INFO: task kworker/u8:13:3539 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:13 state:D stack:22784 pid:3539 tgid:3539 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:8) Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x14fb/0x52c0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 io_schedule+0x80/0xe0 kernel/sched/core.c:7831 TXN_SLEEP_DROP_LOCK fs/jfs/jfs_txnmgr.c:125 [inline] txBegin+0x27d/0xc00 fs/jfs/jfs_txnmgr.c:375 jfs_commit_inode+0x1b3/0x530 fs/jfs/inode.c:107 jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138 write_inode fs/fs-writeback.c:1581 [inline] __writeback_single_inode+0x75d/0x11a0 fs/fs-writeback.c:1812 writeback_sb_inodes+0x944/0x1970 fs/fs-writeback.c:2040 wb_writeback+0x456/0xb70 fs/fs-writeback.c:2226 wb_do_writeback fs/fs-writeback.c:2373 [inline] wb_workfn+0x41a/0xf60 fs/fs-writeback.c:2413 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz-executor:6937 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22496 pid:6937 tgid:6937 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x14fb/0x52c0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 wb_wait_for_completion+0x372/0x690 fs/fs-writeback.c:226 __writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2837 sync_filesystem+0xa2/0x250 fs/sync.c:54 generic_shutdown_super+0x77/0x2d0 fs/super.c:625 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __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 include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3ca98dd897 RSP: 002b:00007ffc0d488cc8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f3ca9971ef0 RCX: 00007f3ca98dd897 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc0d488d80 RBP: 00007ffc0d488d80 R08: 00007ffc0d489d80 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc0d489e10 R13: 00007f3ca9971ef0 R14: 00000000000454c2 R15: 00007ffc0d489e50 Showing all locks held in the system: 1 lock held by khungtaskd/37: #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:13/3539: #0: ffff88801aedc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88801aedc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc9000eea7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc9000eea7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 2 locks held by getty/5551: #0: ffff8880288520a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by udevd/5856: 1 lock held by syz-executor/6937: #0: ffff88803c9e40d0 (&type->s_umount_key#90){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88803c9e40d0 (&type->s_umount_key#90){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88803c9e40d0 (&type->s_umount_key#90){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 1 lock held by udevd/8195: 2 locks held by syz-executor/9765: 1 lock held by syz.9.642/9922: #0: ffff88803c9e40d0 (&type->s_umount_key#90){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #0: ffff88803c9e40d0 (&type->s_umount_key#90){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 2 locks held by syz.0.925/11809: 2 locks held by syz.4.921/11811: 9 locks held by syz.6.928/11823: 5 locks held by dhcpcd-run-hook/11825: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11825 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:222 [inline] RIP: 0010:unwind_next_frame+0x1f5/0x23c0 arch/x86/kernel/unwind_orc.c:510 Code: fc 48 63 26 8b 0f 93 c1 08 c1 0f 85 05 01 00 00 48 c7 c0 00 00 00 81 4d 89 e7 49 29 c7 49 c1 ef 08 8b 15 9e 71 09 0c 8d 42 ff <44> 39 f8 0f 86 78 04 00 00 44 89 f8 4c 8d 2c 85 d4 07 9b 90 4c 89 RSP: 0018:ffffc900040d6fb8 EFLAGS: 00000203 RAX: 00000000000a2664 RBX: 0000000000000001 RCX: 0000000080000000 RDX: 00000000000a2665 RSI: ffffffff8ba64460 RDI: ffffffff8ba64420 RBP: dffffc0000000000 R08: ffffffff81766a15 R09: ffffffff8ddcd780 R10: ffffc900040d70d8 R11: ffffffff81af6870 R12: ffffffff821476ef R13: ffffc900040d70d8 R14: ffffc900040d7088 R15: 0000000000011476 FS: 0000000000000000(0000) GS:ffff888126343000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f92217be286 CR3: 0000000059f86000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 slab_free_hook mm/slub.c:2648 [inline] slab_free mm/slub.c:6124 [inline] kmem_cache_free+0x4fb/0x6b0 mm/slub.c:6254 anon_vma_free mm/rmap.c:137 [inline] __put_anon_vma+0x12a/0x310 mm/rmap.c:2889 put_anon_vma mm/internal.h:215 [inline] unlink_anon_vmas+0x58b/0x730 mm/rmap.c:529 free_pgtables+0x836/0xb70 mm/memory.c:427 exit_mmap+0x490/0xa10 mm/mmap.c:1314 __mmput+0xcb/0x3d0 kernel/fork.c:1174 exec_mmap+0x3b2/0x440 fs/exec.c:893 begin_new_exec+0x1350/0x24b0 fs/exec.c:1148 load_elf_binary+0xa50/0x29b0 fs/binfmt_elf.c:1010 search_binary_handler fs/exec.c:1664 [inline] exec_binprm fs/exec.c:1696 [inline] bprm_execve+0x93d/0x1460 fs/exec.c:1748 do_execveat_common+0x50d/0x690 fs/exec.c:1846 __do_sys_execve fs/exec.c:1930 [inline] __se_sys_execve fs/exec.c:1924 [inline] __x64_sys_execve+0x97/0xc0 fs/exec.c:1924 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9221704107 Code: Unable to access opcode bytes at 0x7f92217040dd. RSP: 002b:00007fffb7e4a748 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 00005598148c2078 RCX: 00007f9221704107 RDX: 00005598148c20a0 RSI: 00005598148c2078 RDI: 00005598148c2130 RBP: 00005598148c2130 R08: 00007fffb7e4fe75 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 00005598148c20a0 R13: 00007f92218c9e8b R14: 00005598148c20a0 R15: 0000000000000000