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possible deadlock in flush_end_io

Status: upstream: reported on 2025/12/29 11:09
Subsystems: fs mm
[Documentation on labels]
Reported-by: syzbot+56189401febf7b380090@syzkaller.appspotmail.com
First crash: 68d, last: 5h21m
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [fs?] [mm?] possible deadlock in flush_end_io 0 (1) 2025/12/29 11:09

Sample crash report:
=====================================================
WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
syzkaller #0 Not tainted
-----------------------------------------------------
syz-executor/6573 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffff800097625150 (&p->sequence){+.-.}-{0:0}, at: __fprop_add_percpu_max+0x130/0x1f4 lib/flex_proportions.c:186

and this task is already holding:
ffff0000f7cd0940 (&xa->xa_lock#10){..-.}-{3:3}, at: __folio_end_writeback+0x10c/0x6f8 mm/page-writeback.c:2990
which would create a new lock dependency:
 (&xa->xa_lock#10){..-.}-{3:3} -> (&p->sequence){+.-.}-{0:0}

but this new dependency connects a HARDIRQ-irq-safe lock:
 (&fq->mq_flush_lock){-.-.}-{3:3}

... which became HARDIRQ-irq-safe at:
  lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
  __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
  _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
  flush_end_io+0xb4/0xd68 block/blk-flush.c:211
  __blk_mq_end_request+0x37c/0x57c block/blk-mq.c:1159
  blk_mq_end_request+0x68/0x88 block/blk-mq.c:1171
  nvme_end_req drivers/nvme/host/core.c:454 [inline]
  nvme_complete_rq+0x150/0x464 drivers/nvme/host/core.c:-1
  nvme_pci_complete_rq drivers/nvme/host/pci.c:1343 [inline]
  nvme_handle_cqe drivers/nvme/host/pci.c:1407 [inline]
  nvme_poll_cq+0x644/0x1018 drivers/nvme/host/pci.c:1434
  nvme_irq+0x90/0x240 drivers/nvme/host/pci.c:1448
  __handle_irq_event_percpu+0x20c/0x8e4 kernel/irq/handle.c:211
  handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
  handle_irq_event+0x9c/0x1d0 kernel/irq/handle.c:265
  handle_fasteoi_irq+0x328/0x8d8 kernel/irq/chip.c:764
  generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
  handle_irq_desc kernel/irq/irqdesc.c:669 [inline]
  generic_handle_domain_irq+0xe0/0x140 kernel/irq/irqdesc.c:725
  __gic_handle_irq drivers/irqchip/irq-gic-v3.c:825 [inline]
  __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:876 [inline]
  gic_handle_irq+0x6c/0x18c drivers/irqchip/irq-gic-v3.c:920
  call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891
  do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:135
  __el1_irq arch/arm64/kernel/entry-common.c:497 [inline]
  el1_interrupt+0x3c/0x60 arch/arm64/kernel/entry-common.c:510
  el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
  el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
  __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline]
  arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline]
  raw_spin_rq_unlock_irq kernel/sched/sched.h:1570 [inline]
  finish_lock_switch+0xb4/0x1c0 kernel/sched/core.c:4995
  finish_task_switch+0x104/0x5dc kernel/sched/core.c:5112
  context_switch kernel/sched/core.c:5259 [inline]
  __schedule+0x1254/0x2a7c kernel/sched/core.c:6863
  __schedule_loop kernel/sched/core.c:6945 [inline]
  schedule+0xb4/0x230 kernel/sched/core.c:6960
  schedule_hrtimeout_range_clock+0x19c/0x2b4 kernel/time/sleep_timeout.c:207
  schedule_hrtimeout_range+0x38/0x4c kernel/time/sleep_timeout.c:263
  ep_poll+0xa70/0xd38 fs/eventpoll.c:2028
  do_epoll_wait+0x194/0x204 fs/eventpoll.c:2461
  do_epoll_pwait+0x70/0x18c fs/eventpoll.c:2491
  __do_sys_epoll_pwait fs/eventpoll.c:2504 [inline]
  __se_sys_epoll_pwait fs/eventpoll.c:2498 [inline]
  __arm64_sys_epoll_pwait+0x1e0/0x234 fs/eventpoll.c:2498
  __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
  invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
  el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
  do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
  el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
  el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
  el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

