+0x6e/0x90
 ? _raw_spin_unlock_irq+0x29/0x40
 shrink_inactive_list+0x451/0x940
 ? putback_inactive_pages+0x9f0/0x9f0
 ? isolate_migratepages_range+0x120/0x120
 ? mark_lock+0x1b1/0xa00
 ? update_curr+0x2d9/0x670
 ? compact_zone+0x1d3/0x14c0
 ? blk_start_plug+0x17d/0x1e0
 ? kblockd_schedule_delayed_work_on+0x20/0x20
 ? save_trace+0x1e0/0x1e0
 ? update_curr+0x15c/0x670
 ? active_load_balance_cpu_stop+0x7b0/0x7b0
 ? compaction_suitable+0x350/0x350
 ? update_cfs_group+0x23a/0x290
 ? match_held_lock+0x8d/0x440
 shrink_node_memcg.constprop.84+0x4c9/0x5e0
 ? shrink_active_list+0x9c0/0x9c0
 ? __delayacct_freepages_start+0x28/0x40
 ? lockdep_rcu_suspicious+0x100/0x100
 ? shrink_node+0x1c2/0x510
 shrink_node+0x1c2/0x510
 ? trace_hardirqs_on_caller+0x187/0x260
 ? shrink_node_memcg.constprop.84+0x5e0/0x5e0
 ? getnstimeofday64+0x20/0x20
 ? allow_direct_reclaim.part.78+0x220/0x220
 ? mark_lock+0x1b1/0xa00
 ? mark_lock+0x1b1/0xa00
 ? __lock_is_held+0x51/0xc0
 try_to_free_pages+0x425/0xb90
 ? shrink_node+0x510/0x510
 ? try_to_compact_pages+0x1f4/0x6b0
 ? compaction_zonelist_suitable+0x2f0/0x2f0
 ? lock_acquire+0x12e/0x350
 ? lock_acquire+0x12e/0x350
 ? fs_reclaim_acquire.part.101+0x5/0x30
 ? lockdep_rcu_suspicious+0x100/0x100
 ? rcu_note_context_switch+0x520/0x520
 ? wake_all_kswapds+0x10a/0x150
 __alloc_pages_slowpath+0x955/0x1a00
 ? __lock_acquire+0x616/0x2040
 ? warn_alloc+0x250/0x250
 ? __lock_acquire+0x616/0x2040
 ? match_held_lock+0x8d/0x440
 ? save_trace+0x1e0/0x1e0
 ? debug_show_all_locks+0x2f0/0x2f0
 ? match_held_lock+0xa5/0x440
 ? save_trace+0x1e0/0x1e0
 ? __read_once_size_nocheck.constprop.6+0x10/0x10
 ? __orc_find+0x6b/0xc0
 ? match_held_lock+0xa5/0x440
 ? find_held_lock+0x6d/0xd0
 ? __lock_is_held+0x51/0xc0
 ? rcu_note_context_switch+0x520/0x520
 ? perf_trace_sched_switch+0x560/0x560
 ? __might_sleep+0x58/0xe0
 __alloc_pages_nodemask+0x52c/0x5c0
 ? gfp_pfmemalloc_allowed+0xc0/0xc0
 ? __kernel_text_address+0xe/0x30
 ? unwind_get_return_address+0x2f/0x50
 ? __save_stack_trace+0x92/0x100
 ? match_held_lock+0x8d/0x440
 ? depot_save_stack+0x12e/0x480
 ? match_held_lock+0xa5/0x440
 ? stop_critical_timings+0x210/0x210
 ? __netlink_dump_start+0x201/0x280
 ? mark_held_locks+0x6e/0x90
 ? new_slab+0x2f3/0x3f0
 new_slab+0x374/0x3f0
 ___slab_alloc.constprop.81+0x47e/0x5a0
 ? __lock_is_held+0x51/0xc0
 ? __alloc_skb+0xee/0x390
 ? __alloc_skb+0xee/0x390
 ? __alloc_skb+0xee/0x390
 ? __slab_alloc.constprop.80+0x32/0x60
 __slab_alloc.constprop.80+0x32/0x60
 ? __alloc_skb+0xee/0x390
 __kmalloc_track_caller+0x267/0x310
 __kmalloc_reserve.isra.40+0x29/0x80
 __alloc_skb+0xee/0x390
 ? __skb_splice_bits+0x3e0/0x3e0
 ? netlink_connect+0x1d0/0x1d0
 ? __netlink_dump_start+0x1f9/0x280
