INFO: task udevd:16027 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:22488 pid:16027 tgid:16027 ppid:5189 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 io_schedule+0x7f/0xd0 kernel/sched/core.c:7791 folio_wait_bit_common+0x6d8/0xbc0 mm/filemap.c:1323 folio_put_wait_locked mm/filemap.c:1487 [inline] do_read_cache_folio+0x1ad/0x590 mm/filemap.c:4078 read_mapping_folio include/linux/pagemap.h:1028 [inline] read_part_sector+0xb6/0x2b0 block/partitions/core.c:722 adfspart_check_POWERTEC+0x92/0xef0 block/partitions/acorn.c:454 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x765/0x14c0 block/partitions/core.c:693 blkdev_get_whole+0x380/0x510 block/bdev.c:765 bdev_open+0x31e/0xd30 block/bdev.c:974 blkdev_open+0x470/0x610 block/fops.c:698 do_dentry_open+0x7ce/0x1420 fs/open.c:962 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:4637 [inline] path_openat+0x3486/0x3e20 fs/namei.c:4796 do_filp_open+0x22d/0x490 fs/namei.c:4823 do_sys_openat2+0x12f/0x220 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7b962a7407 RSP: 002b:00007ffe03859860 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f7b96a04880 RCX: 00007f7b962a7407 RDX: 00000000000a0800 RSI: 000055b679fb2ce0 RDI: ffffffffffffff9c RBP: 000055b679fa2910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055b679fc96d0 R13: 000055b679fb0190 R14: 0000000000000000 R15: 000055b679fc96d0 Showing all locks held in the system: 2 locks held by rcu_tasks_trace/29: #0: ffffffff8e55b0b0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{4:4}, at: rcu_tasks_one_gp+0xaf4/0xde0 kernel/rcu/tasks.h:614 #1: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:956 1 lock held by khungtaskd/31: #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by klogd/5178: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 2 locks held by getty/5578: #0: ffff88814e7b00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:6/5899: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8627198 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8627198 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 3 locks held by kworker/u8:8/6993: #0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90002ee7bc0 ((work_completion)(©->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90002ee7bc0 ((work_completion)(©->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8e55b1f0 (rcu_tasks_trace.barrier_q_mutex){+.+.}-{4:4}, at: rcu_barrier_tasks_generic+0x64/0x480 kernel/rcu/tasks.h:430 1 lock held by udevd/16027: #0: ffff888024a37358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 3 locks held by kworker/u8:19/17481: #0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90003fafbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90003fafbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 #2: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 7 locks held by kworker/u8:61/17533: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b86260d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 #3: ffffffff9a2cf758 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:818 #4: ffffffff8e3febe8 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145 #5: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #5: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #5: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: ___pte_offset_map+0x29/0x240 mm/pgtable-generic.c:288 #6: ffff88813fe64078 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #6: ffff88813fe64078 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:403 2 locks held by syz.2.5537/27848: #0: ffff88805acf3b88 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805acf3b88 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline] #0: ffff88805acf3b88 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455 #1: ffff88804fcb8260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #1: ffff88804fcb8260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_release+0x77d/0xcc0 net/packet/af_packet.c:3148 4 locks held by syz.3.5543/27866: #0: ffffffff8fa1ab30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffff8880847c80e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #1: ffff8880847c80e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #1: ffff8880847c80e8 (&dev->mutex){....}-{4:4}, at: devlink_get_from_attrs_lock+0x246/0x3b0 net/devlink/netlink.c:198 #2: ffff888033242250 (&devlink->lock_key#10){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #2: ffff888033242250 (&devlink->lock_key#10){+.+.