to a HARDIRQ-irq-unsafe lock:
 (&p->sequence){+.-.}-{0:0}

... which became HARDIRQ-irq-unsafe at:
...
  lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
  do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline]
  do_write_seqcount_begin include/linux/seqlock.h:503 [inline]
  fprop_new_period+0x3b8/0x718 lib/flex_proportions.c:74
  writeout_period+0x94/0x11c mm/page-writeback.c:615
  call_timer_fn+0x19c/0x814 kernel/time/timer.c:1748
  expire_timers kernel/time/timer.c:1799 [inline]
  __run_timers kernel/time/timer.c:2373 [inline]
  __run_timer_base+0x51c/0x76c kernel/time/timer.c:2385
  run_timer_base kernel/time/timer.c:2394 [inline]
  run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2405
  handle_softirqs+0x31c/0xc88 kernel/softirq.c:622
  __do_softirq+0x14/0x20 kernel/softirq.c:656
  ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:68
  call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891
  do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:73
  invoke_softirq kernel/softirq.c:503 [inline]
  __irq_exit_rcu+0x1b0/0x478 kernel/softirq.c:723
  irq_exit_rcu+0x14/0x84 kernel/softirq.c:739
  __el1_irq arch/arm64/kernel/entry-common.c:498 [inline]
  el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:510
  el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
  el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
  __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline]
  arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline]
  __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
  _raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:194
  __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
  debug_check_no_obj_freed+0x454/0x470 lib/debugobjects.c:1129
  slab_free_hook mm/slub.c:2471 [inline]
  slab_free mm/slub.c:6668 [inline]
  kmem_cache_free+0x120/0x6e4 mm/slub.c:6779
  kfree_skbmem+0x14c/0x1dc net/core/skbuff.c:-1
  __kfree_skb net/core/skbuff.c:1197 [inline]
  consume_skb+0xb8/0x130 net/core/skbuff.c:1428
  netlink_broadcast_filtered+0xc60/0xde8 net/netlink/af_netlink.c:1535
  nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
  nlmsg_multicast include/net/netlink.h:1184 [inline]
  nlmsg_notify+0xfc/0x1e0 net/netlink/af_netlink.c:2593
  rtnl_notify+0xa0/0xd8 net/core/rtnetlink.c:958
  rtmsg_fib+0x21c/0x380 net/ipv4/fib_semantics.c:572
  fib_table_insert+0xa5c/0x1398 net/ipv4/fib_trie.c:1380
  fib_magic+0x250/0x31c net/ipv4/fib_frontend.c:1134
  fib_add_ifaddr+0x2ec/0x4f8 net/ipv4/fib_frontend.c:1171
  fib_inetaddr_event+0x114/0x1d0 net/ipv4/fib_frontend.c:1470
  notifier_call_chain+0x190/0x4cc kernel/notifier.c:85
  blocking_notifier_call_chain+0x70/0xa0 kernel/notifier.c:380
  __inet_insert_ifa+0x8a8/0xa98 net/ipv4/devinet.c:566
  inet_rtm_newaddr+0xde8/0x166c net/ipv4/devinet.c:1001
  rtnetlink_rcv_msg+0x664/0x97c net/core/rtnetlink.c:6958
  netlink_rcv_skb+0x220/0x3fc net/netlink/af_netlink.c:2550
  rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6985
  netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
  netlink_unicast+0x694/0x8c4 net/netlink/af_netlink.c:1344
  netlink_sendmsg+0x648/0x930 net/netlink/af_netlink.c:1894
  sock_sendmsg_nosec net/socket.c:727 [inline]
  __sock_sendmsg net/socket.c:742 [inline]
  __sys_sendto+0x36c/0x4f4 net/socket.c:2206
  __do_sys_sendto net/socket.c:2213 [inline]
  __se_sys_sendto net/socket.c:2209 [inline]
  __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2209
  __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
  invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
  el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
  do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
  el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
  el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
  el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

other info that might help us debug this:

Chain exists of:
  &fq->mq_flush_lock --> &xa->xa_lock#10 --> &p->sequence

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&p->sequence);
                               local_irq_disable();
                               lock(&fq->mq_flush_lock);
                               lock(&xa->xa_lock#10);
  <Interrupt>
    lock(&fq->mq_flush_lock);

 *** DEADLOCK ***

3 locks held by syz-executor/6573:
 #0: ffff0000db300420 (sb_writers#17){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
 #0: ffff0000db300420 (sb_writers#17){.+.+}-{0:0}, at: vfs_write+0x24c/0xa3c fs/read_write.c:682
 #1: ffff0000f7cd0d38 (&fi->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #1: ffff0000f7cd0d38 (&fi->lock){+.+.}-{3:3}, at: fuse_writepage_end+0x138/0x454 fs/fuse/file.c:2001
 #2: ffff0000f7cd0940 (&xa->xa_lock#10){..-.}-{3:3}, at: __folio_end_writeback+0x10c/0x6f8 mm/page-writeback.c:2990

