INFO: task kworker/u8:6:1155 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-next-20250814-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:6    state:D stack:21128 pid:1155  tgid:1155  ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
 f2fs_down_write fs/f2fs/f2fs.h:2234 [inline]
 f2fs_balance_fs+0x5ab/0x7f0 fs/f2fs/segment.c:464
 f2fs_write_inode+0x3fb/0x5f0 fs/f2fs/inode.c:820
 write_inode fs/fs-writeback.c:1525 [inline]
 __writeback_single_inode+0x6f1/0xff0 fs/fs-writeback.c:1745
 writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:1976
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
 wb_writeback+0x44f/0xaf0 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+0xaef/0xef0 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5868 Comm: syz-executor394 Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:stack_trace_consume_entry+0x0/0x280 kernel/stacktrace.c:83
Code: 75 0e 48 8d 65 f0 5b 41 5e 5d c3 cc cc cc cc cc e8 65 6f cf 09 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 18 48 ba 00 00
RSP: 0018:ffffc9000424e400 EFLAGS: 00000282
RAX: ffffffff84114af7 RBX: ffffc9000424e4c0 RCX: 52ebcf89b8c01b00
RDX: ffffc9000424e401 RSI: ffffffff84114af7 RDI: ffffc9000424e4c0
RBP: ffffc9000424e490 R08: ffffc9000424f330 R09: 0000000000000000
R10: ffffc9000424e458 R11: ffffffff81ac38c0 R12: ffff88802e031e00
R13: ffff88806ff0fa00 R14: ffffffff81ac38c0 R15: ffffc9000424e408
FS:  000055557054f380(0000) GS:ffff888125c0f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056436d90c168 CR3: 0000000070b14000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_stack_walk+0x10d/0x150 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236
 mempool_alloc_noprof+0x1a7/0x510 mm/mempool.c:406
 bio_alloc_bioset+0x241/0x1110 block/bio.c:555
 f2fs_grab_read_bio+0x246/0x640 fs/f2fs/data.c:1050
 f2fs_submit_page_read+0xad/0x190 fs/f2fs/data.c:1093
 f2fs_get_read_data_folio+0x4a4/0x7d0 fs/f2fs/data.c:1268
 gc_data_segment fs/f2fs/gc.c:1641 [inline]
 do_garbage_collect+0x3898/0x6410 fs/f2fs/gc.c:1826
 f2fs_gc+0xc87/0x2590 fs/f2fs/gc.c:1931
 f2fs_balance_fs+0x5f7/0x7f0 fs/f2fs/segment.c:466
 f2fs_map_blocks+0x345f/0x4130 fs/f2fs/data.c:1792
 f2fs_expand_inode_data+0x5af/0xa60 fs/f2fs/file.c:1923
 f2fs_fallocate+0x4f5/0x990 fs/f2fs/file.c:2026
 vfs_fallocate+0x666/0x7e0 fs/open.c:342
 ioctl_preallocate fs/ioctl.c:290 [inline]
 file_ioctl+0x611/0x780 fs/ioctl.c:-1
 do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:577
 __do_sys_ioctl fs/ioctl.c:596 [inline]
 __se_sys_ioctl+0x82/0x170 fs/ioctl.c:584
 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: 0033:0x7f6c1cc97c19
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:00007ffce0008378 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00002000000000c0 RCX: 00007f6c1cc97c19
RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00002000000000e0 R08: 00005555705504c0 R09: 00005555705504c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000000d0
R13: 00002000000000c8 R14: 00002000000000c2 R15: 00007f6c1cce003b
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.879 msecs