INFO: task syz-executor:15694 blocked for more than 143 seconds. Not tainted 6.13.0-rc1-next-20241205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20272 pid:15694 tgid:15694 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5371 [inline] __schedule+0x189f/0x4c80 kernel/sched/core.c:6758 __schedule_loop kernel/sched/core.c:6835 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6850 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:216 sync_inodes_sb+0x28d/0xb50 fs/fs-writeback.c:2821 sync_filesystem+0x176/0x230 fs/sync.c:64 generic_shutdown_super+0x72/0x2d0 fs/super.c:621 kill_block_super+0x44/0x90 fs/super.c:1710 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x24f/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7d1f17fed9 RSP: 002b:00007ffc25d1e318 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f7d1f1f3b14 RCX: 00007f7d1f17fed9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000005 R08: 00007ffc25d1c0b7 R09: 00007ffc25d1f5d0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc25d1f5d0 R13: 00007f7d1f1f3ab4 R14: 0000555572ebc4a8 R15: 00007ffc25d20690 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e9374a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e9374a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e9374a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 1 lock held by udevd/5202: 2 locks held by getty/5584: #0: ffff8880318060a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by kworker/u8:7/5899: #0: ffff88801e69d948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801e69d948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc900043efd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900043efd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 2 locks held by syz-executor/15694: #0: ffff888057cb20e0 (&type->s_umount_key#48){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888057cb20e0 (&type->s_umount_key#48){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888057cb20e0 (&type->s_umount_key#48){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffff8881427e27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline] #1: ffff8881427e27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819 1 lock held by syz-executor/16808: #0: ffffffff8e93c9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93c9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 2 locks held by segctord/16978: 3 locks held by syz.3.2665/18961: 1 lock held by syz.9.2664/18976: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc1-next-20241205-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5846 Comm: udevd Not tainted 6.13.0-rc1-next-20241205-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:unwind_next_frame+0x17dc/0x22d0 arch/x86/kernel/unwind_orc.c:665 Code: b6 04 20 84 c0 0f 85 36 08 00 00 48 8b 6c 24 08 8b 84 24 84 00 00 00 39 45 00 0f 85 0a 01 00 00 48 8b 44 24 58 42 80 3c 20 00 <74> 0a 48 8b 7c 24 78 e8 58 e5 b9 00 4c 8b 7d 38 48 8d 7d 08 48 89 RSP: 0018:ffffc900041ef3d0 EFLAGS: 00000246 RAX: 1ffff9200083de9b RBX: ffffffff90afdcda RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffc900041e8000 RDI: ffffc900041ef858 RBP: ffffc900041ef4a0 R08: ffffc900041ef858 R09: 0000000000000000 R10: ffffc900041ef4f0 R11: fffff5200083dea0 R12: dffffc0000000000 R13: ffffc900041ef4a0 R14: ffffffff8205ae40 R15: ffffc900041ef4f0 FS: 00007f0348e9cc80(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa209d0cab8 CR3: 0000000065000000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4700 file_free+0x24/0x200 fs/file_table.c:68 path_openat+0x2ee0/0x3590 fs/namei.c:3996 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1395 do_sys_open fs/open.c:1410 [inline] __do_sys_openat fs/open.c:1426 [inline] __se_sys_openat fs/open.c:1421 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1421 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0348b16ab9 Code: 00 00 00 44 8b 54 24 58 48 89 44 24 30 48 8d 44 24 40 48 89 44 24 38 64 8b 04 25 18 00 00 00 85 c0 75 21 b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 40 a3 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffe86568860 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffe8656a9c8 RCX: 00007f0348b16ab9 RDX: 0000000000080000 RSI: 00007f0348f8add8 RDI: 000000000000000b RBP: 0000564c5c462780 R08: 0000564c5c443560 R09: 00007f0348bf1b20 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000b R13: 00007f0348f8add8 R14: 0000000000080000 R15: 0000000000000000