INFO: task kworker/u4:4:2640 blocked for more than 143 seconds. Not tainted 5.15.165-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:19744 pid: 2640 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) 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: 1 lock held by khungtaskd/27: #0: ffffffff8c91fbe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:4/2640: #0: ffff888142fca138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000acffd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff888016fce0e0 (&type->s_umount_key#43){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418 #3: ffff8880247fd108 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:528 2 locks held by getty/3323: #0: ffff888024675098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc9000229b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 6 locks held by syz-executor918/3582: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.165-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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: 3582 Comm: syz-executor918 Not tainted 5.15.165-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:__lock_acquire+0xd0f/0x1ff0 kernel/locking/lockdep.c:4985 Code: be 08 00 00 00 e8 f1 6b 67 00 48 bf 00 00 00 00 00 fc ff df 48 63 c5 48 8b 6c 24 18 48 0f a3 05 97 50 64 0e 0f 83 4c 08 00 00 <48> 81 c5 e0 0a 00 00 49 89 ee 49 c1 ee 03 41 80 3c 3e 00 74 12 48 RSP: 0018:ffffc900030d6140 EFLAGS: 00000057 RAX: 0000000000000000 RBX: ffff888012b38be0 RCX: ffffffff8162c00f RDX: 0000000000000000 RSI: 0000000000000008 RDI: dffffc0000000000 RBP: ffff888012b38000 R08: dffffc0000000000 R09: fffffbfff1f8e219 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000006 R13: ffff888012b38ae8 R14: 0000000000000006 R15: ffff888012b38c00 FS: 0000555555e42380(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe54921228 CR3: 0000000019d25000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:961 [inline] debug_check_no_obj_freed+0xd8/0x4e0 lib/debugobjects.c:1002 slab_free_hook mm/slub.c:1680 [inline] slab_free_freelist_hook+0x86/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kmem_cache_free+0x91/0x1f0 mm/slub.c:3515 submit_bio_checks+0x323/0x1940 block/blk-core.c:899 __submit_bio+0x5a1/0x850 block/blk-core.c:911 __submit_bio_noacct_mq block/blk-core.c:997 [inline] submit_bio_noacct+0x955/0xb30 block/blk-core.c:1027 submit_bio+0x2dd/0x560 block/blk-core.c:1089 f2fs_submit_page_read+0x24c/0x2c0 fs/f2fs/data.c:1050 f2fs_get_read_data_page+0x455/0x6b0 fs/f2fs/data.c:1224 f2fs_get_lock_data_page+0x54/0x250 fs/f2fs/data.c:1271 move_data_page fs/f2fs/gc.c:1336 [inline] gc_data_segment fs/f2fs/gc.c:1547 [inline] do_garbage_collect+0x3645/0x7540 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+0x2d56/0x3720 fs/f2fs/data.c:1746 expand_inode_data+0x5dd/0xa40 fs/f2fs/file.c:1706 f2fs_fallocate+0x42d/0x910 fs/f2fs/file.c:1802 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: 0033:0x7f64a1650b99 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd2b3533f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f64a1650b99 RDX: 0000000020000240 RSI: 0000000040305828 RDI: 0000000000000004 RBP: 00007f64a16c95f0 R08: 0000555555e434c0 R09: 0000555555e434c0 R10: 0000555555e434c0 R11: 0000000000000246 R12: 00007ffd2b353420 R13: 00007ffd2b353648 R14: 431bde82d7b634db R15: 00007f64a169903b INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.805 msecs