===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected syzkaller #0 Not tainted ----------------------------------------------------- syz-executor/7062 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff80008d2e4630 (&p->sequence){+.-.}-{0:0}, at: __fprop_add_percpu_max+0xf8/0x14c lib/flex_proportions.c:186 and this task is already holding: ffff00001cfb9740 (&xa->xa_lock#8){-...}-{3:3}, at: __folio_end_writeback+0x20c/0x85c mm/page-writeback.c:2996 which would create a new lock dependency: (&xa->xa_lock#8){-...}-{3:3} -> (&p->sequence){+.-.}-{0:0} but this new dependency connects a HARDIRQ-irq-safe lock: (&xa->xa_lock#8){-...}-{3:3} ... which became HARDIRQ-irq-safe at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x58/0x80 kernel/locking/spinlock.c:162 __folio_end_writeback+0x20c/0x85c mm/page-writeback.c:2996 folio_end_writeback_no_dropbehind+0x74/0x1dc mm/filemap.c:1668 folio_end_writeback+0xa8/0x1dc mm/filemap.c:1694 end_buffer_async_write+0x194/0x268 fs/buffer.c:419 end_bio_bh_io_sync+0xb8/0x128 fs/buffer.c:2776 bio_endio+0x56c/0x748 block/bio.c:1673 blk_update_request+0x4a0/0x11a4 block/blk-mq.c:998 blk_mq_end_request+0x58/0x338 block/blk-mq.c:1160 virtblk_request_done+0x150/0x23c drivers/block/virtio_blk.c:347 blk_mq_complete_request block/blk-mq.c:1338 [inline] blk_mq_complete_request+0x78/0xa4 block/blk-mq.c:1335 virtblk_done+0x130/0x2d4 drivers/block/virtio_blk.c:366 vring_interrupt drivers/virtio/virtio_ring.c:2718 [inline] vring_interrupt+0x190/0x310 drivers/virtio/virtio_ring.c:2693 __handle_irq_event_percpu+0x19c/0x7f0 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0xb0/0x1d8 kernel/irq/handle.c:257 handle_fasteoi_irq+0x2fc/0x97c kernel/irq/chip.c:764 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq_desc+0xd0/0x110 kernel/irq/irqdesc.c:669 generic_handle_domain_irq+0x1c/0x28 kernel/irq/irqdesc.c:725 gic_handle_irq+0x54/0x184 drivers/irqchip/irq-gic.c:370 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_interrupt_handler+0x12c/0x150 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 kernel/sched/core.c:5073 [inline] finish_task_switch.isra.0+0x1ac/0x854 kernel/sched/core.c:5191 context_switch kernel/sched/core.c:5328 [inline] __schedule+0xd5c/0x3180 kernel/sched/core.c:6929 preempt_schedule_common kernel/sched/core.c:7113 [inline] preempt_schedule+0xf4/0x254 kernel/sched/core.c:7137 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x94/0xac kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock kernel/sched/wait.c:127 [inline] __wake_up_sync_key+0x50/0x68 kernel/sched/wait.c:192 sock_def_readable+0x120/0x494 net/core/sock.c:3551 __netlink_sendskb net/netlink/af_netlink.c:1265 [inline] netlink_sendskb net/netlink/af_netlink.c:1271 [inline] netlink_unicast+0x5a0/0x700 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x640/0xa50 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0xc8/0x168 net/socket.c:742 ____sys_sendmsg+0x500/0x764 net/socket.c:2630 ___sys_sendmsg+0x11c/0x19c net/socket.c:2684 __sys_sendmsg+0x114/0x19c net/socket.c:2716 __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __arm64_sys_sendmsg+0x70/0xa0 net/socket.c:2719 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 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 kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline] do_write_seqcount_begin include/linux/seqlock.h:503 [inline] fprop_new_period+0x9c/0x6e0 lib/flex_proportions.c:74 writeout_period+0x84/0x128 mm/page-writeback.c:615 call_timer_fn+0x1b0/0x7a8 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers+0x778/0x9a8 kernel/time/timer.c:2372 __run_timer_base kernel/time/timer.c:2384 [inline] __run_timer_base kernel/time/timer.c:2376 [inline] run_timer_base+0x110/0x180 kernel/time/timer.c:2393 run_timer_softirq+0x24/0x44 kernel/time/timer.c:2404 