===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected syzkaller #0 Not tainted ----------------------------------------------------- ksoftirqd/1/23 [HC0[0]:SC1[1]:HE0:SE0] is trying to acquire: ffff0000f8e78240 (&xa->xa_lock#10){..-.}-{3:3}, at: __folio_end_writeback+0x10c/0x75c mm/page-writeback.c:2996 and this task is already holding: ffff0000ca300518 (&fq->mq_flush_lock){-.-.}-{3:3}, at: flush_end_io+0xb4/0xd68 block/blk-flush.c:211 which would create a new lock dependency: (&fq->mq_flush_lock){-.-.}-{3:3} -> (&xa->xa_lock#10){..-.}-{3:3} but this new dependency connects a HARDIRQ-irq-safe lock: (&fq->mq_flush_lock){-.-.}-{3:3} ... which became HARDIRQ-irq-safe at: lock_acquire+0x14c/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:1150 blk_mq_end_request+0x68/0x88 block/blk-mq.c:1162 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:1265 [inline] nvme_handle_cqe drivers/nvme/host/pci.c:1329 [inline] nvme_poll_cq+0x65c/0x1018 drivers/nvme/host/pci.c:1356 nvme_irq+0x90/0x240 drivers/nvme/host/pci.c:1370 __handle_irq_event_percpu+0x224/0x8e4 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0x9c/0x1d0 kernel/irq/handle.c:257 handle_fasteoi_irq+0x328/0x8d8 kernel/irq/chip.c:764 generic_handle_irq_desc include/linux/irqdesc.h:173 [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:874 [inline] __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:925 [inline] gic_handle_irq+0x6c/0x190 drivers/irqchip/irq-gic-v3.c:969 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:157 __el1_irq arch/arm64/kernel/entry-common.c:519 [inline] el1_interrupt+0x3c/0x60 arch/arm64/kernel/entry-common.c:532 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:537 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:1558 [inline] finish_lock_switch+0xb4/0x1c0 kernel/sched/core.c:5073 finish_task_switch+0x120/0x5a4 kernel/sched/core.c:5191 context_switch kernel/sched/core.c:5328 [inline] __schedule+0x13b4/0x2864 kernel/sched/core.c:6929 preempt_schedule_common+0xe0/0x194 kernel/sched/core.c:7113 preempt_schedule+0x60/0x80 kernel/sched/core.c:7137 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x7c/0x80 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] blk_insert_flush+0x37c/0x4b8 block/blk-flush.c:456 blk_mq_submit_bio+0x1614/0x2168 block/blk-mq.c:3218 __submit_bio+0x1d8/0x4d8 block/blk-core.c:637 __submit_bio_noacct_mq block/blk-core.c:724 [inline] submit_bio_noacct_nocheck+0x29c/0x9a4 block/blk-core.c:755 submit_bio_noacct+0xde0/0x186c block/blk-core.c:879 submit_bio+0x3b4/0x550 block/blk-core.c:921 submit_bio_wait+0x104/0x208 block/bio.c:1388 blkdev_issue_flush+0xb4/0x100 block/blk-flush.c:473 ext4_init_inode_table+0x420/0x780 fs/ext4/ialloc.c:1603 ext4_run_li_request fs/ext4/super.c:3729 [inline] ext4_lazyinit_thread+0x704/0x1744 fs/ext4/super.c:3824 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 to a HARDIRQ-irq-unsafe lock: (&p->sequence){+.-.}-{0:0} ... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0x14c/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+0x1b4/0x818 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x51c/0x76c kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2404 handle_softirqs+0x328/0xc88 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:520 [inline] el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:532 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:537 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 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __uart_port_unlock_irqrestore include/linux/serial_core.h:616 [inline] pl011_console_device_unlock+0x90/0xc8 drivers/tty/serial/amba-pl011.c:2603 nbcon_emit_one kernel/printk/nbcon.c:1142 [inline] nbcon_kthread_func+0x58c/0x6d0 kernel/printk/nbcon.c:1229 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 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); lock(&fq->mq_flush_lock); *** DEADLOCK *** 1 lock held by ksoftirqd/1/23: #0: ffff0000ca300518 (&fq->mq_flush_lock){-.-.}-{3:3}, at: flush_end_io+0xb4/0xd68 block/blk-flush.c:211 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&fq->mq_flush_lock){-.-.