the dependencies between HARDIRQ-irq-safe lock and the holding lock:
 -> (&fq->mq_flush_lock){-.-.}-{3:3} {
    IN-HARDIRQ-W at:
                      lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                      __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                      _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
                      flush_end_io+0xb4/0xd68 block/blk-flush.c:211
                      __blk_mq_end_request+0x37c/0x57c block/blk-mq.c:1159
                      blk_mq_end_request+0x68/0x88 block/blk-mq.c:1171
                      nvme_end_req drivers/nvme/host/core.c:454 [inline]
                      nvme_complete_rq+0x150/0x464 drivers/nvme/host/core.c:-1
                      nvme_pci_complete_rq drivers/nvme/host/pci.c:1343 [inline]
                      nvme_handle_cqe drivers/nvme/host/pci.c:1407 [inline]
                      nvme_poll_cq+0x644/0x1018 drivers/nvme/host/pci.c:1434
                      nvme_irq+0x90/0x240 drivers/nvme/host/pci.c:1448
                      __handle_irq_event_percpu+0x20c/0x8e4 kernel/irq/handle.c:211
                      handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
                      handle_irq_event+0x9c/0x1d0 kernel/irq/handle.c:265
                      handle_fasteoi_irq+0x328/0x8d8 kernel/irq/chip.c:764
                      generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
                      handle_irq_desc kernel/irq/irqdesc.c:669 [inline]
                      generic_handle_domain_irq+0xe0/0x140 kernel/irq/irqdesc.c:725
                      __gic_handle_irq drivers/irqchip/irq-gic-v3.c:825 [inline]
                      __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:876 [inline]
                      gic_handle_irq+0x6c/0x18c drivers/irqchip/irq-gic-v3.c:920
                      call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891
                      do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:135
                      __el1_irq arch/arm64/kernel/entry-common.c:497 [inline]
                      el1_interrupt+0x3c/0x60 arch/arm64/kernel/entry-common.c:510
                      el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
                      el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
                      __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline]
                      arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline]
                      raw_spin_rq_unlock_irq kernel/sched/sched.h:1570 [inline]
                      finish_lock_switch+0xb4/0x1c0 kernel/sched/core.c:4995
                      finish_task_switch+0x104/0x5dc kernel/sched/core.c:5112
                      context_switch kernel/sched/core.c:5259 [inline]
                      __schedule+0x1254/0x2a7c kernel/sched/core.c:6863
                      __schedule_loop kernel/sched/core.c:6945 [inline]
                      schedule+0xb4/0x230 kernel/sched/core.c:6960
                      schedule_hrtimeout_range_clock+0x19c/0x2b4 kernel/time/sleep_timeout.c:207
                      schedule_hrtimeout_range+0x38/0x4c kernel/time/sleep_timeout.c:263
                      ep_poll+0xa70/0xd38 fs/eventpoll.c:2028
                      do_epoll_wait+0x194/0x204 fs/eventpoll.c:2461
                      do_epoll_pwait+0x70/0x18c fs/eventpoll.c:2491
                      __do_sys_epoll_pwait fs/eventpoll.c:2504 [inline]
                      __se_sys_epoll_pwait fs/eventpoll.c:2498 [inline]
                      __arm64_sys_epoll_pwait+0x1e0/0x234 fs/eventpoll.c:2498
                      __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
                      invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
                      el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
                      do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
                      el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
                      el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
                      el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
    IN-SOFTIRQ-W at:
                      lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                      __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                      _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
                      flush_end_io+0xb4/0xd68 block/blk-flush.c:211
                      __blk_mq_end_request+0x37c/0x57c block/blk-mq.c:1159
                      blk_mq_end_request+0x68/0x88 block/blk-mq.c:1171
                      nvme_end_req drivers/nvme/host/core.c:454 [inline]
                      nvme_complete_rq+0x150/0x464 drivers/nvme/host/core.c:-1
                      nvme_pci_complete_rq drivers/nvme/host/pci.c:1343 [inline]
                      nvme_handle_cqe drivers/nvme/host/pci.c:1407 [inline]
                      nvme_poll_cq+0x644/0x1018 drivers/nvme/host/pci.c:1434
                      nvme_irq+0x90/0x240 drivers/nvme/host/pci.c:1448
                      __handle_irq_event_percpu+0x20c/0x8e4 kernel/irq/handle.c:211
                      handle_irq_event_percpu kernel/irq/handle.c:248 [inline]
                      handle_irq_event+0x9c/0x1d0 kernel/irq/handle.c:265
                      handle_fasteoi_irq+0x328/0x8d8 kernel/irq/chip.c:764
