syzbot

INFO: task syz.8.260:8397 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc4-syzkaller-00324-g1f988d0788f5 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.260       state:D stack:24680 pid:8397  tgid:8396  ppid:7421   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148
 f2fs_issue_checkpoint+0x376/0x570 fs/f2fs/checkpoint.c:-1
 f2fs_do_shutdown+0x111/0x5c0 fs/f2fs/file.c:2412
 f2fs_ioc_shutdown fs/f2fs/file.c:2496 [inline]
 __f2fs_ioctl+0x41a8/0xb610 fs/f2fs/file.c:4606
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4b3ef8e929
RSP: 002b:00007f4b3fd37038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4b3f1b5fa0 RCX: 00007f4b3ef8e929
RDX: 0000200000000080 RSI: 000000008004587d RDI: 0000000000000005
RBP: 00007f4b3f010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4b3f1b5fa0 R15: 00007ffed1762c38
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/u8:2/36:
 #0: ffff8880212a0148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff8880212a0148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc90000ac7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90000ac7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffff888027a180e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
2 locks held by getty/5597:
 #0: ffff88814c3630a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by udevd/6026:
1 lock held by syz.8.260/8397:
 #0: ffff888027a18428 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write_file+0x60/0x200 fs/namespace.c:601
2 locks held by f2fs_ckpt-7:8/8417:
5 locks held by syz-executor/9468:
 #0: ffff8880280c60e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff8880280c60e0 (&type->s_umount_key#51){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff8880280c60e0 (&type->s_umount_key#51){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffff88803bb00278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:676
 #2: ffff88803bb04740 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x18bd/0x1a40 fs/bcachefs/btree_write_buffer.c:571
 #3: ffff88803bb04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
 #3: ffff88803bb04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
 #3: ffff88803bb04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3299
 #4: ffff88803bb26710 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211
2 locks held by kworker/u8:10/9628:
2 locks held by syz.6.399/9735:
 #0: ffff888027a180e0 (&type->s_umount_key#65){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
 #0: ffff888027a180e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
 #1: ffff8881427a87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
 #1: ffff8881427a87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
3 locks held by bch-reclaim/loo/9883:
 #0: ffff88803bb4af68 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:767
 #1: ffff88803bb04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
 #1: ffff88803bb04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
 #1: ffff88803bb04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7f4/0xd80 fs/bcachefs/btree_iter.c:3505
 #2: ffff88803bb04740 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x18bd/0x1a40 fs/bcachefs/btree_write_buffer.c:571

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00324-g1f988d0788f5 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
 watchdog+0xfee/0x1030 kernel/hung_task.c:470
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 10423 Comm: syz.9.437 Not tainted 6.16.0-rc4-syzkaller-00324-g1f988d0788f5 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__preempt_count_add kernel/rcu/tree.c:741 [inline]
RIP: 0010:rcu_is_watching+0x4/0xb0 kernel/rcu/tree.c:744
Code: 14 8e e8 cf 23 49 03 eb cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <41> 57 41 56 53 65 ff 05 e0 dd f5 10 e8 6b 1f c1 09 89 c3 83 f8 08
RSP: 0018:ffffc90000a08be0 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff81c7ea58
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fa0bef0
RBP: ffffc90000a08c90 R08: ffffffff8fa0bef7 R09: 1ffffffff1f417de
