INFO: task jfsCommit:278 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jfsCommit state:D stack:27200 pid: 278 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356 txUnlock+0x244/0xcb0 fs/jfs/jfs_txnmgr.c:930 txLazyCommit fs/jfs/jfs_txnmgr.c:2717 [inline] jfs_lazycommit+0x583/0xb20 fs/jfs/jfs_txnmgr.c:2767 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 INFO: task kworker/u4:5:4272 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:5 state:D stack:23904 pid: 4272 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356 lock_page include/linux/pagemap.h:625 [inline] write_cache_pages+0x41d/0xfa0 mm/page-writeback.c:2244 generic_writepages mm/page-writeback.c:2368 [inline] do_writepages+0x4fa/0x6d0 mm/page-writeback.c:2388 __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657 writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1940 __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011 wb_writeback+0x455/0xb90 fs/fs-writeback.c:2116 wb_check_background_flush fs/fs-writeback.c:2182 [inline] wb_do_writeback fs/fs-writeback.c:2270 [inline] wb_workfn+0xb47/0xe60 fs/fs-writeback.c:2298 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 INFO: task syz.0.84:4680 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.84 state:D stack:25160 pid: 4680 ppid: 4180 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503 wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356 lock_page include/linux/pagemap.h:625 [inline] release_metapage+0x11f/0xe10 fs/jfs/jfs_metapage.c:736 discard_metapage fs/jfs/jfs_metapage.h:88 [inline] __get_metapage+0xbeb/0x1060 fs/jfs/jfs_metapage.c:645 dtSearch+0x5d5/0x2050 fs/jfs/jfs_dtree.c:624 jfs_lookup+0x152/0x380 fs/jfs/namei.c:1459 __lookup_slow+0x27d/0x3d0 fs/namei.c:1671 lookup_slow+0x53/0x70 fs/namei.c:1688 walk_component+0x319/0x460 fs/namei.c:1984 lookup_last fs/namei.c:2439 [inline] path_lookupat+0x169/0x440 fs/namei.c:2463 filename_lookup+0x1e2/0x4f0 fs/namei.c:2492 user_path_at_empty+0x40/0x190 fs/namei.c:2891 user_path_at include/linux/namei.h:57 [inline] do_mount fs/namespace.c:3374 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x297/0x3c0 fs/namespace.c:3562 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f061e5e5749 RSP: 002b:00007f061c84c038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f061e83bfa0 RCX: 00007f061e5e5749 RDX: 0000000000000000 RSI: 0000200000000140 RDI: 0000200000000100 RBP: 00007f061e669f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000002000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f061e83c038 R14: 00007f061e83bfa0 R15: 00007ffeb1f00a68 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by dhcpcd/3851: #0: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x258/0x1a70 net/ipv4/devinet.c:1076 2 locks held by getty/3943: #0: ffff88814d13b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by kworker/0:3/4171: #0: ffff888141fe6d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90002d9fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff88802384d220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #2: ffff88802384d220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1a7/0x5560 drivers/usb/core/hub.c:5827 1 lock held by syz-executor/4187: #0: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845 3 locks held by kworker/u5:8/4198: #0: ffff8880789fc938 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000300fd00 ((work_completion)(&hdev->power_on)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888054218ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_open+0xa4/0x1270 net/bluetooth/hci_core.c:1446 3 locks held by kworker/u4:5/4272: #0: ffff888141b88138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000340fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff8880262bc0e0 (&type->s_umount_key#70){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418 2 locks held by kworker/0:12/4519: #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90002f0fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 1 lock held by syz.0.84/4680: #0: ffff888074cbeb40 (&type->i_mutex_dir_key#12){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:797 [inline] #0: ffff888074cbeb40 (&type->i_mutex_dir_key#12){++++}-{3:3}, at: lookup_slow+0x46/0x70 fs/namei.c:1687 3 locks held by kworker/u4:10/5345: #0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90003bffd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 4 locks held by kworker/u4:12/5348: 3 locks held by kworker/1:14/5474: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000333fd00 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888075f8c400 (&nsim_dev->port_list_lock#2){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xb40 