}-{3:3} { IN-HARDIRQ-W at: lock_acquire+0x14c/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:1150 blk_mq_end_request+0x68/0x88 block/blk-mq.c:1162 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:1265 [inline] nvme_handle_cqe drivers/nvme/host/pci.c:1329 [inline] nvme_poll_cq+0x65c/0x1018 drivers/nvme/host/pci.c:1356 nvme_irq+0x90/0x240 drivers/nvme/host/pci.c:1370 __handle_irq_event_percpu+0x224/0x8e4 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0x9c/0x1d0 kernel/irq/handle.c:257 handle_fasteoi_irq+0x328/0x8d8 kernel/irq/chip.c:764 generic_handle_irq_desc include/linux/irqdesc.h:173 [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:874 [inline] __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:925 [inline] gic_handle_irq+0x6c/0x190 drivers/irqchip/irq-gic-v3.c:969 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:157 __el1_irq arch/arm64/kernel/entry-common.c:519 [inline] el1_interrupt+0x3c/0x60 arch/arm64/kernel/entry-common.c:532 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:537 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:1558 [inline] finish_lock_switch+0xb4/0x1c0 kernel/sched/core.c:5073 finish_task_switch+0x120/0x5a4 kernel/sched/core.c:5191 context_switch kernel/sched/core.c:5328 [inline] __schedule+0x13b4/0x2864 kernel/sched/core.c:6929 preempt_schedule_common+0xe0/0x194 kernel/sched/core.c:7113 preempt_schedule+0x60/0x80 kernel/sched/core.c:7137 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irq+0x7c/0x80 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:401 [inline] blk_insert_flush+0x37c/0x4b8 block/blk-flush.c:456 blk_mq_submit_bio+0x1614/0x2168 block/blk-mq.c:3218 __submit_bio+0x1d8/0x4d8 block/blk-core.c:637 __submit_bio_noacct_mq block/blk-core.c:724 [inline] submit_bio_noacct_nocheck+0x29c/0x9a4 block/blk-core.c:755 submit_bio_noacct+0xde0/0x186c block/blk-core.c:879 submit_bio+0x3b4/0x550 block/blk-core.c:921 submit_bio_wait+0x104/0x208 block/bio.c:1388 blkdev_issue_flush+0xb4/0x100 block/blk-flush.c:473 ext4_init_inode_table+0x420/0x780 fs/ext4/ialloc.c:1603 ext4_run_li_request fs/ext4/super.c:3729 [inline] ext4_lazyinit_thread+0x704/0x1744 fs/ext4/super.c:3824 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 IN-SOFTIRQ-W at: lock_acquire+0x14c/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 mq_flush_data_end_io+0x270/0x480 block/blk-flush.c:355 __blk_mq_end_request+0x37c/0x57c block/blk-mq.c:1150 blk_mq_end_request+0x68/0x88 block/blk-mq.c:1162 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:1265 [inline] nvme_handle_cqe drivers/nvme/host/pci.c:1329 [inline] nvme_poll_cq+0x65c/0x1018 drivers/nvme/host/pci.c:1356 nvme_irq+0x90/0x240 drivers/nvme/host/pci.c:1370 __handle_irq_event_percpu+0x224/0x8e4 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0x9c/0x1d0 kernel/irq/handle.c:257 handle_fasteoi_irq+0x328/0x8d8 kernel/irq/chip.c:764 generic_handle_irq_desc include/linux/irqdesc.h:173 [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:874 [inline] __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:925 [inline] gic_handle_irq+0x6c/0x190 drivers/irqchip/irq-gic-v3.c:969 do_interrupt_handler+0xe0/0x138 arch/arm64/kernel/entry-common.c:159 __el1_irq arch/arm64/kernel/entry-common.c:519 [inline] el1_interrupt+0x3c/0x60 arch/arm64/kernel/entry-common.c:532 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:537 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_object_active_state+0x16c/0x350 lib/debugobjects.c:1055 debug_rcu_head_unqueue kernel/rcu/rcu.h:245 [inline] rcu_do_batch kernel/rcu/tree.c:2597 [inline] rcu_core+0x7ec/0x17d0 kernel/rcu/tree.c:2861 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2878 handle_softirqs+0x328/0xc88 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 do_softirq+0x90/0xf8 kernel/softirq.c:523 __local_bh_enable_ip+0x240/0x35c kernel/softirq.c:450 local_bh_enable+0x28/0x34 include/linux/bottom_half.h:33 rcu_read_unlock_bh include/linux/rcupdate.h:936 [inline] __dev_queue_xmit+0x17ac/0x32a8 net/core/dev.c:4790 dev_queue_xmit include/linux/netdevice.h:3365 [inline] neigh_hh_output include/net/neighbour.h:531 [inline] neigh_output include/net/neighbour.h:545 [inline] ip6_finish_output2+0x1150/0x1a78 net/ipv6/ip6_output.c:136 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x418/0x7b4 net/ipv6/ip6_output.c:220 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip6_output+0x2c8/0x640 net/ipv6/ip6_output.c:247 dst_output include/net/dst.h:464 [inline] NF_HOOK+0x15c/0x430 include/linux/netfilter.h:318 mld_sendpack+0x7fc/0x100c net/ipv6/mcast.c:1855 mld_send_initial_cr+0x34c/0x534 net/ipv6/mcast.c:2271 mld_dad_work+0x40/0x418 net/ipv6/mcast.c:2294 process_one_work+0x7e8/0x155c kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3427 