handle_softirqs+0x2d8/0xdb4 kernel/softirq.c:622 __do_softirq+0x14/0x20 kernel/softirq.c:656 ____do_softirq+0x10/0x1c arch/arm64/kernel/irq.c:68 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_softirq_own_stack+0x1c/0x2c arch/arm64/kernel/irq.c:73 invoke_softirq kernel/softirq.c:503 [inline] __irq_exit_rcu+0x3f8/0x554 kernel/softirq.c:723 irq_exit_rcu+0x14/0x80 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 unwind_find_stack.constprop.0+0x0/0x80 stack_trace_save+0x9c/0xd8 kernel/stacktrace.c:122 kasan_save_stack+0x3c/0x64 mm/kasan/common.c:56 kasan_save_track+0x20/0x3c mm/kasan/common.c:77 kasan_save_alloc_info+0x40/0x54 mm/kasan/generic.c:573 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x8c/0x90 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4946 [inline] slab_alloc_node mm/slub.c:5245 [inline] kmem_cache_alloc_noprof+0x24c/0x6e4 mm/slub.c:5252 alloc_empty_file+0x5c/0x16c fs/file_table.c:237 path_openat+0xd0/0x24b0 fs/namei.c:4120 do_filp_open+0x184/0x360 fs/namei.c:4161 do_sys_openat2+0xe0/0x160 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __arm64_sys_openat+0x12c/0x1bc fs/open.c:1463 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->sequence); local_irq_disable(); lock(&xa->xa_lock#8); lock(&p->sequence); lock(&xa->xa_lock#8); *** DEADLOCK *** 3 locks held by syz-executor/7062: #0: ffff000017a82420 (sb_writers#14){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #0: ffff000017a82420 (sb_writers#14){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1916 [inline] #0: ffff000017a82420 (sb_writers#14){.+.+}-{0:0}, at: sb_start_write include/linux/fs.h:2052 [inline] #0: ffff000017a82420 (sb_writers#14){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3111 [inline] #0: ffff000017a82420 (sb_writers#14){.+.+}-{0:0}, at: vfs_write+0x670/0xb88 fs/read_write.c:682 #1: ffff00001cfb9b38 (&fi->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #1: ffff00001cfb9b38 (&fi->lock){+.+.}-{3:3}, at: fuse_writepage_end+0xc4/0x278 fs/fuse/file.c:1934 #2: ffff00001cfb9740 (&xa->xa_lock#8){-...}-{3:3}, at: __folio_end_writeback+0x20c/0x85c mm/page-writeback.c:2996 the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&xa->xa_lock#8){-...}-{3:3} { IN-HARDIRQ-W at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x58/0x80 kernel/locking/spinlock.c:162 __folio_end_writeback+0x20c/0x85c mm/page-writeback.c:2996 folio_end_writeback_no_dropbehind+0x74/0x1dc mm/filemap.c:1668 folio_end_writeback+0xa8/0x1dc mm/filemap.c:1694 end_buffer_async_write+0x194/0x268 fs/buffer.c:419 end_bio_bh_io_sync+0xb8/0x128 fs/buffer.c:2776 bio_endio+0x56c/0x748 block/bio.c:1673 blk_update_request+0x4a0/0x11a4 block/blk-mq.c:998 blk_mq_end_request+0x58/0x338 block/blk-mq.c:1160 virtblk_request_done+0x150/0x23c drivers/block/virtio_blk.c:347 blk_mq_complete_request block/blk-mq.c:1338 [inline] blk_mq_complete_request+0x78/0xa4 block/blk-mq.c:1335 virtblk_done+0x130/0x2d4 drivers/block/virtio_blk.c:366 vring_interrupt drivers/virtio/virtio_ring.c:2718 [inline] vring_interrupt+0x190/0x310 drivers/virtio/virtio_ring.c:2693 __handle_irq_event_percpu+0x19c/0x7f0 kernel/irq/handle.c:203 handle_irq_event_percpu kernel/irq/handle.c:240 [inline] handle_irq_event+0xb0/0x1d8 kernel/irq/handle.c:257 handle_fasteoi_irq+0x2fc/0x97c kernel/irq/chip.c:764 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq_desc+0xd0/0x110 kernel/irq/irqdesc.c:669 generic_handle_domain_irq+0x1c/0x28 kernel/irq/irqdesc.c:725 gic_handle_irq+0x54/0x184 drivers/irqchip/irq-gic.c:370 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_interrupt_handler+0x12c/0x150 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 kernel/sched/core.c:5073 [inline] finish_task_switch.isra.0+0x1ac/0x854 kernel/sched/core.c:5191 context_switch kernel/sched/core.c:5328 [inline] __schedule+0xd5c/0x3180 