R10: dffffc0000000000 R11: fffffbfff1f417df R12: dffffc0000000000
R13: 0000000000000002 R14: 1ffff92000141180 R15: dffffc0000000000
FS:  00007efe629f66c0(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f515ec9c6c8 CR3: 0000000069452000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 trace_irq_disable+0x37/0x110 include/trace/events/preemptirq.h:36
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:117 [inline]
 _raw_spin_lock_irq+0x7d/0xf0 kernel/locking/spinlock.c:170
 __run_timer_base+0x101/0x860 kernel/time/timer.c:2383
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline]
RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449
Code: 85 32 01 00 00 e8 e1 63 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 d0 63 1f 00 eb 06 e8 c9 63 1f 00 fb 48 c7 c7 a0 30 13 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 c9 36
RSP: 0018:ffffc90004ec6200 EFLAGS: 00000287
RAX: ffffffff81a0f9b7 RBX: ffffffff81a0f874 RCX: 0000000000080000
RDX: ffffc9000c21a000 RSI: 000000000000b568 RDI: ffffffff8e1330a0
RBP: ffffc90004ec6310 R08: ffffffff8fa0bef7 R09: 1ffffffff1f417de
R10: dffffc0000000000 R11: fffffbfff1f417df R12: dffffc0000000000
R13: 1ffff920009d8c44 R14: 0000000000000200 R15: 0000000000000091
 _printk+0xcf/0x120 kernel/printk/printk.c:2475
 __xfs_printk fs/xfs/xfs_message.c:24 [inline]
 xfs_printk_level+0x18b/0x280 fs/xfs/xfs_message.c:44
 xfs_log_check_lsn+0x23a/0x350 fs/xfs/xfs_log.c:3580
 xfs_btree_agblock_verify_crc+0xf1/0x240 fs/xfs/libxfs/xfs_btree.c:465
 xfs_allocbt_read_verify+0x18/0xe0 fs/xfs/libxfs/xfs_alloc_btree.c:313
 __xfs_buf_ioend+0x33f/0x6f0 fs/xfs/xfs_buf.c:1177
 xfs_buf_iowait+0x167/0x480 fs/xfs/xfs_buf.c:1384
 _xfs_buf_read fs/xfs/xfs_buf.c:646 [inline]
 xfs_buf_read_map+0x335/0xa50 fs/xfs/xfs_buf.c:712
 xfs_trans_read_buf_map+0x1d7/0x8e0 fs/xfs/xfs_trans_buf.c:304
 xfs_trans_read_buf fs/xfs/xfs_trans.h:212 [inline]
 xfs_btree_read_buf_block+0x290/0x470 fs/xfs/libxfs/xfs_btree.c:1402
 xfs_btree_lookup_get_block+0x28d/0x500 fs/xfs/libxfs/xfs_btree.c:1907
 xfs_btree_lookup+0x4e1/0x1410 fs/xfs/libxfs/xfs_btree.c:2018
 xfs_alloc_lookup fs/xfs/libxfs/xfs_alloc.c:166 [inline]
 xfs_alloc_lookup_eq fs/xfs/libxfs/xfs_alloc.c:184 [inline]
 xfs_alloc_fixup_trees+0x21b/0xd20 fs/xfs/libxfs/xfs_alloc.c:626
 xfs_alloc_cur_finish+0xd3/0x4b0 fs/xfs/libxfs/xfs_alloc.c:1117
 xfs_alloc_ag_vextent_near+0xd1a/0x1230 fs/xfs/libxfs/xfs_alloc.c:1776
 xfs_alloc_vextent_iterate_ags+0x640/0x940 fs/xfs/libxfs/xfs_alloc.c:3764
 xfs_alloc_vextent_start_ag+0x388/0x850 fs/xfs/libxfs/xfs_alloc.c:3839
 xfs_bmap_btalloc_best_length fs/xfs/libxfs/xfs_bmap.c:3627 [inline]
 xfs_bmap_btalloc fs/xfs/libxfs/xfs_bmap.c:3672 [inline]
 xfs_bmapi_allocate+0x188e/0x2e00 fs/xfs/libxfs/xfs_bmap.c:3947
 xfs_bmapi_write+0x7df/0x1260 fs/xfs/libxfs/xfs_bmap.c:4276
 xfs_da_grow_inode_int+0x298/0x860 fs/xfs/libxfs/xfs_da_btree.c:2315
 xfs_dir2_grow_inode+0x1f4/0x680 fs/xfs/libxfs/xfs_dir2.c:628
 xfs_dir2_sf_to_block+0x347/0x1540 fs/xfs/libxfs/xfs_dir2_block.c:1129
 xfs_dir2_sf_addname+0x722/0x1b60 fs/xfs/libxfs/xfs_dir2_sf.c:418
 xfs_dir_createname+0x471/0x610 fs/xfs/libxfs/xfs_dir2.c:361
 xfs_dir_create_child+0xe1/0x480 fs/xfs/libxfs/xfs_dir2.c:859
 xfs_create+0x66f/0xad0 fs/xfs/xfs_inode.c:734
 xfs_generic_create+0x3c9/0xad0 fs/xfs/xfs_iops.c:216
 xfs_vn_mkdir+0x37/0x50 fs/xfs/xfs_iops.c:309
 vfs_mkdir+0x303/0x510 fs/namei.c:4375
 do_mkdirat+0x247/0x590 fs/namei.c:4408
 __do_sys_mkdirat fs/namei.c:4425 [inline]
 __se_sys_mkdirat fs/namei.c:4423 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4423
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efe64b8d197
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 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:00007efe629f5e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007efe629f5ef0 RCX: 00007efe64b8d197
RDX: 00000000000001ff RSI: 0000200000000400 RDI: 00000000ffffff9c
RBP: 0000200000000340 R08: 00002000000000c0 R09: 0000000000000000
R10: 0000200000000340 R11: 0000000000000246 R12: 0000200000000400
R13: 00007efe629f5eb0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>