 ? __mutex_unlock_slowpath+0x121/0x460
 ? wait_for_completion_killable_timeout+0x450/0x450
 ? find_held_lock+0x6d/0xd0
 netlink_dump+0x2e1/0x520
 ? refcount_inc_not_zero+0x74/0x110
 ? __nlmsg_put+0xb0/0xb0
 ? rcu_is_watching+0x88/0xd0
 __netlink_dump_start+0x201/0x280
 ? inet6_dump_ifmcaddr+0x10/0x10
 rtnetlink_rcv_msg+0x6d6/0xa90
 ? validate_linkmsg+0x540/0x540
 ? inet6_dump_ifmcaddr+0x10/0x10
 ? find_held_lock+0x6d/0xd0
 ? netlink_lookup.isra.42+0x428/0x730
 ? lock_acquire+0x350/0x350
 ? find_held_lock+0x6d/0xd0
 ? inet6_dump_ifmcaddr+0x10/0x10
 ? netlink_deliver_tap+0x124/0x5c0
 ? lock_acquire+0x350/0x350
 ? lockdep_rcu_suspicious+0x100/0x100
 ? netlink_lookup.isra.42+0x447/0x730
 ? rcu_is_watching+0x88/0xd0
 ? netlink_connect+0x1d0/0x1d0
 ? netlink_deliver_tap+0x143/0x5c0
 ? __might_fault+0x7d/0xe0
 ? iov_iter_advance+0x176/0x7d0
 ? netlink_getname+0x150/0x150
 netlink_rcv_skb+0xb6/0x1d0
 ? validate_linkmsg+0x540/0x540
 ? netlink_ack+0x4a0/0x4a0
 ? netlink_trim+0xda/0x1b0
 netlink_unicast+0x298/0x320
 ? netlink_detachskb+0x30/0x30
 ? __fget+0x410/0x410
 netlink_sendmsg+0x57e/0x630
 ? netlink_broadcast_filtered+0x8f0/0x8f0
 ? netlink_broadcast_filtered+0x8f0/0x8f0
 SYSC_sendto+0x296/0x320
 ? SYSC_connect+0x200/0x200
 ? __context_tracking_exit.part.4+0xe7/0x290
 ? cyc2ns_read_end+0x10/0x10
 ? lockdep_rcu_suspicious+0x100/0x100
 ? rcu_read_lock_sched_held+0x90/0xa0
 ? __context_tracking_exit.part.4+0x223/0x290
 ? stop_critical_timings+0x210/0x210
 ? SyS_socket+0xd6/0x120
 ? sock_create_kern+0x10/0x10
 ? mark_held_locks+0x1c/0x90
 ? do_syscall_64+0x110/0xc05
 ? SyS_getpeername+0x10/0x10
 do_syscall_64+0x1e5/0xc05
 ? syscall_return_slowpath+0x5b0/0x5b0
 ? lock_acquire+0x350/0x350
 ? lockdep_rcu_suspicious+0x100/0x100
 ? get_vtime_delta+0x15/0xf0
 ? get_vtime_delta+0x8b/0xf0
 ? vtime_user_enter+0x7f/0x90
 ? __context_tracking_enter+0x13c/0x2b0
 ? __context_tracking_enter+0x13c/0x2b0
 ? context_tracking_exit.part.5+0x40/0x40
 ? do_page_fault+0xb0/0x4d0
 ? rcu_is_watching+0x88/0xd0
 ? vmalloc_sync_all+0x20/0x20
 ? time_hardirqs_on+0x220/0x220
 ? prepare_exit_to_usermode+0x1d0/0x2a0
 ? enter_from_user_mode+0x30/0x30
 ? entry_SYSCALL_64_after_hwframe+0x18/0x2e
 ? trace_hardirqs_off_caller+0xc2/0x110
 ? trace_hardirqs_off_thunk+0x1a/0x1c
 entry_SYSCALL64_slow_path+0x25/0x25
RIP: 0033:0x7f204299f54d
RSP: 002b:00007ffc49024fd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000000000a RCX: 00007f204299f54d
RDX: 0000000000000018 RSI: 00007ffc49025010 RDI: 0000000000000012
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000012
R13: 00007ffc49029550 R14: 000055e31307a250 R15: 00007ffc49029530

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