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 INITIAL USE at: lock_acquire+0x14c/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+0x1614/0x2168 block/blk-mq.c:3218 __submit_bio+0x1d8/0x4d8 block/blk-core.c:637 __submit_bio_noacct_mq block/blk-core.c:724 [inline] submit_bio_noacct_nocheck+0x29c/0x9a4 block/blk-core.c:755 submit_bio_noacct+0xde0/0x186c block/blk-core.c:879 submit_bio+0x3b4/0x550 block/blk-core.c:921 submit_bio_wait+0x104/0x208 block/bio.c:1388 blkdev_issue_flush+0xb4/0x100 block/blk-flush.c:473 ext4_init_inode_table+0x420/0x780 fs/ext4/ialloc.c:1603 ext4_run_li_request fs/ext4/super.c:3729 [inline] ext4_lazyinit_thread+0x704/0x1744 fs/ext4/super.c:3824 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 } ... key at: [] blk_alloc_flush_queue.__key+0x0/0x20 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (&p->sequence){+.-.}-{0:0} { HARDIRQ-ON-W at: lock_acquire+0x14c/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+0x1b4/0x818 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x51c/0x76c kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2404 handle_softirqs+0x328/0xc88 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:520 [inline] el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:532 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:537 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 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __uart_port_unlock_irqrestore include/linux/serial_core.h:616 [inline] pl011_console_device_unlock+0x90/0xc8 drivers/tty/serial/amba-pl011.c:2603 nbcon_emit_one kernel/printk/nbcon.c:1142 [inline] nbcon_kthread_func+0x58c/0x6d0 kernel/printk/nbcon.c:1229 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 IN-SOFTIRQ-W at: lock_acquire+0x14c/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+0x1b4/0x818 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x51c/0x76c kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2404 handle_softirqs+0x328/0xc88 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:520 [inline] el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:532 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:537 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 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __uart_port_unlock_irqrestore include/linux/serial_core.h:616 [inline] pl011_console_device_unlock+0x90/0xc8 drivers/tty/serial/amba-pl011.c:2603 nbcon_emit_one kernel/printk/nbcon.c:1142 [inline] nbcon_kthread_func+0x58c/0x6d0 kernel/printk/nbcon.c:1229 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 INITIAL USE at: lock_acquire+0x14c/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+0x1b4/0x818 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x51c/0x76c kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0x11c/0x194 kernel/time/timer.c:2404 handle_softirqs+0x328/0xc88 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:520 [inline] el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:532 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:537 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 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __uart_port_unlock_irqrestore include/linux/serial_core.h:616 [inline] pl011_console_device_unlock+0x90/0xc8 drivers/tty/serial/amba-pl011.c:2603 nbcon_emit_one kernel/printk/nbcon.c:1142 [inline] nbcon_kthread_func+0x58c/0x6d0 kernel/printk/nbcon.c:1229 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 INITIAL READ USE at: lock_acquire+0x14c/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:2257 [inline] wb_do_writeback fs/fs-writeback.c:2355 [inline] wb_workfn+0xa30/0xdc0 fs/fs-writeback.c:2382 process_one_work+0x7e8/0x155c kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3427 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 } ... key at: [] 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+0x380/0x75c mm/page-writeback.c:3003 folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1668 folio_end_writeback+0xd8/0x248 mm/filemap.c:1694 iomap_finish_folio_write+0x1c0/0x2a4 fs/iomap/buffered-io.c:1582 fuse_writepage_finish fs/fuse/file.c:1837 [inline] fuse_writepage_end+0x1c4/0x3b4 fs/fuse/file.c:1936 fuse_request_end+0x8b0/0xc10 fs/fuse/dev.c:507 fuse_dev_end_requests fs/fuse/dev.c:2414 [inline] fuse_abort_conn+0xe64/0x107c fs/fuse/dev.c:2512 fuse_dev_release+0x430/0x4c8 fs/fuse/dev.c:2555 __fput+0x340/0x75c fs/file_table.c:468 ____fput+0x20/0x58 fs/file_table.c:496 