                      generic_handle_irq_desc include/linux/irqdesc.h:172 [inline]
                      handle_irq_desc kernel/irq/irqdesc.c:669 [inline]
                      generic_handle_domain_irq+0xe0/0x140 kernel/irq/irqdesc.c:725
                      __gic_handle_irq drivers/irqchip/irq-gic-v3.c:825 [inline]
                      __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:876 [inline]
                      gic_handle_irq+0x6c/0x18c drivers/irqchip/irq-gic-v3.c:920
                      do_interrupt_handler+0xe0/0x138 arch/arm64/kernel/entry-common.c:137
                      __el1_irq arch/arm64/kernel/entry-common.c:497 [inline]
                      el1_interrupt+0x3c/0x60 arch/arm64/kernel/entry-common.c:510
                      el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
                      el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
                      __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline]
                      arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline]
                      handle_softirqs+0x1f8/0xc88 kernel/softirq.c:606
                      __do_softirq+0x14/0x20 kernel/softirq.c:656
                      ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:68
                      call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891
                      do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:73
                      invoke_softirq kernel/softirq.c:503 [inline]
                      __irq_exit_rcu+0x1b0/0x478 kernel/softirq.c:723
                      irq_exit_rcu+0x14/0x84 kernel/softirq.c:739
                      __el1_irq arch/arm64/kernel/entry-common.c:498 [inline]
                      el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:510
                      el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
                      el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
                      __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline]
                      arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline]
                      __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
                      _raw_spin_unlock_irq+0x34/0x80 kernel/locking/spinlock.c:202
                      do_wait_for_common+0x27c/0x3f8 kernel/sched/completion.c:99
                      __wait_for_common kernel/sched/completion.c:121 [inline]
                      wait_for_common_io kernel/sched/completion.c:138 [inline]
                      wait_for_completion_io_timeout+0x48/0x68 kernel/sched/completion.c:206
                      blk_wait_io block/blk.h:102 [inline]
                      submit_bio_wait+0x154/0x208 block/bio.c:1392
                      blkdev_issue_flush+0xb4/0x100 block/blk-flush.c:473
                      ext4_sync_file+0x61c/0xb2c fs/ext4/fsync.c:167
                      vfs_fsync_range fs/sync.c:188 [inline]
                      vfs_fsync+0x154/0x18c fs/sync.c:202
                      iomap_swapfile_activate+0x14c/0x9a8 fs/iomap/swapfile.c:162
                      ext4_iomap_swap_activate+0x3c/0x50 fs/ext4/inode.c:3972
                      setup_swap_extents+0x158/0x568 mm/swapfile.c:2688
                      __do_sys_swapon mm/swapfile.c:3488 [inline]
                      __se_sys_swapon mm/swapfile.c:3392 [inline]
                      __arm64_sys_swapon+0xea8/0x1a38 mm/swapfile.c:3392
                      __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
                      invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
                      el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
                      do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
                      el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
                      el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
                      el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
    INITIAL USE at:
                     lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                     __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
                     _raw_spin_lock_irq+0x58/0x70 kernel/locking/spinlock.c:170
                     spin_lock_irq include/linux/spinlock.h:376 [inline]
                     blk_insert_flush+0x360/0x4b8 block/blk-flush.c:454
                     blk_mq_submit_bio+0x1668/0x21e8 block/blk-mq.c:3229
                     __submit_bio+0x1d8/0x4d8 block/blk-core.c:637
                     __submit_bio_noacct_mq block/blk-core.c:724 [inline]
                     submit_bio_noacct_nocheck+0x274/0x990 block/blk-core.c:755
                     submit_bio_noacct+0xdc0/0x186c block/blk-core.c:879
                     submit_bio+0x3b4/0x550 block/blk-core.c:921
                     submit_bio_wait+0x104/0x208 block/bio.c:1391
                     blkdev_issue_flush+0xb4/0x100 block/blk-flush.c:473
                     ext4_init_inode_table+0x420/0x780 fs/ext4/ialloc.c:1602
                     ext4_run_li_request fs/ext4/super.c:3732 [inline]
                     ext4_lazyinit_thread+0x6dc/0x1730 fs/ext4/super.c:3827
                     kthread+0x5fc/0x75c kernel/kthread.c:463
                     ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844
  }
