INFO: task syz.0.2045:19601 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2045 state:D stack:28216 pid:19601 tgid:19595 ppid:5813 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 sync_bdevs+0x153/0x480 block/bdev.c:1305 ksys_sync+0xb2/0x150 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc4dcb9aeb9 RSP: 002b:00007fc4dadee028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fc4dce15fa0 RCX: 00007fc4dcb9aeb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fc4dce15fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc4dce16038 R14: 00007fc4dce15fa0 R15: 00007ffe02f4f588 Showing all locks held in the system: 2 locks held by kdevtmpfs/26: 1 lock held by khungtaskd/31: #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/5566: #0: ffff88814def70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 1 lock held by udevd/5814: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:962 7 locks held by kworker/0:5/5878: #0: ffff88801eab8d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90003037c98 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffff888029a79198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #2: ffff888029a79198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88807eac3198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff88807eac3198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336 #4: ffff88801e6d2160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #4: ffff88801e6d2160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1106 [inline] #4: ffff88801e6d2160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xaa/0x600 drivers/base/dd.c:1304 #5: ffffffff8fbfeda8 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #5: ffffffff8fbfeda8 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x184/0x4d0 drivers/input/input.c:2187 #6: ffffffff8e5efab8 (rcu_state.exp_mutex){+.+.}-{4:4} , at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 4 locks held by udevd/5923: #0: ffff88807afcb2f0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:182 #1: ffff88805e5b3888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff8880305b4788 (kn->active#20){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] ffff8880305b4788 (kn->active#20){.+.+}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88807eac3198 ( &dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] &dev->mutex){....}-{4:4}, at: product_show+0x26/0xa0 drivers/usb/core/sysfs.c:141 2 locks held by dhcpcd/6231: #0: ffff88805dda2a48 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805dda2a48 (&sb->s_type->i_mutex_key#12){+.+.}-{4:4}, at: __sock_release+0x86/0x260 net/socket.c:661 #1: ffffffff8e5efab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 1 lock held by syz.0.2045/19601: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 1 lock held by syz.6.2166/20094: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 1 lock held by syz.6.2166/20097: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 1 lock held by syz.6.2166/20099: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 1 lock held by syz.6.2166/20108: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 1 lock held by syz.6.2166/20111: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 1 lock held by syz.6.2166/20114: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 1 lock held by syz.6.2166/20115: #0: ffff888025fc9358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305 2 locks held by sed/21039: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 21036 Comm: dhcpcd-run-hook Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:find_held_lock+0x2/0x80 kernel/locking/lockdep.c:5343 Code: c2 48 c7 c6 62 5e 9c 90 48 c7 c7 b5 ff c1 8d e9 74 96 3f ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 56 <41> 89 d6 41 55 49 89 cd 41 54 49 89 f4 55 8d 6a ff 48 63 c5 53 48 RSP: 0018:ffffc9000c107658 EFLAGS: 00000006 RAX: 0000000000000001 RBX: ffffffff8e5e32e0 RCX: ffffc9000c107674 RDX: 0000000000000005 RSI: ffffffff8e5e32e0 RDI: ffff88805e88a4c0 RBP: ffffffff849b1b20 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88805e88a4c0 R13: 0000000000000200 R14: 0000000000000006 R15: 0000000000000005 FS: 00007f3952992c80(0000) GS:ffff8881246d9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3952c2e7b8 CR3: 00000000326f1000 CR4: 00000000003526f0 Call Trace: __lock_release kernel/locking/lockdep.c:5535 [inline] lock_release kernel/locking/lockdep.c:5889 [inline] lock_release+0xdb/0x2e0 kernel/locking/lockdep.c:5875 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:897 [inline] avc_reclaim_node security/selinux/avc.c:487 [inline] avc_alloc_node+0x3e5/0x670 security/selinux/avc.c:507 avc_insert security/selinux/avc.c:618 [inline] avc_compute_av+0x101/0x820 security/selinux/avc.c:993 avc_perm_nonode+0xb1/0x180 security/selinux/avc.c:1117 avc_has_perm_noaudit+0x2d4/0x3b0 security/selinux/avc.c:1160 cred_has_capability security/selinux/hooks.c:1661 [inline] selinux_vm_enough_memory+0x129/0x190 security/selinux/hooks.c:2235 security_vm_enough_memory_mm+0x96/0x110 security/security.c:722 dup_mmap+0x684/0x1e20 mm/mmap.c:1768 dup_mm kernel/fork.c:1529 [inline] copy_mm kernel/fork.c:1581 [inline] copy_process+0x7451/0x7890 kernel/fork.c:2221 kernel_clone+0xfc/0x930 kernel/fork.c:2651 __do_sys_clone+0xd9/0x120 kernel/fork.c:2792 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3952b2c636 Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffefa632370 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffefa632378 RCX: 00007f3952b2c636 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00005639fe0855e0 R08: 0000000000000000 R09: 0000000000000040 R10: 00007f3952992f50 R11: 0000000000000246 R12: 00005639fe093948 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000