task_work_run+0x1dc/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xfc/0x178 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:103 [inline] el0_svc+0x170/0x254 arch/arm64/kernel/entry-common.c:747 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> (&xa->xa_lock#10){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x14c/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/0x75c mm/page-writeback.c:2996 folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1668 folio_end_writeback+0xd8/0x248 mm/filemap.c:1694 end_buffer_async_write+0x20c/0x350 fs/buffer.c:419 end_bio_bh_io_sync+0xb0/0x184 fs/buffer.c:2776 bio_endio+0x858/0x894 block/bio.c:1672 blk_update_request+0x474/0xba8 block/blk-mq.c:998 blk_mq_end_request+0x54/0x88 block/blk-mq.c:1160 lo_complete_rq+0x124/0x274 drivers/block/loop.c:314 blk_complete_reqs block/blk-mq.c:1235 [inline] blk_done_softirq+0x11c/0x168 block/blk-mq.c:1240 handle_softirqs+0x328/0xc88 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+0x14c/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:887 shmem_alloc_and_add_folio+0x73c/0x10b0 mm/shmem.c:1936 shmem_get_folio_gfp+0x4d4/0x159c mm/shmem.c:2533 shmem_read_folio_gfp+0x8c/0xf0 mm/shmem.c:5931 drm_gem_get_pages+0x1cc/0x7c0 drivers/gpu/drm/drm_gem.c:656 drm_gem_shmem_get_pages_locked+0x1d4/0x364 drivers/gpu/drm/drm_gem_shmem_helper.c:200 drm_gem_shmem_pin_locked+0x1f8/0x410 drivers/gpu/drm/drm_gem_shmem_helper.c:261 drm_gem_shmem_vmap_locked+0x3cc/0x658 drivers/gpu/drm/drm_gem_shmem_helper.c:365 drm_gem_shmem_object_vmap+0x28/0x38 include/drm/drm_gem_shmem_helper.h:243 drm_gem_vmap_locked drivers/gpu/drm/drm_gem.c:1279 [inline] drm_gem_vmap+0x104/0x1d8 drivers/gpu/drm/drm_gem.c:1321 drm_client_buffer_vmap+0x48/0x90 drivers/gpu/drm/drm_client.c:312 drm_fbdev_shmem_driver_fbdev_probe+0x1d8/0x70c drivers/gpu/drm/drm_fbdev_shmem.c:160 drm_fb_helper_single_fb_probe drivers/gpu/drm/drm_fb_helper.c:1650 [inline] __drm_fb_helper_initial_config_and_unlock+0xf94/0x159c drivers/gpu/drm/drm_fb_helper.c:1830 drm_fb_helper_initial_config+0x3c/0x58 drivers/gpu/drm/drm_fb_helper.c:1917 drm_fbdev_client_hotplug+0x154/0x22c drivers/gpu/drm/clients/drm_fbdev_client.c:52 drm_client_register+0x13c/0x1d4 drivers/gpu/drm/drm_client.c:141 drm_fbdev_client_setup+0x194/0x3d0 drivers/gpu/drm/clients/drm_fbdev_client.c:159 drm_client_setup+0x114/0x228 drivers/gpu/drm/clients/drm_client_setup.c:46 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:201 [inline] vkms_init+0x338/0x3f0 drivers/gpu/drm/vkms/vkms_drv.c:221 do_one_initcall+0x250/0x990 init/main.c:1283 do_initcall_level+0x128/0x1c4 init/main.c:1345 do_initcalls+0x70/0xd0 init/main.c:1361 do_basic_setup+0x78/0x8c init/main.c:1380 kernel_init_freeable+0x268/0x39c init/main.c:1593 kernel_init+0x24/0x1dc init/main.c:1483 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 } ... key at: [] 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/0x75c mm/page-writeback.c:2996 folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1668 folio_end_writeback+0xd8/0x248 mm/filemap.c:1694 f2fs_write_end_io+0x6b8/0xa70 fs/f2fs/data.c:362 bio_endio+0x858/0x894 block/bio.c:1672 blk_update_request+0x474/0xba8 block/blk-mq.c:998 blk_mq_end_request+0x54/0x88 block/blk-mq.c:1160 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:1150 blk_mq_end_request+0x68/0x88 block/blk-mq.c:1162 lo_complete_rq+0x124/0x274 drivers/block/loop.c:314 blk_complete_reqs block/blk-mq.c:1235 [inline] blk_done_softirq+0x11c/0x168 block/blk-mq.c:1240 handle_softirqs+0x328/0xc88 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 stack backtrace: CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025 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+0x14c/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/0x75c mm/page-writeback.c:2996 folio_end_writeback_no_dropbehind+0xd0/0x204 mm/filemap.c:1668 folio_end_writeback+0xd8/0x248 mm/filemap.c:1694 f2fs_write_end_io+0x6b8/0xa70 fs/f2fs/data.c:362 bio_endio+0x858/0x894 block/bio.c:1672 blk_update_request+0x474/0xba8 block/blk-mq.c:998 blk_mq_end_request+0x54/0x88 block/blk-mq.c:1160 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:1150 blk_mq_end_request+0x68/0x88 block/blk-mq.c:1162 lo_complete_rq+0x124/0x274 drivers/block/loop.c:314 blk_complete_reqs block/blk-mq.c:1235 [inline] blk_done_softirq+0x11c/0x168 block/blk-mq.c:1240 handle_softirqs+0x328/0xc88 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