  ... key      at: [<ffff8000977c83c0>] blk_alloc_flush_queue.__key+0x0/0x20
-> (&xa->xa_lock#10){..-.}-{3:3} {
   IN-SOFTIRQ-W at:
                    lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                    __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                    _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
                    __folio_end_writeback+0x10c/0x6f8 mm/page-writeback.c:2990
                    folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1661
                    folio_end_writeback+0xd8/0x248 mm/filemap.c:1687
                    end_buffer_async_write+0x20c/0x350 fs/buffer.c:419
                    end_bio_bh_io_sync+0xb0/0x184 fs/buffer.c:2776
                    bio_endio+0x8d4/0x910 block/bio.c:1675
                    blk_update_request+0x474/0xba8 block/blk-mq.c:1007
                    blk_mq_end_request+0x54/0x88 block/blk-mq.c:1169
                    lo_complete_rq+0x124/0x274 drivers/block/loop.c:314
                    blk_complete_reqs block/blk-mq.c:1244 [inline]
                    blk_done_softirq+0x11c/0x168 block/blk-mq.c:1249
                    handle_softirqs+0x31c/0xc88 kernel/softirq.c:622
                    run_ksoftirqd+0x70/0xc0 kernel/softirq.c:1063
                    smpboot_thread_fn+0x4d8/0x9cc kernel/smpboot.c:160
                    kthread+0x5fc/0x75c kernel/kthread.c:463
                    ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844
   INITIAL USE at:
                   lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                   __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
                   _raw_spin_lock_irq+0x58/0x70 kernel/locking/spinlock.c:170
                   spin_lock_irq include/linux/spinlock.h:376 [inline]
                   shmem_add_to_page_cache+0x564/0xa24 mm/shmem.c:904
                   shmem_alloc_and_add_folio+0x758/0x10c4 mm/shmem.c:1958
                   shmem_get_folio_gfp+0x4d4/0x159c mm/shmem.c:2556
                   shmem_read_folio_gfp+0x8c/0xf0 mm/shmem.c:5974
                   drm_gem_get_pages+0x1cc/0x7c0 drivers/gpu/drm/drm_gem.c:654
                   drm_gem_shmem_get_pages_locked+0x1d4/0x364 drivers/gpu/drm/drm_gem_shmem_helper.c:239
                   drm_gem_shmem_pin_locked+0x1f8/0x410 drivers/gpu/drm/drm_gem_shmem_helper.c:300
                   drm_gem_shmem_vmap_locked+0x3cc/0x658 drivers/gpu/drm/drm_gem_shmem_helper.c:404
                   drm_gem_shmem_object_vmap+0x28/0x38 include/drm/drm_gem_shmem_helper.h:245
                   drm_gem_vmap_locked drivers/gpu/drm/drm_gem.c:1269 [inline]
                   drm_gem_vmap+0x104/0x1d8 drivers/gpu/drm/drm_gem.c:1311
                   drm_client_buffer_vmap+0x68/0xb0 drivers/gpu/drm/drm_client.c:355
                   drm_fbdev_shmem_driver_fbdev_probe+0x1f4/0x700 drivers/gpu/drm/drm_fbdev_shmem.c:159
                   drm_fb_helper_single_fb_probe drivers/gpu/drm/drm_fb_helper.c:1562 [inline]
                   __drm_fb_helper_initial_config_and_unlock+0x108c/0x1728 drivers/gpu/drm/drm_fb_helper.c:1741
                   drm_fb_helper_initial_config+0x3c/0x58 drivers/gpu/drm/drm_fb_helper.c:1828
                   drm_fbdev_client_hotplug+0x154/0x22c drivers/gpu/drm/clients/drm_fbdev_client.c:66
                   drm_client_register+0x13c/0x1d4 drivers/gpu/drm/drm_client.c:143
                   drm_fbdev_client_setup+0x194/0x3d0 drivers/gpu/drm/clients/drm_fbdev_client.c:168
                   drm_client_setup+0x114/0x228 drivers/gpu/drm/clients/drm_client_setup.c:46
                   vkms_create+0x370/0x420 drivers/gpu/drm/vkms/vkms_drv.c:211
                   vkms_init+0x64/0x9c drivers/gpu/drm/vkms/vkms_drv.c:239
                   do_one_initcall+0x248/0x9b4 init/main.c:1378
                   do_initcall_level+0x128/0x1c4 init/main.c:1440
                   do_initcalls+0x70/0xd0 init/main.c:1456
                   do_basic_setup+0x78/0x8c init/main.c:1475
                   kernel_init_freeable+0x268/0x39c init/main.c:1688
                   kernel_init+0x24/0x1dc init/main.c:1578
                   ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844
 }
 ... key      at: [<ffff800097649620>] xa_init_flags.__key+0x0/0x20
 ... acquired at:
   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
   _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
   __folio_end_writeback+0x10c/0x6f8 mm/page-writeback.c:2990
   folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1661
   folio_end_writeback+0xd8/0x248 mm/filemap.c:1687
   f2fs_write_end_io+0x6c0/0xa78 fs/f2fs/data.c:362
   bio_endio+0x8d4/0x910 block/bio.c:1675
   blk_update_request+0x474/0xba8 block/blk-mq.c:1007
   blk_mq_end_request+0x54/0x88 block/blk-mq.c:1169
   blk_flush_complete_seq+0x57c/0xad4 block/blk-flush.c:191
   flush_end_io+0x9e8/0xd68 block/blk-flush.c:250
   __blk_mq_end_request+0x37c/0x57c block/blk-mq.c:1159
   blk_mq_end_request+0x68/0x88 block/blk-mq.c:1171
   lo_complete_rq+0x124/0x274 drivers/block/loop.c:314
   blk_complete_reqs block/blk-mq.c:1244 [inline]
   blk_done_softirq+0x11c/0x168 block/blk-mq.c:1249
   handle_softirqs+0x31c/0xc88 kernel/softirq.c:622
   run_ksoftirqd+0x70/0xc0 kernel/softirq.c:1063
   smpboot_thread_fn+0x4d8/0x9cc kernel/smpboot.c:160
   kthread+0x5fc/0x75c kernel/kthread.c:463
   ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844