kernel/sched/core.c:6929 preempt_schedule_common kernel/sched/core.c:7113 [inline] preempt_schedule+0xf4/0x254 kernel/sched/core.c:7137 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x94/0xac kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock kernel/sched/wait.c:127 [inline] __wake_up_sync_key+0x50/0x68 kernel/sched/wait.c:192 sock_def_readable+0x120/0x494 net/core/sock.c:3551 __netlink_sendskb net/netlink/af_netlink.c:1265 [inline] netlink_sendskb net/netlink/af_netlink.c:1271 [inline] netlink_unicast+0x5a0/0x700 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x640/0xa50 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0xc8/0x168 net/socket.c:742 ____sys_sendmsg+0x500/0x764 net/socket.c:2630 ___sys_sendmsg+0x11c/0x19c net/socket.c:2684 __sys_sendmsg+0x114/0x19c net/socket.c:2716 __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __arm64_sys_sendmsg+0x70/0xa0 net/socket.c:2719 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x54/0x74 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] shmem_add_to_page_cache+0x408/0x77c mm/shmem.c:887 shmem_alloc_and_add_folio+0x350/0xd74 mm/shmem.c:1936 shmem_get_folio_gfp+0x430/0x1140 mm/shmem.c:2533 shmem_read_folio_gfp+0xc8/0x128 mm/shmem.c:5931 drm_gem_get_pages+0x180/0x5f8 drivers/gpu/drm/drm_gem.c:656 drm_gem_shmem_get_pages_locked+0x1b8/0x310 drivers/gpu/drm/drm_gem_shmem_helper.c:200 drm_gem_shmem_pin_locked+0x1dc/0x3d0 drivers/gpu/drm/drm_gem_shmem_helper.c:261 drm_gem_shmem_vmap_locked+0x38c/0x610 drivers/gpu/drm/drm_gem_shmem_helper.c:365 drm_gem_shmem_object_vmap+0x10/0x1c include/drm/drm_gem_shmem_helper.h:243 drm_gem_vmap_locked+0x98/0x140 drivers/gpu/drm/drm_gem.c:1279 drm_gem_vmap+0x4c/0xa4 drivers/gpu/drm/drm_gem.c:1321 drm_client_buffer_vmap+0x44/0xb4 drivers/gpu/drm/drm_client.c:312 drm_fbdev_shmem_driver_fbdev_probe+0x25c/0x7c0 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+0x888/0x120c drivers/gpu/drm/drm_fb_helper.c:1830 drm_fb_helper_initial_config drivers/gpu/drm/drm_fb_helper.c:1917 [inline] drm_fb_helper_initial_config+0x48/0x58 drivers/gpu/drm/drm_fb_helper.c:1909 drm_fbdev_client_hotplug+0x140/0x1fc drivers/gpu/drm/clients/drm_fbdev_client.c:52 drm_client_register+0x12c/0x1ec drivers/gpu/drm/drm_client.c:141 drm_fbdev_client_setup+0x154/0x3f4 drivers/gpu/drm/clients/drm_fbdev_client.c:159 drm_client_setup drivers/gpu/drm/clients/drm_client_setup.c:46 [inline] drm_client_setup+0x150/0x1e8 drivers/gpu/drm/clients/drm_client_setup.c:35 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:201 [inline] vkms_init+0x3c8/0x4d4 drivers/gpu/drm/vkms/vkms_drv.c:221 do_one_initcall+0x130/0x7f0 init/main.c:1283 do_initcall_level init/main.c:1345 [inline] do_initcalls init/main.c:1361 [inline] do_basic_setup init/main.c:1380 [inline] kernel_init_freeable+0x48c/0x714 init/main.c:1593 kernel_init+0x24/0x1dc init/main.c:1483 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 } ... key at: [] __key.4+0x0/0x40 the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (&p->sequence){+.-.}-{0:0} { HARDIRQ-ON-W at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline] do_write_seqcount_begin include/linux/seqlock.h:503 [inline] fprop_new_period+0x9c/0x6e0 lib/flex_proportions.c:74 writeout_period+0x84/0x128 mm/page-writeback.c:615 call_timer_fn+0x1b0/0x7a8 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers+0x778/0x9a8 kernel/time/timer.c:2372 __run_timer_base kernel/time/timer.c:2384 [inline] __run_timer_base kernel/time/timer.c:2376 [inline] run_timer_base+0x110/0x180 kernel/time/timer.c:2393 run_timer_softirq+0x24/0x44 kernel/time/timer.c:2404 handle_softirqs+0x2d8/0xdb4 kernel/softirq.c:622 __do_softirq+0x14/0x20 kernel/softirq.c:656 ____do_softirq+0x10/0x1c arch/arm64/kernel/irq.c:68 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_softirq_own_stack+0x1c/0x2c