syzbot

INFO: task kworker/u4:0:9 blocked for more than 143 seconds.
      Not tainted 5.15.168-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:0    state:D stack:23008 pid:    9 ppid:     2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 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
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
 #0: ffff8881445fc938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90000ce7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff888075c100e0 (&type->s_umount_key#43){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418
 #3: ffff88801f6c11b0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:528
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3331:
 #0: ffff88802951d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc9000208e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
4 locks held by syz-executor345/3584:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.168-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3584 Comm: syz-executor345 Not tainted 5.15.168-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:preempt_latency_start kernel/sched/core.c:5470 [inline]
RIP: 0010:preempt_count_add+0xac/0x180 kernel/sched/core.c:5493
Code: 4c 8b 74 24 18 4c 89 f7 e8 e1 8d 0c 00 85 c0 74 0a 45 31 f6 31 ff e8 d3 8d 0c 00 65 48 8b 1d eb f3 aa 7e 48 81 c3 e8 14 00 00 <48> 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 8e c1 72 00
RSP: 0018:ffffc90003195fe8 EFLAGS: 00000286
RAX: 0000000000000000 RBX: ffff8880232bee28 RCX: ffffffff8a3df300
RDX: dffffc0000000000 RSI: ffffffff81dab6e7 RDI: ffffffff813899ab
RBP: ffffc900031960f8 R08: 0000000000000013 R09: ffffc900031961b0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90003197ac0
R13: ffffffff816e0990 R14: ffffffff813899ab R15: dffffc0000000000
FS:  0000555565887380(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555658906f8 CR3: 000000001eb07000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 unwind_next_frame+0xbb/0x1fa0 arch/x86/kernel/unwind_orc.c:433
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/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+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: 0033:0x7f9ce1548b99
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:00007ffc04be2758 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9ce1548b99
RDX: 00000000200000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00007f9ce15c15f0 R08: 00005555658884c0 R09: 00005555658884c0
R10: 00005555658884c0 R11: 0000000000000246 R12: 00007ffc04be2780
R13: 00007ffc04be29a8 R14: 431bde82d7b634db R15: 00007f9ce159103b
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.699 msecs