the dependencies between the lock to be acquired
 and HARDIRQ-irq-unsafe lock:
-> (&p->sequence){+.-.}-{0:0} {
   HARDIRQ-ON-W at:
                    lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                    do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline]
                    do_write_seqcount_begin include/linux/seqlock.h:503 [inline]
                    fprop_new_period+0x3b8/0x718 lib/flex_proportions.c:74
                    writeout_period+0x94/0x11c mm/page-writeback.c:615
                    call_timer_fn+0x19c/0x814 kernel/time/timer.c:1748
                    expire_timers kernel/time/timer.c:1799 [inline]
                    __run_timers kernel/time/timer.c:2373 [inline]
                    __run_timer_base+0x51c/0x76c kernel/time/timer.c:2385
                    run_timer_base kernel/time/timer.c:2394 [inline]
                    run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2405
                    handle_softirqs+0x31c/0xc88 kernel/softirq.c:622
                    __do_softirq+0x14/0x20 kernel/softirq.c:656
                    ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:68
                    call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891
                    do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:73
                    invoke_softirq kernel/softirq.c:503 [inline]
                    __irq_exit_rcu+0x1b0/0x478 kernel/softirq.c:723
                    irq_exit_rcu+0x14/0x84 kernel/softirq.c:739
                    __el1_irq arch/arm64/kernel/entry-common.c:498 [inline]
                    el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:510
                    el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
                    el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
                    __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline]
                    arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline]
                    __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
                    _raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:194
                    __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
                    debug_check_no_obj_freed+0x454/0x470 lib/debugobjects.c:1129
                    slab_free_hook mm/slub.c:2471 [inline]
                    slab_free mm/slub.c:6668 [inline]
                    kmem_cache_free+0x120/0x6e4 mm/slub.c:6779
                    kfree_skbmem+0x14c/0x1dc net/core/skbuff.c:-1
                    __kfree_skb net/core/skbuff.c:1197 [inline]
                    consume_skb+0xb8/0x130 net/core/skbuff.c:1428
                    netlink_broadcast_filtered+0xc60/0xde8 net/netlink/af_netlink.c:1535
                    nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
                    nlmsg_multicast include/net/netlink.h:1184 [inline]
                    nlmsg_notify+0xfc/0x1e0 net/netlink/af_netlink.c:2593
                    rtnl_notify+0xa0/0xd8 net/core/rtnetlink.c:958
                    rtmsg_fib+0x21c/0x380 net/ipv4/fib_semantics.c:572
                    fib_table_insert+0xa5c/0x1398 net/ipv4/fib_trie.c:1380
                    fib_magic+0x250/0x31c net/ipv4/fib_frontend.c:1134
                    fib_add_ifaddr+0x2ec/0x4f8 net/ipv4/fib_frontend.c:1171
                    fib_inetaddr_event+0x114/0x1d0 net/ipv4/fib_frontend.c:1470
                    notifier_call_chain+0x190/0x4cc kernel/notifier.c:85
                    blocking_notifier_call_chain+0x70/0xa0 kernel/notifier.c:380
                    __inet_insert_ifa+0x8a8/0xa98 net/ipv4/devinet.c:566
                    inet_rtm_newaddr+0xde8/0x166c net/ipv4/devinet.c:1001
                    rtnetlink_rcv_msg+0x664/0x97c net/core/rtnetlink.c:6958
                    netlink_rcv_skb+0x220/0x3fc net/netlink/af_netlink.c:2550
                    rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6985
                    netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
                    netlink_unicast+0x694/0x8c4 net/netlink/af_netlink.c:1344
                    netlink_sendmsg+0x648/0x930 net/netlink/af_netlink.c:1894
                    sock_sendmsg_nosec net/socket.c:727 [inline]
                    __sock_sendmsg net/socket.c:742 [inline]
                    __sys_sendto+0x36c/0x4f4 net/socket.c:2206
                    __do_sys_sendto net/socket.c:2213 [inline]
                    __se_sys_sendto net/socket.c:2209 [inline]
                    __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2209
                    __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
                    invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
                    el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
                    do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
                    el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
                    el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
                    el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
   IN-SOFTIRQ-W at:
                    lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                    do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline]
                    do_write_seqcount_begin include/linux/seqlock.h:503 [inline]
                    fprop_new_period+0x3b8/0x718 lib/flex_proportions.c:74
                    writeout_period+0x94/0x11c mm/page-writeback.c:615
                    call_timer_fn+0x19c/0x814 kernel/time/timer.c:1748
                    expire_timers kernel/time/timer.c:1799 [inline]
                    __run_timers kernel/time/timer.c:2373 [inline]
                    __run_timer_base+0x51c/0x76c kernel/time/timer.c:2385
                    run_timer_base kernel/time/timer.c:2394 [inline]
                    run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2405
                    handle_softirqs+0x31c/0xc88 kernel/softirq.c:622
                    __do_softirq+0x14/0x20 kernel/softirq.c:656
                    ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:68
                    call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891
                    do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:73
                    invoke_softirq kernel/softirq.c:503 [inline]
                    __irq_exit_rcu+0x1b0/0x478 kernel/softirq.c:723
                    irq_exit_rcu+0x14/0x84 kernel/softirq.c:739
                    __el1_irq arch/arm64/kernel/entry-common.c:498 [inline]
                    el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:510
                    el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
                    el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
                    __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline]
                    arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline]
                    __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
                    _raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:194
                    __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
                    debug_check_no_obj_freed+0x454/0x470 lib/debugobjects.c:1129
                    slab_free_hook mm/slub.c:2471 [inline]
                    slab_free mm/slub.c:6668 [inline]
                    kmem_cache_free+0x120/0x6e4 mm/slub.c:6779
                    kfree_skbmem+0x14c/0x1dc net/core/skbuff.c:-1
                    __kfree_skb net/core/skbuff.c:1197 [inline]
                    consume_skb+0xb8/0x130 net/core/skbuff.c:1428
                    netlink_broadcast_filtered+0xc60/0xde8 net/netlink/af_netlink.c:1535
                    nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
                    nlmsg_multicast include/net/netlink.h:1184 [inline]
                    nlmsg_notify+0xfc/0x1e0 net/netlink/af_netlink.c:2593
                    rtnl_notify+0xa0/0xd8 net/core/rtnetlink.c:958
                    rtmsg_fib+0x21c/0x380 net/ipv4/fib_semantics.c:572
                    fib_table_insert+0xa5c/0x1398 net/ipv4/fib_trie.c:1380
                    fib_magic+0x250/0x31c net/ipv4/fib_frontend.c:1134
                    fib_add_ifaddr+0x2ec/0x4f8 net/ipv4/fib_frontend.c:1171
                    fib_inetaddr_event+0x114/0x1d0 net/ipv4/fib_frontend.c:1470
                    notifier_call_chain+0x190/0x4cc kernel/notifier.c:85
                    blocking_notifier_call_chain+0x70/0xa0 kernel/notifier.c:380
                    __inet_insert_ifa+0x8a8/0xa98 net/ipv4/devinet.c:566
                    inet_rtm_newaddr+0xde8/0x166c net/ipv4/devinet.c:1001
                    rtnetlink_rcv_msg+0x664/0x97c net/core/rtnetlink.c:6958
                    netlink_rcv_skb+0x220/0x3fc net/netlink/af_netlink.c:2550
                    rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6985