}-{4:4}, at: devlink_get_from_attrs_lock+0x255/0x3b0 net/devlink/netlink.c:198 #3: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #3: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2155 1 lock held by syz.0.5544/27870: #0: ffffffff8e560b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3816 2 locks held by syz.4.5547/27885: #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 #1: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e560c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:956 1 lock held by syz.4.5547/27888: #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 1 lock held by syz.4.5547/27890: #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x7a4/0x1150 net/core/dev_ioctl.c:813 3 locks held by syz.4.5547/27893: #0: ffffffff8fa1ab30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8fa1a948 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8fa1a948 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8fa1a948 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1209 #2: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: __tipc_nl_compat_doit net/tipc/netlink_compat.c:358 [inline] #2: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: tipc_nl_compat_doit+0x22a/0x650 net/tipc/netlink_compat.c:393 1 lock held by syz.1.5548/27886: #0: ffff8880b863a918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:639 1 lock held by syz.1.5548/27887: #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: __tun_chr_ioctl+0x3bc/0x1e10 drivers/net/tun.c:3078 1 lock held by syz.1.5548/27889: #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 1 lock held by syz.1.5548/27891: #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 1 lock held by syz.1.5548/27894: #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f9ac708 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x7a4/0x1150 net/core/dev_ioctl.c:813 2 locks held by syz.1.5548/27895: #0: ffffffff8fa1ab30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8fa1a948 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8fa1a948 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8fa1a948 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1209 1 lock held by dhcpcd/27892: #0: ffff8880217fe260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline] #0: ffff8880217fe260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe10 net/packet/af_packet.c:3197 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 27858 Comm: syz.2.5537 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:rcu_lockdep_current_cpu_online+0x60/0x120 kernel/rcu/tree.c:4028 Code: 09 89 c3 83 f8 08 0f 83 c7 00 00 00 49 be 00 00 00 00 00 fc ff df 48 8d 1c dd d0 fd f7 8d 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 f6 d2 82 00 48 8b 03 48 8d 98 c0 08 f5 92 48 8d RSP: 0018:ffffc9000d9f73a8 EFLAGS: 00000246 RAX: 1ffffffff1beffba RBX: ffffffff8df7fdd0 RCX: 0000000080000002 RDX: 0000000000000000 RSI: ffffffff8c073960 RDI: ffffffff8c073920 RBP: 0000000000000001 R08: ffffffff823896f4 R09: ffffffff8e55a360 R10: dffffc0000000000 R11: fffff9400033d4f1 R12: 0000000000067a9e R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000001000 FS: 0000000000000000(0000) GS:ffff8881256eb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a5dda6f168 CR3: 00000000322a2000 CR4: 00000000003526f0 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 lookup_page_ext mm/page_ext.c:254 [inline] page_ext_lookup+0xe7/0x180 mm/page_ext.c:509 page_ext_iter_begin include/linux/page_ext.h:132 [inline] page_table_check_clear+0x238/0x5f0 mm/page_table_check.c:78 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline] get_and_clear_full_ptes include/linux/pgtable.h:725 [inline] zap_present_folio_ptes mm/memory.c:1630 [inline] zap_present_ptes mm/memory.c:1712 [inline] do_zap_pte_range mm/memory.c:1814 [inline] zap_pte_range mm/memory.c:1858 [inline] zap_pmd_range mm/memory.c:1950 [inline] zap_pud_range mm/memory.c:1978 [inline] zap_p4d_range mm/memory.c:1999 [inline] unmap_page_range+0x3294/0x4030 mm/memory.c:2020 unmap_single_vma mm/memory.c:2062 [inline] unmap_vmas+0x3c0/0x5c0 mm/memory.c:2104 exit_mmap+0x251/0xb30 mm/mmap.c:1277 __mmput+0x118/0x430 kernel/fork.c:1173 exit_mm+0x168/0x220 kernel/exit.c:581 do_exit+0x62e/0x2310 kernel/exit.c:959 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f354779aeb9 Code: Unable to access opcode bytes at 0x7f354779ae8f. RSP: 002b:00007f35485800e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f3547a16098 RCX: 00007f354779aeb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3547a16098 RBP: 00007f3547a16090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3547a16128 R14: 00007ffd82665eb0 R15: 00007ffd82665f98