drivers/net/netdevsim/dev.c:757 2 locks held by kworker/1:16/5476: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000337fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 2 locks held by syz-executor/6654: #0: ffff88801fcd7518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915 #1: ffff888147a2b468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366 8 locks held by syz-executor/8190: #0: ffff88807ee4e460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590 #1: ffff8880622d4488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287 #2: ffff888148613ae8 (kn->active#296){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x208/0x4c0 fs/kernfs/file.c:288 #3: ffffffff8cb72648 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xce/0x380 drivers/net/netdevsim/bus.c:344 #4: ffff888075f8b178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #4: ffff888075f8b178 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1044 [inline] #4: ffff888075f8b178 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb0/0x750 drivers/base/dd.c:1259 #5: ffff888075f8c400 (&nsim_dev->port_list_lock#2){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline] #5: ffff888075f8c400 (&nsim_dev->port_list_lock#2){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x115/0x240 drivers/net/netdevsim/dev.c:1561 #6: ffffffff8d232788 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3b/0x150 drivers/net/netdevsim/netdev.c:381 #7: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #7: ffffffff8c1211a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 2 locks held by syz.2.662/8329: #0: ffff88802539f098 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:300 [inline] #0: ffff88802539f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:356 [inline] #0: ffff88802539f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:377 [inline] #0: ffff88802539f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0xb3/0x200 drivers/tty/tty_ldisc.c:802 #1: ffff888078ec6098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:306 [inline] #1: ffff888078ec6098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:358 [inline] #1: ffff888078ec6098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:377 [inline] #1: ffff888078ec6098 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0xd7/0x200 drivers/tty/tty_ldisc.c:802 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4292 Comm: udevd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:rcu_lock_acquire+0x11/0x30 include/linux/rcupdate.h:313 Code: 07 80 c1 03 38 c1 7c bd e8 8c 93 3a 00 eb b6 66 2e 0f 1f 84 00 00 00 00 00 e8 eb 2a f6 ff e8 e6 2a f6 ff 48 c7 c7 20 c7 11 8c <31> f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 68 25 a1 81 81 e8 a6 RSP: 0018:ffffc9000404f8d8 EFLAGS: 00000293 RAX: ffffffff8181a12a RBX: ffffc900010f6000 RCX: ffff88807e305940 RDX: 0000000000000000 RSI: 0000000000000754 RDI: ffffffff8c11c720 RBP: ffffc9000404f988 R08: ffffffff89c000ca R09: 0000000000000002 R10: 0000000022072ecc R11: 00000000b4779c52 R12: 1ffff92000809f20 R13: dffffc0000000000 R14: ffff88805b89a000 R15: ffffffff839c98c8 FS: 00007f80baa89880(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555563185608 CR3: 0000000022816000 CR4: 00000000003506f0 Call Trace: rcu_read_lock include/linux/rcupdate.h:740 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1877 [inline] bpf_trace_run2+0x97/0x2d0 kernel/trace/bpf_trace.c:1915 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:118 trace_kfree include/trace/events/kmem.h:118 [inline] kfree+0x25f/0x2a0 mm/slub.c:4554 tomoyo_realpath_from_path+0x5d8/0x610 security/tomoyo/realpath.c:291 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x1cd/0x510 security/tomoyo/file.c:822 tomoyo_path_unlink+0x9f/0xe0 security/tomoyo/tomoyo.c:149 security_path_unlink+0xd8/0x130 security/security.c:1170 do_unlinkat+0x2ed/0x6f0 fs/namei.c:4352 __do_sys_unlink fs/namei.c:4404 [inline] __se_sys_unlink fs/namei.c:4402 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4402 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f80babe5937 Code: 00 00 e9 a9 fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 5f 00 00 00 0f 05 c3 0f 1f 84 00 00 00 00 00 b8 57 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 91 b4 0d 00 f7 d8 64 89 02 b8 RSP: 002b:00007ffd0600e928 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 00007ffd0600e950 RCX: 00007f80babe5937 RDX: fffffffffffffe68 RSI: 00007ffd0600ed50 RDI: 0000558259145040 RBP: 0000000000000000 R08: 000055825913d340 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000558259146ba0 R13: 00007ffd0600f550 R14: 0000000000000000 R15: 00007ffd0600ed50