                    netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
                    netlink_unicast+0x694/0x8c4 net/netlink/af_netlink.c:1344
                    netlink_sendmsg+0x648/0x930 net/netlink/af_netlink.c:1894
                    sock_sendmsg_nosec net/socket.c:727 [inline]
                    __sock_sendmsg net/socket.c:742 [inline]
                    __sys_sendto+0x36c/0x4f4 net/socket.c:2206
                    __do_sys_sendto net/socket.c:2213 [inline]
                    __se_sys_sendto net/socket.c:2209 [inline]
                    __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2209
                    __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
                    invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
                    el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
                    do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
                    el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
                    el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
                    el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
   INITIAL USE at:
                   lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                   do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline]
                   do_write_seqcount_begin include/linux/seqlock.h:503 [inline]
                   fprop_new_period+0x3b8/0x718 lib/flex_proportions.c:74
                   writeout_period+0x94/0x11c mm/page-writeback.c:615
                   call_timer_fn+0x19c/0x814 kernel/time/timer.c:1748
                   expire_timers kernel/time/timer.c:1799 [inline]
                   __run_timers kernel/time/timer.c:2373 [inline]
                   __run_timer_base+0x51c/0x76c kernel/time/timer.c:2385
                   run_timer_base kernel/time/timer.c:2394 [inline]
                   run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2405
                   handle_softirqs+0x31c/0xc88 kernel/softirq.c:622
                   __do_softirq+0x14/0x20 kernel/softirq.c:656
                   ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:68
                   call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891
                   do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:73
                   invoke_softirq kernel/softirq.c:503 [inline]
                   __irq_exit_rcu+0x1b0/0x478 kernel/softirq.c:723
                   irq_exit_rcu+0x14/0x84 kernel/softirq.c:739
                   __el1_irq arch/arm64/kernel/entry-common.c:498 [inline]
                   el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:510
                   el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:515
                   el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:592
                   __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline]
                   arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline]
                   __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
                   _raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:194
                   __debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
                   debug_check_no_obj_freed+0x454/0x470 lib/debugobjects.c:1129
                   slab_free_hook mm/slub.c:2471 [inline]
                   slab_free mm/slub.c:6668 [inline]
                   kmem_cache_free+0x120/0x6e4 mm/slub.c:6779
                   kfree_skbmem+0x14c/0x1dc net/core/skbuff.c:-1
                   __kfree_skb net/core/skbuff.c:1197 [inline]
                   consume_skb+0xb8/0x130 net/core/skbuff.c:1428
                   netlink_broadcast_filtered+0xc60/0xde8 net/netlink/af_netlink.c:1535
                   nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
                   nlmsg_multicast include/net/netlink.h:1184 [inline]
                   nlmsg_notify+0xfc/0x1e0 net/netlink/af_netlink.c:2593
                   rtnl_notify+0xa0/0xd8 net/core/rtnetlink.c:958
                   rtmsg_fib+0x21c/0x380 net/ipv4/fib_semantics.c:572
                   fib_table_insert+0xa5c/0x1398 net/ipv4/fib_trie.c:1380
                   fib_magic+0x250/0x31c net/ipv4/fib_frontend.c:1134
                   fib_add_ifaddr+0x2ec/0x4f8 net/ipv4/fib_frontend.c:1171
                   fib_inetaddr_event+0x114/0x1d0 net/ipv4/fib_frontend.c:1470
                   notifier_call_chain+0x190/0x4cc kernel/notifier.c:85
                   blocking_notifier_call_chain+0x70/0xa0 kernel/notifier.c:380
                   __inet_insert_ifa+0x8a8/0xa98 net/ipv4/devinet.c:566
                   inet_rtm_newaddr+0xde8/0x166c net/ipv4/devinet.c:1001
                   rtnetlink_rcv_msg+0x664/0x97c net/core/rtnetlink.c:6958
                   netlink_rcv_skb+0x220/0x3fc net/netlink/af_netlink.c:2550
                   rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6985
                   netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
                   netlink_unicast+0x694/0x8c4 net/netlink/af_netlink.c:1344
                   netlink_sendmsg+0x648/0x930 net/netlink/af_netlink.c:1894
                   sock_sendmsg_nosec net/socket.c:727 [inline]
                   __sock_sendmsg net/socket.c:742 [inline]
                   __sys_sendto+0x36c/0x4f4 net/socket.c:2206
                   __do_sys_sendto net/socket.c:2213 [inline]
                   __se_sys_sendto net/socket.c:2209 [inline]
                   __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2209
                   __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
                   invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
                   el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
                   do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
                   el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
                   el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
                   el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
   INITIAL READ USE at:
                        lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
                        seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline]
                        fprop_fraction_percpu+0xac/0x270 lib/flex_proportions.c:155
                        __wb_calc_thresh+0xfc/0x3b0 mm/page-writeback.c:913
                        wb_bg_dirty_limits mm/page-writeback.c:2130 [inline]
                        domain_over_bg_thresh+0xb8/0x1f0 mm/page-writeback.c:2144
                        wb_over_bg_thresh+0xf8/0x17c mm/page-writeback.c:2165
                        wb_check_background_flush fs/fs-writeback.c:2278 [inline]
                        wb_do_writeback fs/fs-writeback.c:2376 [inline]
                        wb_workfn+0xa30/0xdc0 fs/fs-writeback.c:2403
                        process_one_work+0x7c0/0x1558 kernel/workqueue.c:3257
                        process_scheduled_works kernel/workqueue.c:3340 [inline]
                        worker_thread+0x958/0xed8 kernel/workqueue.c:3421
                        kthread+0x5fc/0x75c kernel/kthread.c:463
                        ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844
 }
 ... key      at: [<ffff800097b99300>] fprop_global_init.__key.1+0x0/0x20
 ... acquired at:
   seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline]
   fprop_fraction_percpu+0xf0/0x270 lib/flex_proportions.c:155
   __fprop_add_percpu_max+0x130/0x1f4 lib/flex_proportions.c:186
   wb_domain_writeout_add mm/page-writeback.c:562 [inline]
   __wb_writeout_add+0xbc/0x27c mm/page-writeback.c:586
   __folio_end_writeback+0x380/0x6f8 mm/page-writeback.c:2997
   folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1661
   folio_end_writeback+0xd8/0x248 mm/filemap.c:1687
   iomap_finish_folio_write+0x1c0/0x2a4 fs/iomap/buffered-io.c:1713
   fuse_writepage_finish fs/fuse/file.c:1903 [inline]
   fuse_writepage_end+0x238/0x454 fs/fuse/file.c:2003
   fuse_request_end+0x898/0xc10 fs/fuse/dev.c:507
   fuse_dev_end_requests fs/fuse/dev.c:2415 [inline]
   fuse_abort_conn+0xe88/0x10a0 fs/fuse/dev.c:2513
   fuse_conn_abort_write+0x10c/0x194 fs/fuse/control.c:42
   vfs_write+0x2b8/0xa3c fs/read_write.c:684
   ksys_write+0x120/0x210 fs/read_write.c:738
   __do_sys_write fs/read_write.c:749 [inline]
   __se_sys_write fs/read_write.c:746 [inline]
   __arm64_sys_write+0x7c/0x90 fs/read_write.c:746
   __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
   invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
   el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
   do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
   el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
   el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
   el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596