arch/arm64/kernel/irq.c:73 invoke_softirq kernel/softirq.c:503 [inline] __irq_exit_rcu+0x3f8/0x554 kernel/softirq.c:723 irq_exit_rcu+0x14/0x80 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 unwind_find_stack.constprop.0+0x0/0x80 stack_trace_save+0x9c/0xd8 kernel/stacktrace.c:122 kasan_save_stack+0x3c/0x64 mm/kasan/common.c:56 kasan_save_track+0x20/0x3c mm/kasan/common.c:77 kasan_save_alloc_info+0x40/0x54 mm/kasan/generic.c:573 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x8c/0x90 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4946 [inline] slab_alloc_node mm/slub.c:5245 [inline] kmem_cache_alloc_noprof+0x24c/0x6e4 mm/slub.c:5252 alloc_empty_file+0x5c/0x16c fs/file_table.c:237 path_openat+0xd0/0x24b0 fs/namei.c:4120 do_filp_open+0x184/0x360 fs/namei.c:4161 do_sys_openat2+0xe0/0x160 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __arm64_sys_openat+0x12c/0x1bc fs/open.c:1463 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 IN-SOFTIRQ-W at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline] do_write_seqcount_begin include/linux/seqlock.h:503 [inline] fprop_new_period+0x9c/0x6e0 lib/flex_proportions.c:74 writeout_period+0x84/0x128 mm/page-writeback.c:615 call_timer_fn+0x1b0/0x7a8 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers+0x778/0x9a8 kernel/time/timer.c:2372 __run_timer_base kernel/time/timer.c:2384 [inline] __run_timer_base kernel/time/timer.c:2376 [inline] run_timer_base+0x110/0x180 kernel/time/timer.c:2393 run_timer_softirq+0x24/0x44 kernel/time/timer.c:2404 handle_softirqs+0x2d8/0xdb4 kernel/softirq.c:622 __do_softirq+0x14/0x20 kernel/softirq.c:656 ____do_softirq+0x10/0x1c arch/arm64/kernel/irq.c:68 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_softirq_own_stack+0x1c/0x2c arch/arm64/kernel/irq.c:73 invoke_softirq kernel/softirq.c:503 [inline] __irq_exit_rcu+0x3f8/0x554 kernel/softirq.c:723 irq_exit_rcu+0x14/0x80 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 unwind_find_stack.constprop.0+0x0/0x80 stack_trace_save+0x9c/0xd8 kernel/stacktrace.c:122 kasan_save_stack+0x3c/0x64 mm/kasan/common.c:56 kasan_save_track+0x20/0x3c mm/kasan/common.c:77 kasan_save_alloc_info+0x40/0x54 mm/kasan/generic.c:573 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x8c/0x90 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4946 [inline] slab_alloc_node mm/slub.c:5245 [inline] kmem_cache_alloc_noprof+0x24c/0x6e4 mm/slub.c:5252 alloc_empty_file+0x5c/0x16c fs/file_table.c:237 path_openat+0xd0/0x24b0 fs/namei.c:4120 do_filp_open+0x184/0x360 fs/namei.c:4161 do_sys_openat2+0xe0/0x160 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __arm64_sys_openat+0x12c/0x1bc fs/open.c:1463 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 INITIAL USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline] do_write_seqcount_begin include/linux/seqlock.h:503 [inline] fprop_new_period+0x9c/0x6e0 lib/flex_proportions.c:74 writeout_period+0x84/0x128 mm/page-writeback.c:615 call_timer_fn+0x1b0/0x7a8 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers+0x778/0x9a8 kernel/time/timer.c:2372 __run_timer_base kernel/time/timer.c:2384 [inline] __run_timer_base kernel/time/timer.c:2376 [inline] run_timer_base+0x110/0x180 kernel/time/timer.c:2393 run_timer_softirq+0x24/0x44 kernel/time/timer.c:2404 handle_softirqs+0x2d8/0xdb4 kernel/softirq.c:622 __do_softirq+0x14/0x20 kernel/softirq.c:656 ____do_softirq+0x10/0x1c arch/arm64/kernel/irq.c:68 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:891 do_softirq_own_stack+0x1c/0x2c arch/arm64/kernel/irq.c:73 invoke_softirq kernel/softirq.c:503 [inline] __irq_exit_rcu+0x3f8/0x554 kernel/softirq.c:723 irq_exit_rcu+0x14/0x80 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 unwind_find_stack.constprop.0+0x0/0x80 stack_trace_save+0x9c/0xd8 kernel/stacktrace.c:122 