===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected syzkaller #0 Not tainted ----------------------------------------------------- kworker/1:8/6678 [HC0[0]:SC1[1]:HE0:SE0] is trying to acquire: ffff0000f5518b40 (&xa->xa_lock#10){..-.}-{3:3}, at: __folio_end_writeback+0x10c/0x6f8 mm/page-writeback.c:2990 and this task is already holding: ffff0000cbea8218 (&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+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 preempt_schedule_common+0xe0/0x194 kernel/sched/core.c:7047 preempt_schedule+0x60/0x80 kernel/sched/core.c:7071 rcu_read_unlock_sched include/linux/rcupdate.h:981 [inline] pfn_valid+0x1f8/0x200 include/linux/mmzone.h:-1 lowmem_page_address include/linux/mm.h:2512 [inline] folio_address include/linux/mm.h:2523 [inline] slab_address mm/slab.h:163 [inline] allocate_slab+0x22c/0x424 mm/slub.c:3273 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0x9b0/0x127c mm/slub.c:4656 __slab_alloc+0x80/0x12c mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x408/0x698 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] kobject_uevent_env+0x258/0x9c8 lib/kobject_uevent.c:540 kobject_synth_uevent+0x82c/0xa74 lib/kobject_uevent.c:207 uevent_store+0x54/0x84 drivers/base/core.c:2781 drv_attr_store+0x80/0xa4 drivers/base/bus.c:125 sysfs_kf_write+0x1a8/0x23c fs/sysfs/file.c:142 kernfs_fop_write_iter+0x33c/0x4d0 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x540/0xa3c fs/read_write.c:686 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 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_enable arch/arm64/include/asm/irqflags.h:26 [inline] arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:48 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1e0/0x474 kernel/sched/idle.c:332 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:430 secondary_start_kernel+0x1bc/0x1e4 arch/arm64/kernel/smp.c:271 __secondary_switched+0xc0/0xc4 arch/arm64/kernel/head.S:401 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 *** 4 locks held by kworker/1:8/6678: #0: ffff0000d550c548 ((wq_completion)mld){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231 #1: ffff8000a6057be0 ((work_completion)(&(&idev->mc_dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231 #2: ffff0000d14b8538 (&idev->mc_lock){+.+.}-{4:4}, at: mld_dad_work+0x38/0x418 net/ipv6/mcast.c:2293 #3: ffff0000cbea8218 (&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+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 preempt_schedule_common+0xe0/0x194 kernel/sched/core.c:7047 preempt_schedule+0x60/0x80 kernel/sched/core.c:7071 rcu_read_unlock_sched include/linux/rcupdate.h:981 [inline] pfn_valid+0x1f8/0x200 include/linux/mmzone.h:-1 lowmem_page_address include/linux/mm.h:2512 [inline] folio_address include/linux/mm.h:2523 [inline] slab_address mm/slab.h:163 [inline] allocate_slab+0x22c/0x424 mm/slub.c:3273 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0x9b0/0x127c mm/slub.c:4656 __slab_alloc+0x80/0x12c mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x408/0x698 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] kobject_uevent_env+0x258/0x9c8 lib/kobject_uevent.c:540 kobject_synth_uevent+0x82c/0xa74 lib/kobject_uevent.c:207 uevent_store+0x54/0x84 drivers/base/core.c:2781 drv_attr_store+0x80/0xa4 drivers/base/bus.c:125 sysfs_kf_write+0x1a8/0x23c fs/sysfs/file.c:142 kernfs_fop_write_iter+0x33c/0x4d0 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x540/0xa3c fs/read_write.c:686 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 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 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] 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: [] 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+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_enable arch/arm64/include/asm/irqflags.h:26 [inline] arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:48 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1e0/0x474 kernel/sched/idle.c:332 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:430 secondary_start_kernel+0x1bc/0x1e4 arch/arm64/kernel/smp.c:271 __secondary_switched+0xc0/0xc4 arch/arm64/kernel/head.S:401 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_enable arch/arm64/include/asm/irqflags.h:26 [inline] arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:48 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1e0/0x474 kernel/sched/idle.c:332 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:430 secondary_start_kernel+0x1bc/0x1e4 arch/arm64/kernel/smp.c:271 __secondary_switched+0xc0/0xc4 arch/arm64/kernel/head.S:401 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_enable arch/arm64/include/asm/irqflags.h:26 [inline] arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:48 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x1e0/0x474 kernel/sched/idle.c:332 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:430 secondary_start_kernel+0x1bc/0x1e4 arch/arm64/kernel/smp.c:271 __secondary_switched+0xc0/0xc4 arch/arm64/kernel/head.S:401 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: [] 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_umount_begin+0xa4/0x130 fs/fuse/inode.c:624 do_umount fs/namespace.c:1907 [inline] path_umount+0x5dc/0x980 fs/namespace.c:2038 ksys_umount fs/namespace.c:2061 [inline] __do_sys_umount fs/namespace.c:2066 [inline] __se_sys_umount fs/namespace.c:2064 [inline] __arm64_sys_umount+0x128/0x174 fs/namespace.c:2064 __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 -> (&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 ext4_finish_bio+0x570/0x8a4 fs/ext4/page-io.c:144 ext4_end_bio+0x360/0x610 fs/ext4/page-io.c:-1 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 __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] raise_softirq+0xa8/0xe0 kernel/softirq.c:783 blk_mq_raise_softirq block/blk-mq.c:1306 [inline] blk_mq_complete_request_remote+0x618/0x88c block/blk-mq.c:1330 blk_mq_complete_request+0x24/0xa8 block/blk-mq.c:1346 lo_rw_aio_do_completion+0x138/0x19c drivers/block/loop.c:329 lo_rw_aio_complete drivers/block/loop.c:337 [inline] lo_rw_aio+0x94c/0xa78 drivers/block/loop.c:410 do_req_filebacked drivers/block/loop.c:-1 [inline] loop_handle_cmd drivers/block/loop.c:1926 [inline] loop_process_work+0x808/0x1058 drivers/block/loop.c:1961 loop_workfn+0x50/0x64 drivers/block/loop.c:1985 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 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: [] 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 __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 __alloc_skb+0x1bc/0x3b0 net/core/skbuff.c:674 alloc_skb include/linux/skbuff.h:1383 [inline] mld_newpack+0x130/0xa28 net/ipv6/mcast.c:1775 add_grhead+0x6c/0x25c net/ipv6/mcast.c:1886 add_grec+0x1120/0x13c8 net/ipv6/mcast.c:2025 mld_send_initial_cr+0x27c/0x534 net/ipv6/mcast.c:2268 mld_dad_work+0x40/0x418 net/ipv6/mcast.c:2294 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 stack backtrace: CPU: 1 UID: 0 PID: 6678 Comm: kworker/1:8 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 Workqueue: mld mld_dad_work 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 __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 __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 __alloc_skb+0x1bc/0x3b0 net/core/skbuff.c:674 alloc_skb include/linux/skbuff.h:1383 [inline] mld_newpack+0x130/0xa28 net/ipv6/mcast.c:1775 add_grhead+0x6c/0x25c net/ipv6/mcast.c:1886 add_grec+0x1120/0x13c8 net/ipv6/mcast.c:2025 mld_send_initial_cr+0x27c/0x534 net/ipv6/mcast.c:2268 mld_dad_work+0x40/0x418 net/ipv6/mcast.c:2294 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