stack backtrace:
CPU: 1 UID: 0 PID: 6573 Comm: syz-executor Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 print_bad_irq_dependency kernel/locking/lockdep.c:2616 [inline]
 check_irq_usage kernel/locking/lockdep.c:2857 [inline]
 check_prev_add kernel/locking/lockdep.c:3169 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x3058/0x30a4 kernel/locking/lockdep.c:5237
 lock_acquire+0x140/0x2e0 kernel/locking/lockdep.c:5868
 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline]
 fprop_fraction_percpu+0xf0/0x270 lib/flex_proportions.c:155
 __fprop_add_percpu_max+0x130/0x1f4 lib/flex_proportions.c:186
 wb_domain_writeout_add mm/page-writeback.c:562 [inline]
 __wb_writeout_add+0xbc/0x27c mm/page-writeback.c:586
 __folio_end_writeback+0x380/0x6f8 mm/page-writeback.c:2997
 folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1661
 folio_end_writeback+0xd8/0x248 mm/filemap.c:1687
 iomap_finish_folio_write+0x1c0/0x2a4 fs/iomap/buffered-io.c:1713
 fuse_writepage_finish fs/fuse/file.c:1903 [inline]
 fuse_writepage_end+0x238/0x454 fs/fuse/file.c:2003
 fuse_request_end+0x898/0xc10 fs/fuse/dev.c:507
 fuse_dev_end_requests fs/fuse/dev.c:2415 [inline]
 fuse_abort_conn+0xe88/0x10a0 fs/fuse/dev.c:2513
 fuse_conn_abort_write+0x10c/0x194 fs/fuse/control.c:42
 vfs_write+0x2b8/0xa3c fs/read_write.c:684
 ksys_write+0x120/0x210 fs/read_write.c:738
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:746
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Crashes (245):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/29 14:15 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/29 05:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/28 06:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/28 05:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/28 04:15 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/27 10:43 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/27 07:59 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/26 23:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/26 10:05 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/26 07:26 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/26 03:10 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/25 22:29 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/25 15:43 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/25 13:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/25 07:32 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/25 02:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/24 12:01 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/24 09:23 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/23 18:02 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/23 04:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/22 20:54 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/22 16:07 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/22 12:55 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/21 13:08 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/21 07:47 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/20 07:03 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/20 04:59 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/19 22:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/19 19:00 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/19 13:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/18 23:18 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/18 22:08 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/18 19:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/18 12:15 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/16 13:10 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 8f0b4cce4481 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/15 06:40 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/15 05:07 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/15 03:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/14 23:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/14 07:41 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/14 06:10 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/13 09:52 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/13 07:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/13 01:27 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/12/12 21:16 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/10/26 03:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci b98c94eed4a9 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/10/22 07:17 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 143937ca51cc 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
2025/10/22 07:17 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 143937ca51cc 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 possible deadlock in flush_end_io
* Struck through repros no longer work on HEAD.