INFO: task kworker/u4:2:39 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack:0 pid:39 ppid:2 flags:0x00000008 Workqueue: quota_events_unbound quota_release_workfn Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5246 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6563 schedule+0xc4/0x170 kernel/sched/core.c:6639 schedule_timeout+0xc8/0x2f4 kernel/time/timer.c:2144 do_wait_for_common+0x28c/0x3ec kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x44/0x5c kernel/sched/completion.c:138 __synchronize_srcu+0x26c/0x304 kernel/rcu/srcutree.c:1243 synchronize_srcu+0x194/0x1ac kernel/rcu/srcutree.c:-1 quota_release_workfn+0x104/0x618 fs/quota/dquot.c:855 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439 kthread+0x254/0x2e0 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 INFO: task syz.0.17:4483 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:0 pid:4483 ppid:4469 flags:0x00000001 Call trace: __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555 context_switch kernel/sched/core.c:5246 [inline] __schedule+0xdb4/0x1a6c kernel/sched/core.c:6563 schedule+0xc4/0x170 kernel/sched/core.c:6639 io_schedule+0x84/0x154 kernel/sched/core.c:8799 bit_wait_io+0x1c/0xac kernel/sched/wait_bit.c:209 __wait_on_bit_lock+0xb8/0x1dc kernel/sched/wait_bit.c:90 out_of_line_wait_on_bit_lock+0x130/0x184 kernel/sched/wait_bit.c:117 wait_on_bit_lock_io include/linux/wait_bit.h:208 [inline] __lock_buffer+0x78/0xa8 fs/buffer.c:69 lock_buffer include/linux/buffer_head.h:397 [inline] ext4_quota_write+0x330/0x544 fs/ext4/super.c:7243 qtree_write_dquot+0x1e0/0x4e4 fs/quota/quota_tree.c:462 v2_write_dquot+0xf0/0x180 fs/quota/quota_v2.c:361 dquot_commit+0x12c/0x1c8 fs/quota/dquot.c:542 ext4_write_dquot+0x1b4/0x320 fs/ext4/super.c:6817 ext4_mark_dquot_dirty+0xe8/0x150 fs/ext4/super.c:6894 mark_dquot_dirty fs/quota/dquot.c:400 [inline] mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:440 __dquot_free_space+0x768/0xaa4 fs/quota/dquot.c:1967 dquot_free_space_nodirty include/linux/quotaops.h:372 [inline] ext4_xattr_inode_free_quota+0x10c/0x184 fs/ext4/xattr.c:882 ext4_xattr_set_entry+0xa2c/0x15f4 fs/ext4/xattr.c:1677 ext4_xattr_block_set+0x16ac/0x28f8 fs/ext4/xattr.c:1910 ext4_xattr_set_handle+0xc00/0x12d4 fs/ext4/xattr.c:2403 ext4_xattr_set+0x1e8/0x2b4 fs/ext4/xattr.c:2505 ext4_xattr_trusted_set+0x4c/0x64 fs/ext4/xattr_trusted.c:38 __vfs_setxattr+0x374/0x390 fs/xattr.c:182 __vfs_setxattr_noperm+0x120/0x56c fs/xattr.c:216 __vfs_setxattr_locked+0x1e8/0x214 fs/xattr.c:277 vfs_setxattr+0x158/0x2a8 fs/xattr.c:309 do_setxattr fs/xattr.c:594 [inline] setxattr+0x258/0x2d8 fs/xattr.c:617 path_setxattr+0x130/0x260 fs/xattr.c:636 __do_sys_setxattr fs/xattr.c:652 [inline] __se_sys_setxattr fs/xattr.c:648 [inline] __arm64_sys_setxattr+0xc4/0xe0 fs/xattr.c:648 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffff800015577db0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffff8000155785d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffff800015577440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349 2 locks held by kworker/u4:2/39: #0: ffff0000c4b4f138 ((wq_completion)quota_events_unbound){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1 #1: ffff80001dfe7c40 ((quota_release_work).work){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267 3 locks held by kworker/u4:3/196: 3 locks held by kworker/1:3/3902: #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1 #1: ffff800023807c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267 #2: ffff0000d9b17240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x1d8/0x2708 drivers/net/netdevsim/fib.c:1491 2 locks held by getty/4085: #0: ffff0000d6fd1098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80001fa362f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2e8/0xfa8 drivers/tty/n_tty.c:2198 6 locks held by syz.0.17/4483: #0: ffff0000d483e460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e53b5e48 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e53b5e48 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e53b5b10 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e53b5b10 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000dff1c0a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000d483e208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.1.18/4501: #0: ffff0000d9fd6460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e536a218 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e536a218 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e5369ee0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e5369ee0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000dff1c428 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000d9fd6208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.2.19/4519: #0: ffff0000ccc12460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000f108e850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000f108e850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000f108e518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000f108e518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000dff1c5e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000ccc12208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.3.20/4539: #0: ffff0000cc790460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e5170400 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e5170400 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e51700c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e51700c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000e53e6268 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000cc790208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.4.21/4571: #0: ffff0000ca638460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e5175440 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e5175440 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e5175108 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e5175108 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000dff1cb28 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000ca638208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.5.22/4599: #0: ffff0000f2aea460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e52c9810 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e52c9810 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e52c94d8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e52c94d8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000dff1cea8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000f2aea208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.6.23/4627: #0: ffff0000efa12460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e52ce850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e52ce850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e52ce518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e52ce518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000dff1d228 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000efa12208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.7.24/4657: #0: ffff0000d0694460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e5264a38 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e5264a38 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e5264700 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e5264700 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000e53e6428 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000d0694208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.8.25/4688: #0: ffff0000c33ec460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000e5266850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000e5266850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000e5266518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000e5266518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000dff1d5a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000c33ec208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 6 locks held by syz.9.26/4716: #0: ffff0000f66e4460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:402 #1: ffff0000f13a3628 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #1: ffff0000f13a3628 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x138/0x2a8 fs/xattr.c:308 #2: ffff0000f13a32f0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] #2: ffff0000f13a32f0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x138/0x12d4 fs/ext4/xattr.c:2318 #3: ffff8000156acca8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:349 #4: ffff0000e53e6968 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x1c8 fs/quota/dquot.c:535 #5: ffff0000f66e4208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x80/0x180 fs/quota/quota_v2.c:359 =============================================