INFO: task syz-executor:4248 blocked for more than 144 seconds. Not tainted 6.1.131-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20472 pid:4248 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 schedule+0xbf/0x180 kernel/sched/core.c:6636 wb_wait_for_completion+0x162/0x290 fs/fs-writeback.c:191 __writeback_inodes_sb_nr+0x2ce/0x370 fs/fs-writeback.c:2653 sync_filesystem+0xa0/0x220 fs/sync.c:54 generic_shutdown_super+0x6b/0x340 fs/super.c:474 kill_block_super+0x7a/0xe0 fs/super.c:1470 deactivate_locked_super+0xa0/0x110 fs/super.c:332 cleanup_mnt+0x490/0x520 fs/namespace.c:1186 task_work_run+0x246/0x300 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f251718e497 RSP: 002b:00007ffc6fcdbf18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f251720e08c RCX: 00007f251718e497 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc6fcdbfd0 RBP: 00007ffc6fcdbfd0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc6fcdd060 R13: 00007f251720e08c R14: 00000000000dea11 R15: 00007ffc6fcdd0a0 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32e890 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32f090 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 2 locks held by getty/4009: #0: ffff888030c47098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198 1 lock held by syz-executor/4248: #0: ffff88801bad40e0 (&type->s_umount_key#65){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362 2 locks held by kworker/u4:19/4593: 3 locks held by kworker/u4:20/7400: #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc900033b7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8d333bc0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5f0 kernel/rcu/tree.c:4019 3 locks held by kworker/1:1/13279: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003617d20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffff8880b8f28358 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x120/0x260 kernel/time/timer.c:999 2 locks held by kworker/u4:22/13663: #0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003cd7d20 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 1 lock held by syz-executor/14247: 1 lock held by sed/14573: 1 lock held by modprobe/14575: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ca/0x430 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4593 Comm: kworker/u4:19 Not tainted 6.1.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:xas_load+0x8e/0x140 lib/xarray.c:240 Code: 83 fb 02 0f 85 a8 00 00 00 4d 8d 7c 24 fe 48 8b 44 24 10 42 0f b6 04 30 84 c0 75 57 48 8b 04 24 0f b6 18 4d 89 fd 49 c1 ed 03 <43> 0f b6 44 35 00 84 c0 75 55 41 0f b6 2f 0f b6 db 89 df 89 ee e8 RSP: 0018:ffffc90004b6f130 EFLAGS: 00000a02 RAX: ffffc90004b6f1f0 RBX: 0000000000000000 RCX: ffff888027cfd940 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000002 RBP: ffffc90004b6f290 R08: ffffffff8aad9757 R09: fffffbfff225724d R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888055113702 R13: 1ffff1100aa226e0 R14: dffffc0000000000 R15: ffff888055113700 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffaf0bbd3b0 CR3: 000000004d1d3000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mapping_get_entry mm/filemap.c:1881 [inline] __filemap_get_folio+0x22c/0xe80 mm/filemap.c:1943 pagecache_get_page+0x28/0x250 mm/folio-compat.c:110 find_or_create_page include/linux/pagemap.h:646 [inline] grow_dev_page fs/buffer.c:946 [inline] grow_buffers fs/buffer.c:1011 [inline] __getblk_slow fs/buffer.c:1038 [inline] __getblk_gfp+0x211/0xa20 fs/buffer.c:1333 __bread_gfp+0x2a/0x370 fs/buffer.c:1367 sb_bread include/linux/buffer_head.h:338 [inline] __fat_write_inode+0x281/0x9d0 fs/fat/inode.c:870 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677 writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903 wb_writeback+0x49d/0xe10 fs/fs-writeback.c:2077 wb_do_writeback fs/fs-writeback.c:2220 [inline] wb_workfn+0x427/0x1020 fs/fs-writeback.c:2260 process_one_work+0x917/0x1260 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295