kasan_save_stack+0x3c/0x64 mm/kasan/common.c:56 kasan_save_track+0x20/0x3c mm/kasan/common.c:77 kasan_save_alloc_info+0x40/0x54 mm/kasan/generic.c:573 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x8c/0x90 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4946 [inline] slab_alloc_node mm/slub.c:5245 [inline] kmem_cache_alloc_noprof+0x24c/0x6e4 mm/slub.c:5252 alloc_empty_file+0x5c/0x16c fs/file_table.c:237 path_openat+0xd0/0x24b0 fs/namei.c:4120 do_filp_open+0x184/0x360 fs/namei.c:4161 do_sys_openat2+0xe0/0x160 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __arm64_sys_openat+0x12c/0x1bc fs/open.c:1463 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 INITIAL READ USE at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline] fprop_fraction_percpu+0x1f4/0x280 lib/flex_proportions.c:155 __wb_calc_thresh+0xf4/0x3c4 mm/page-writeback.c:913 wb_bg_dirty_limits mm/page-writeback.c:2130 [inline] domain_over_bg_thresh+0xa8/0x218 mm/page-writeback.c:2144 wb_over_bg_thresh+0xd4/0x13c 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+0x528/0xa9c fs/fs-writeback.c:2382 process_one_work+0x7cc/0x18d4 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x734/0xb84 kernel/workqueue.c:3427 kthread+0x348/0x5fc kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 } ... key at: [] __key.2+0x0/0x40 ... acquired at: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline] fprop_fraction_percpu+0xb4/0x280 lib/flex_proportions.c:155 __fprop_add_percpu_max+0xf8/0x14c lib/flex_proportions.c:186 wb_domain_writeout_add mm/page-writeback.c:562 [inline] __wb_writeout_add mm/page-writeback.c:586 [inline] __folio_end_writeback+0x3fc/0x85c mm/page-writeback.c:3003 folio_end_writeback_no_dropbehind+0x74/0x1dc mm/filemap.c:1668 folio_end_writeback+0xa8/0x1dc mm/filemap.c:1694 iomap_finish_folio_write+0x154/0x250 fs/iomap/buffered-io.c:1582 fuse_writepage_finish+0xc0/0x154 fs/fuse/file.c:1837 fuse_writepage_end+0xfc/0x278 fs/fuse/file.c:1936 fuse_request_end+0x4b8/0x7f0 fs/fuse/dev.c:507 fuse_dev_end_requests+0x11c/0x1d8 fs/fuse/dev.c:2414 fuse_abort_conn+0x788/0xaec fs/fuse/dev.c:2512 fuse_conn_abort_write+0xe0/0x140 fs/fuse/control.c:42 vfs_write+0x1d8/0xb88 fs/read_write.c:684 ksys_write+0xec/0x1d8 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+0x6c/0x9c fs/read_write.c:746 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 stack backtrace: CPU: 0 UID: 0 PID: 7062 Comm: syz-executor Not tainted syzkaller #0 PREEMPT Hardware name: linux,dummy-virt (DT) Call trace: show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xa4/0xf4 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+0x78c/0xadc kernel/locking/lockdep.c:2857 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+0x1650/0x2380 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline] fprop_fraction_percpu+0xb4/0x280 lib/flex_proportions.c:155 __fprop_add_percpu_max+0xf8/0x14c lib/flex_proportions.c:186 wb_domain_writeout_add mm/page-writeback.c:562 [inline] __wb_writeout_add mm/page-writeback.c:586 [inline] __folio_end_writeback+0x3fc/0x85c mm/page-writeback.c:3003 folio_end_writeback_no_dropbehind+0x74/0x1dc mm/filemap.c:1668 folio_end_writeback+0xa8/0x1dc mm/filemap.c:1694 iomap_finish_folio_write+0x154/0x250 fs/iomap/buffered-io.c:1582 fuse_writepage_finish+0xc0/0x154 fs/fuse/file.c:1837 fuse_writepage_end+0xfc/0x278 fs/fuse/file.c:1936 fuse_request_end+0x4b8/0x7f0 fs/fuse/dev.c:507 fuse_dev_end_requests+0x11c/0x1d8 fs/fuse/dev.c:2414 fuse_abort_conn+0x788/0xaec fs/fuse/dev.c:2512 fuse_conn_abort_write+0xe0/0x140 fs/fuse/control.c:42 vfs_write+0x1d8/0xb88 fs/read_write.c:684 ksys_write+0xec/0x1d8 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+0x6c/0x9c fs/read_write.c:746 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x288 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596