INFO: task udevd:5910 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:25680 pid:5910 ppid:5138 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 io_schedule+0x80/0xd0 kernel/sched/core.c:9023 folio_wait_bit_common+0x714/0xfa0 mm/filemap.c:1329 folio_put_wait_locked mm/filemap.c:1493 [inline] do_read_cache_folio+0x1c0/0x7d0 mm/filemap.c:3791 read_mapping_folio include/linux/pagemap.h:898 [inline] read_part_sector+0xd2/0x340 block/partitions/core.c:718 adfspart_check_POWERTEC+0x93/0xed0 block/partitions/acorn.c:454 check_partition block/partitions/core.c:138 [inline] blk_add_partitions block/partitions/core.c:600 [inline] bdev_disk_changed+0x740/0x1420 block/partitions/core.c:689 blkdev_get_whole+0x30d/0x390 block/bdev.c:672 blkdev_get_by_dev+0x279/0x600 block/bdev.c:814 blkdev_open+0x152/0x360 block/fops.c:589 do_dentry_open+0x8c6/0x1500 fs/open.c:929 do_open fs/namei.c:3640 [inline] path_openat+0x27f1/0x3230 fs/namei.c:3797 do_filp_open+0x1f5/0x430 fs/namei.c:3824 do_sys_openat2+0x134/0x1d0 fs/open.c:1421 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+0x139/0x160 fs/open.c:1447 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4670ca7407 RSP: 002b:00007ffe21596b70 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f46713c1880 RCX: 00007f4670ca7407 RDX: 00000000000a0800 RSI: 000055e731bb2490 RDI: ffffffffffffff9c RBP: 000055e731b68910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055e731b98530 R13: 000055e731b80410 R14: 0000000000000000 R15: 000055e731b98530 Showing all locks held in the system: 3 locks held by kworker/0:0/8: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #1: ffffc900000d7d00 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc900000d7d00 ((work_completion)(&helper->damage_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #2: ffff888147e93280 (&helper->lock){+.+.}-{3:3}, at: drm_fbdev_generic_damage_blit drivers/gpu/drm/drm_fbdev_generic.c:197 [inline] #2: ffff888147e93280 (&helper->lock){+.+.}-{3:3}, at: drm_fbdev_generic_helper_fb_dirty+0x1ea/0xa70 drivers/gpu/drm/drm_fbdev_generic.c:224 2 locks held by kworker/1:0/23: 1 lock held by khungtaskd/28: #0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d132160 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 3 locks held by kworker/0:2/789: #0: ffff88801d24ed38 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff88801d24ed38 ((wq_completion)pm){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #1: ffffc90003997d00 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc90003997d00 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #2: ffff88802519d190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1040 [inline] #2: ffff88802519d190 (&dev->mutex){....}-{3:3}, at: usb_remote_wakeup+0x23/0xf0 drivers/usb/core/hub.c:3849 3 locks held by kworker/u4:6/2900: #0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c71538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #1: ffffc9000bba7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc9000bba7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #2: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286 3 locks held by kworker/u4:10/4230: 2 locks held by getty/5527: #0: ffff8880312010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 2 locks held by kworker/0:4/5815: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #1: ffffc900048bfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc900048bfd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 2 locks held by udevd/5908: 1 lock held by udevd/5910: #0: ffff888021df64c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805 3 locks held by kworker/u4:16/10097: #0: ffff88802c2fe538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff88802c2fe538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #1: ffffc90003667d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc90003667d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #2: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd4/0x1530 net/ipv6/addrconf.c:4176 2 locks held by syz.5.1356/10447: 1 lock held by syz.0.1357/10448: #0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x811/0xfa0 net/core/rtnetlink.c:6473 1 lock held by syz.0.1357/10450: #0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x811/0xfa0 net/core/rtnetlink.c:6473 2 locks held by syz.4.1359/10452: #0: ffff88807ddce4b8 (&nft_net->commit_mutex){+.+.}-{3:3}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:10851 #1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #1: ffffffff8d137b38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 1 lock held by syz.4.1359/10454: #0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0xd3c/0x2df0 net/ipv4/ip_sockglue.c:1046 1 lock held by syz.4.1359/10456: #0: ffffffff8e3c3a88 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0xd3c/0x2df0 net/ipv4/ip_sockglue.c:1046 6 locks held by syz.4.1359/10459: #0: ffffffff8d126480 (console_lock){+.