INFO: task kworker/u4:11:27236 blocked for more than 146 seconds. Not tainted 5.15.110-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:11 state:D stack:22368 pid:27236 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:4) Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 schedule+0x11b/0x1f0 kernel/sched/core.c:6455 rwsem_down_write_slowpath+0xebb/0x15c0 kernel/locking/rwsem.c:1157 __down_write_common kernel/locking/rwsem.c:1284 [inline] __down_write kernel/locking/rwsem.c:1293 [inline] down_write+0x164/0x170 kernel/locking/rwsem.c:1542 f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:529 f2fs_write_inode+0x4c3/0x540 fs/f2fs/inode.c:727 write_inode fs/fs-writeback.c:1475 [inline] __writeback_single_inode+0x644/0xe30 fs/fs-writeback.c:1680 writeback_sb_inodes+0xbf0/0x1a50 fs/fs-writeback.c:1905 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1976 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2081 wb_check_start_all fs/fs-writeback.c:2203 [inline] wb_do_writeback fs/fs-writeback.c:2229 [inline] wb_workfn+0x9f4/0x1130 fs/fs-writeback.c:2263 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2306 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 INFO: task syz-executor.0:32627 blocked for more than 147 seconds. Not tainted 5.15.110-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:22176 pid:32627 ppid: 3534 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 schedule+0x11b/0x1f0 kernel/sched/core.c:6455 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x293/0xab0 fs/fs-writeback.c:2745 iterate_supers+0x127/0x1e0 fs/super.c:705 ksys_sync+0xb9/0x1c0 fs/sync.c:102 __do_sys_sync+0xa/0x10 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7efe2b3c0169 RSP: 002b:00007efe29932168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007efe2b4dff80 RCX: 00007efe2b3c0169 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007efe2b41bca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffef38028ef R14: 00007efe29932300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c91c4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3262: #0: ffff88814ad47098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900024bb2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147 2 locks held by syz-executor.1/3541: #0: ffff88801b545118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912 #1: ffff8881470a3468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa9/0xbe0 drivers/block/loop.c:1365 2 locks held by kworker/0:12/22251: #0: ffff888011c66538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc900036dfd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 1 lock held by syz-executor.3/24006: 2 locks held by kworker/1:8/25108: 3 locks held by kworker/0:20/25216: #0: ffff888011c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc90004db7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 #2: ffffffff8c920a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffffffff8c920a28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:840 4 locks held by kworker/u4:11/27236: #0: ffff888142184938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc900038ffd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 #2: ffff8880769540e0 (&type->s_umount_key#64){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418 #3: ffff888046801108 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:529 2 locks held by kworker/u4:14/29190: 2 locks held by syz-executor.4/32248: 2 locks held by syz-executor.0/32627: #0: ffff8880769540e0 (&type->s_umount_key#64){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:703 #1: ffff888146ff27d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff888146ff27d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2743 2 locks held by kworker/1:2/395: #0: ffff888011c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc90004ec7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 2 locks held by kworker/1:16/491: #0: ffff888011c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2279 #1: ffffc9000321fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2281 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.110-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1316 Comm: syz-executor.5 Not tainted 5.15.110-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0033:0x7f5c42cef23c Code: 01 c2 49 3b 55 08 77 56 8d 55 ff 85 ed 74 35 0f 1f 80 00 00 00 00 48 39 c1 77 1c 49 8b 75 00 49 89 c1 49 29 c9 46 0f b6 0c 0e <45> 84 c9 74 08 44 88 0c 06 49 8b 45 10 48 83 c0 01 49 89 45 10 83 RSP: 002b:00007f5c412c3600 EFLAGS: 00000206 RAX: 000000000040c1c1 RBX: 00007f5c412c3660 RCX: 0000000000000001 RDX: 000000000000001a RSI: 00007f5c38ea4000 RDI: 00007f5c412c3700 RBP: 0000000000000102 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 00007f5c412c3670 R12: 00007f5c412c3670 R13: 00007f5c412c3700 R14: 0000000000000001 R15: 0000000000000000 FS: 00007f5c412c4700 GS: 0000000000000000