INFO: task udevd:5251 blocked for more than 143 seconds. Not tainted 6.12.0-rc6-syzkaller-00153-g237d4e0f4113 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24272 pid:5251 tgid:5251 ppid:2864 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x1042/0x34b0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6839 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 device_lock include/linux/device.h:1014 [inline] uevent_show+0x188/0x3b0 drivers/base/core.c:2736 dev_attr_show+0x53/0xe0 drivers/base/core.c:2430 sysfs_kf_seq_show+0x23e/0x410 fs/sysfs/file.c:59 seq_read_iter+0x4f4/0x12b0 fs/seq_file.c:230 kernfs_fop_read_iter+0x414/0x580 fs/kernfs/file.c:279 new_sync_read fs/read_write.c:488 [inline] vfs_read+0x87f/0xbe0 fs/read_write.c:569 ksys_read+0x12f/0x260 fs/read_write.c:712 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcc984edb6a RSP: 002b:00007fff9c72b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00005629e4230940 RCX: 00007fcc984edb6a RDX: 0000000000001000 RSI: 00005629e4240620 RDI: 0000000000000008 RBP: 00005629e4230940 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007fff9c72b508 R15: 000000000000000a Showing all locks held in the system: 3 locks held by kworker/0:0/8: 1 lock held by khungtaskd/30: #0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 2 locks held by getty/2924: #0: ffff88810834f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 4 locks held by udevd/5204: #0: ffff88812e8e9d58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff888113d6c888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff8881126ff008 (kn->active){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888131a15190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff888131a15190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2736 4 locks held by udevd/5214: #0: ffff8881073ddb08 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff888113d6e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88810eb0e1e8 (kn->active){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88811ad6b190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88811ad6b190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2736 4 locks held by udevd/5251: #0: ffff888120b788b8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff888118ddb088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88810f7bd0f8 ( kn->active){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff8881190ff190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8881190ff190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2736 4 locks held by kworker/1:6/5280: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9000276fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810ab2c190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88810ab2c190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88811ad6b190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88811ad6b190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 5 locks held by kworker/0:4/5287: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc900027c7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810afa2190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88810afa2190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff8881190ff190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8881190ff190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff88811847b160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88811847b160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 5 locks held by kworker/0:7/7207: #0: ffff888105ef6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc900110e7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88810afba190 (&dev->mutex){....}-{3:3} , at: device_lock include/linux/device.h:1014 [inline] , at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff888131a15190 (&dev->mutex ){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] ){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff888131db0160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 1 lock held by syz.0.1010/8788: #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297 2 locks held by syz.3.1011/8791: 2 locks held by syz.3.1011/8796: #0: ffff888100ebe3f8 (sb_writers){.+.+}-{0:0}, at: ioctl_preallocate+0x1a2/0x220 fs/ioctl.c:291 #1: ffff888114190f60 (&sb->s_type->i_mutex_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff888114190f60 (&sb->s_type->i_mutex_key#4){++++}-{3:3}, at: shmem_fallocate+0x19a/0xfa0 mm/shmem.c:3392 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc6-syzkaller-00153-g237d4e0f4113 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8791 Comm: syz.3.1011 Not tainted 6.12.0-rc6-syzkaller-00153-g237d4e0f4113 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:check_wait_context kernel/locking/lockdep.c:4852 [inline] RIP: 0010:__lock_acquire+0x62d/0x3ce0 kernel/locking/lockdep.c:5152 Code: 69 c5 c8 00 00 00 48 05 c0 d1 aa 8f 48 8d b8 c4 00 00 00 48 89 f9 48 89 fe 48 c1 e9 03 83 e6 07 42 0f b6 0c 21 40 38 f1 7f 08 <84> c9 0f 85 e6 22 00 00 0f b6 88 c4 00 00 00 84 c9 74 3a 48 8d b8 RSP: 0018:ffffc900111af588 EFLAGS: 00000097 RAX: ffffffff8fac2980 RBX: ffffed1022bd3152 RCX: 0000000000000000 RDX: fffffbfff1f559bb RSI: 0000000000000004 RDI: ffffffff8fac2a44 RBP: 00000000000001b8 R08: 0000000000000000 R09: fffffbfff1f559ba R10: ffffffff8faacdd7 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000001 R14: 0000000000000004 R15: ffff888115e98000 FS: 00007f5e21a576c0(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200063c0 CR3: 0000000116f4e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __folio_batch_add_and_move+0x6a2/0xc60 mm/swap.c:237 shmem_alloc_and_add_folio mm/shmem.c:1869 [inline] shmem_get_folio_gfp.constprop.0+0xa65/0x14a0 mm/shmem.c:2332 shmem_get_folio mm/shmem.c:2438 [inline] shmem_fallocate+0x7b9/0xfa0 mm/shmem.c:3479 vfs_fallocate+0x409/0xe60 fs/open.c:333 ioctl_preallocate+0x1a2/0x220 fs/ioctl.c:291 file_ioctl fs/ioctl.c:331 [inline] do_vfs_ioctl+0x15cb/0x1990 fs/ioctl.c:886 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x118/0x220 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5e22dde719 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5e21a57038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5e22f95f80 RCX: 00007f5e22dde719 RDX: 0000000020000200 RSI: 000000004030582a RDI: 0000000000000005 RBP: 00007f5e22e5175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5e22f95f80 R15: 00007ffcaf5a4138