+.}-{0:0}, at: con_font_set drivers/tty/vt/vt.c:4623 [inline] #0: ffffffff8d126480 (console_lock){+.+.}-{0:0}, at: con_font_op+0xa90/0xfa0 drivers/tty/vt/vt.c:4676 #1: ffff888147e93280 (&helper->lock){+.+.}-{3:3}, at: drm_fb_helper_pan_display+0xbe/0xbd0 drivers/gpu/drm/drm_fb_helper.c:1439 #2: ffff8880212cc1b0 (&dev->master_mutex){+.+.}-{3:3}, at: drm_master_internal_acquire+0x20/0x70 drivers/gpu/drm/drm_auth.c:458 #3: ffff888147e93098 (&client->modeset_mutex){+.+.}-{3:3}, at: drm_client_modeset_commit_locked+0x4c/0x4c0 drivers/gpu/drm/drm_client_modeset.c:1158 #4: ffffc900042ef4b0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_client_modeset_commit_atomic+0x111/0x7b0 drivers/gpu/drm/drm_client_modeset.c:996 #5: ffff888147e920b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0x2b0/0x630 drivers/gpu/drm/drm_modeset_lock.c:314 3 locks held by dhcpcd-run-hook/10455: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10447 Comm: syz.5.1356 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:60 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:178 [inline] RIP: 0010:kasan_check_range+0x52/0x290 mm/kasan/generic.c:187 Code: f9 49 c1 e9 2f 41 81 f9 ff ff 01 00 0f 82 ff 01 00 00 49 89 ff 49 c1 ef 03 49 ba 00 00 00 00 00 fc ff df 4f 8d 1c 17 49 ff c8 <4d> 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc ff df 4d 8d 34 19 4d RSP: 0018:ffffc900001f0b48 EFLAGS: 00000086 RAX: 00000000ffffff01 RBX: ffffffff975a1a18 RCX: ffffffff8169844f RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc900001f0bc0 RBP: ffffc900001f0c30 R08: ffffc900001f0bc3 R09: 000000000001ffff R10: dffffc0000000000 R11: fffff5200003e178 R12: 1ffff9200003e174 R13: dffffc0000000000 R14: 1ffffffff2eb4345 R15: 1ffff9200003e178 FS: 00007f32a3d436c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f54aaef07e8 CR3: 000000006a190000 CR4: 00000000003506e0 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1295 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock+0x11f/0x2c0 kernel/locking/spinlock_debug.c:115 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xc0/0x100 kernel/locking/spinlock.c:162 debug_object_deactivate+0x67/0x390 lib/debugobjects.c:764 debug_hrtimer_deactivate kernel/time/hrtimer.c:455 [inline] __run_hrtimer kernel/time/hrtimer.c:1718 [inline] __hrtimer_run_queues+0x2cb/0xc40 kernel/time/hrtimer.c:1814 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline] __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x10/0x90 kernel/kcov.c:313 Code: 11 10 48 89 74 11 18 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 60 8a 7c 7e <65> 8b 0d 61 8a 7c 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 RSP: 0018:ffffc90003516510 EFLAGS: 00000246 RAX: ffffffff813b6483 RBX: 1ffff920006a2cc9 RCX: 0000000000080000 RDX: ffff888059781e00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffff888059781e00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000002 R12: ffffc90003518000 R13: 1ffff920006a2ccb R14: ffffc90003510000 R15: ffffc90003516648 on_stack arch/x86/include/asm/stacktrace.h:58 [inline] stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] deref_stack_reg+0x93/0x240 arch/x86/kernel/unwind_orc.c:403 unwind_next_frame+0x1789/0x2970 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 kernfs_put+0x1d3/0x360 fs/kernfs/dir.c:578 kernfs_remove_by_name_ns+0xe4/0x150 fs/kernfs/dir.c:1696 kernfs_remove_by_name include/linux/kernfs.h:624 [inline] remove_files fs/sysfs/group.c:28 [inline] sysfs_remove_group+0xfc/0x2a0 fs/sysfs/group.c:292 sysfs_remove_groups+0x54/0xa0 fs/sysfs/group.c:316 device_remove_groups drivers/base/core.c:2792 [inline] device_remove_attrs+0x1cc/0x280 drivers/base/core.c:2967 device_del+0x51a/0x910 drivers/base/core.c:3886 unregister_netdevice_many_notify+0x143f/0x1900 net/core/dev.c:11154 rtnl_newlink_create net/core/rtnetlink.c:3552 [inline] __rtnl_newlink net/core/rtnetlink.c:3741 [inline] rtnl_newlink+0x1d5b/0x20a0 net/core/rtnetlink.c:3754 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6476 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmsg net/socket.c:2677 [inline] __do_sys_sendmsg net/socket.c:2686 [inline] __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f32a2d9ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f32a3d43028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f32a3015fa0 RCX: 00007f32a2d9ce59 RDX: 0000000000040000 RSI: 00002000000002c0 RDI: 0000000000000003 RBP: 00007f32a2e32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f32a3016038 R14: 00007f32a3015fa0 R15: 00007ffc1baefb88