INFO: task kworker/u4:10:4416 blocked for more than 143 seconds. Not tainted 5.15.173-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:10 state:D stack:20152 pid: 4416 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:5) Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165 f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:528 f2fs_write_inode+0x4c3/0x540 fs/f2fs/inode.c:736 write_inode fs/fs-writeback.c:1495 [inline] __writeback_single_inode+0x644/0xe30 fs/fs-writeback.c:1705 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106 wb_check_background_flush fs/fs-writeback.c:2172 [inline] wb_do_writeback fs/fs-writeback.c:2260 [inline] wb_workfn+0xd07/0x1130 fs/fs-writeback.c:2288 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Showing all locks held in the system: 2 locks held by kworker/0:1/13: 1 lock held by khungtaskd/27: #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3937: #0: ffff88814ce82098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025ae2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 2 locks held by kworker/0:3/4156: #0: ffff888017072138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90002e87d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by syz-executor/4167: #0: ffff888020d3c518 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912 #1: ffff888147a26468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xa9/0xbe0 drivers/block/loop.c:1365 4 locks held by kworker/u4:10/4416: #0: ffff8881447ac938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003017d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff88807b8780e0 (&type->s_umount_key#52){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418 #3: ffff888079b151b0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:528 2 locks held by kworker/u4:17/5813: #0: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #1: ffff8880b9027848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x53d/0x810 kernel/sched/psi.c:891 5 locks held by syz.5.870/8027: 1 lock held by syz.8.1246/9480: #0: ffff888074528210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #0: ffff888074528210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline] #0: ffff888074528210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x98/0x230 net/socket.c:1336 1 lock held by syz.7.1256/9515: #0: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 1 lock held by dhcpcd-run-hook/9540: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 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: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: 8027 Comm: syz.5.870 Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:55 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x30/0x290 mm/kasan/generic.c:189 Code: b0 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 0f 82 59 02 00 00 48 89 fd 48 c1 ed 2f 81 fd ff ff 01 00 0f 82 46 02 00 00 <48> 89 fb 48 c1 eb 03 49 b8 00 00 00 00 00 fc ff df 4e 8d 0c 03 4c RSP: 0018:ffffc90002f96c38 EFLAGS: 00000246 RAX: 1ffff1100fcb2d01 RBX: ffff8880638dd400 RCX: ffffffff8a3d3430 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88801f02d458 RBP: 000000000001ffff R08: dffffc0000000000 R09: fffffbfff20ec846 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100b41f4aa R13: ffff88801f02d458 R14: 1ffff1100b41f4ab R15: ffff88801f02d458 FS: 00007f9be36e56c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f124c317ab8 CR3: 0000000053c8f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_long_add_return_acquire include/linux/atomic/atomic-instrumented.h:1225 [inline] rwsem_read_trylock kernel/locking/rwsem.c:243 [inline] __down_read_common kernel/locking/rwsem.c:1238 [inline] __down_read kernel/locking/rwsem.c:1252 [inline] down_read+0x60/0x2e0 kernel/locking/rwsem.c:1500 check_valid_map fs/f2fs/gc.c:881 [inline] gc_data_segment fs/f2fs/gc.c:1451 [inline] do_garbage_collect+0x2091/0x7540 fs/f2fs/gc.c:1671 f2fs_gc+0x9d2/0x1c30 fs/f2fs/gc.c:1765 f2fs_balance_fs+0x4e8/0x6a0 fs/f2fs/segment.c:529 f2fs_map_blocks+0x265b/0x3720 fs/f2fs/data.c:1700 expand_inode_data+0x5dd/0xa40 fs/f2fs/file.c:1709 f2fs_fallocate+0x42d/0x910 fs/f2fs/file.c:1805 vfs_fallocate+0x54a/0x6b0 fs/open.c:308 do_vfs_ioctl+0x2317/0x2b70 fs/ioctl.c:853 __do_sys_ioctl fs/ioctl.c:872 [inline] __se_sys_ioctl+0x81/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f9be586d819 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9be36e5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9be5a24fa0 RCX: 00007f9be586d819 RDX: 00000000200000c0 RSI: 0000000040305828 RDI: 0000000000000004 RBP: 00007f9be58e075e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f9be5a24fa0 R15: 00007ffdca70f518