syzbot

INFO: task kworker/u8:4:63 blocked for more than 143 seconds.
      Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4    state:D stack:19896 pid:63    tgid:63    ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764
 __schedule_loop kernel/sched/core.c:6841 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6856
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913
 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
 __down_write_common kernel/locking/rwsem.c:1304 [inline]
 __down_write kernel/locking/rwsem.c:1313 [inline]
 down_write+0x1d7/0x220 kernel/locking/rwsem.c:1578
 f2fs_down_write fs/f2fs/f2fs.h:2191 [inline]
 f2fs_balance_fs+0x5a9/0x810 fs/f2fs/segment.c:454
 f2fs_write_inode+0x3a7/0x540 fs/f2fs/inode.c:803
 write_inode fs/fs-writeback.c:1525 [inline]
 __writeback_single_inode+0x708/0x10d0 fs/fs-writeback.c:1745
 writeback_sb_inodes+0x820/0x1360 fs/fs-writeback.c:1976
 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2047
 wb_writeback+0x427/0xb80 fs/fs-writeback.c:2158
 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
 wb_do_writeback fs/fs-writeback.c:2315 [inline]
 wb_workfn+0xb94/0x1080 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317
 worker_thread+0x870/0xd30 kernel/workqueue.c:3398
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e9387a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e9387a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e9387a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
4 locks held by kworker/u8:4/63:
 #0: ffff888142686148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
 #0: ffff888142686148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
 #1: ffffc90001547c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
 #1: ffffc90001547c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
 #2: ffff888079b060e0 (&type->s_umount_key#43){.+.+}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
 #3: ffff88807ef89350 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2191 [inline]
 #3: ffff88807ef89350 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x5a9/0x810 fs/f2fs/segment.c:454
2 locks held by getty/5584:
 #0: ffff888031aef0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
6 locks held by syz-executor395/5824:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
 watchdog+0x1058/0x10a0 kernel/hung_task.c:399
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5824 Comm: syz-executor395 Not tainted 6.13.0-syzkaller-09793-g69b8923f5003 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:check_preemption_disabled+0x0/0x120 lib/smp_processor_id.c:13
Code: c7 00 ac 5f 8c 48 c7 c6 40 ac 5f 8c eb 1c 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89
RSP: 0018:ffffc90000007838 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc900000078a0 RCX: ffffffff819ac474
RDX: 0000000000000000 RSI: ffffffff8c0ab420 RDI: ffffffff8c5fac60
RBP: ffffc90000007988 R08: ffffffff901a1777 R09: 1ffffffff20342ee
R10: dffffc0000000000 R11: fffffbfff20342ef R12: 1ffff92000000f10
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000046
FS:  000055556997f380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fde119eb6c0 CR3: 0000000079bf2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lockdep_recursion_inc kernel/locking/lockdep.c:464 [inline]
 lock_acquire+0x1b0/0x550 kernel/locking/lockdep.c:5850
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
 __debug_check_no_obj_freed lib/debugobjects.c:1088 [inline]
 debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1129
 slab_free_hook mm/slub.c:2284 [inline]
 slab_free_after_rcu_debug+0xbf/0x280 mm/slub.c:4659
 rcu_do_batch kernel/rcu/tree.c:2546 [inline]
 rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2802
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:88 [inline]
RIP: 0010:do_raw_spin_lock+0x106/0x370 kernel/locking/spinlock_debug.c:115
Code: 49 8d 5c 24 08 49 89 df 49 c1 ef 03 41 0f b6 04 17 84 c0 0f 85 b3 01 00 00 4c 89 6c 24 30 4c 8d 74 24 60 48 89 5c 24 18 8b 03 <65> 8b 0d 9f a6 67 7e 39 c8 0f 84 21 01 00 00 4d 89 f5 49 c1 ed 03
RSP: 0018:ffffc90003eee460 EFLAGS: 00000246
RAX: 00000000ffffffff RBX: ffff88807ef88d40 RCX: ffff88803392da00
RDX: dffffc0000000000 RSI: 1ffff920007ddc94 RDI: ffff88807ef88d38
RBP: ffffc90003eee538 R08: ffffffff942c3927 R09: 1ffffffff2858724
R10: dffffc0000000000 R11: fffffbfff2858725 R12: ffff88807ef88d38
R13: ffff88807ef88d48 R14: ffffc90003eee4c0 R15: 1ffff1100fdf11a8
 spin_lock include/linux/spinlock.h:351 [inline]
 __lookup_extent_tree+0x4ce/0xd10 fs/f2fs/extent_cache.c:520
 f2fs_lookup_read_extent_cache_block+0xa7/0x1c0 fs/f2fs/extent_cache.c:1047
 f2fs_get_read_data_page+0x104/0xb30 fs/f2fs/data.c:1209
 gc_data_segment fs/f2fs/gc.c:1638 [inline]
 do_garbage_collect+0x3f55/0x80e0 fs/f2fs/gc.c:1825
 f2fs_gc+0xf3a/0x2f60 fs/f2fs/gc.c:1929
 f2fs_balance_fs+0x5f1/0x810 fs/f2fs/segment.c:456
 f2fs_map_blocks+0x444c/0x4e80 fs/f2fs/data.c:1779
 f2fs_expand_inode_data+0x6db/0xca0 fs/f2fs/file.c:1856
 f2fs_fallocate+0x537/0xa10 fs/f2fs/file.c:1959
 vfs_fallocate+0x623/0x7a0 fs/open.c:338
 do_vfs_ioctl+0x258c/0x2e40 fs/ioctl.c:885
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0x80/0x170 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7bc9e33249
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:00007ffebb2720d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7bc9e7c12f RCX: 00007f7bc9e33249
RDX: 00000000200000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00000000000016be R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffebb272120
R13: 00007ffebb272200 R14: 431bde82d7b634db R15: 00007f7bc9e7c01d
 </TASK>