INFO: task syz-executor:6533 blocked for more than 148 seconds.
      Not tainted 6.16.0-rc6-syzkaller-gaaef6f251176 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:6533  tgid:6533  ppid:6520   task_flags:0x400140 flags:0x00000018
Call trace:
 __switch_to+0x414/0x834 arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x1414/0x2a28 kernel/sched/core.c:6786
 __schedule_loop kernel/sched/core.c:6864 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6879
 wb_wait_for_completion+0x150/0x280 fs/fs-writeback.c:216
 __writeback_inodes_sb_nr+0x1b0/0x218 fs/fs-writeback.c:2747
 writeback_inodes_sb_nr fs/fs-writeback.c:2764 [inline]
 writeback_inodes_sb+0x78/0x8c fs/fs-writeback.c:2779
 sync_filesystem+0xa0/0x218 fs/sync.c:54
 generic_shutdown_super+0x70/0x2b8 fs/super.c:622
 kill_anon_super+0x4c/0x7c fs/super.c:1282
 btrfs_kill_super+0x40/0x58 fs/btrfs/super.c:2095
 deactivate_locked_super+0xc4/0x12c fs/super.c:474
 deactivate_super+0xe0/0x100 fs/super.c:507
 cleanup_mnt+0x31c/0x3ac fs/namespace.c:1417
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1424
 task_work_run+0x1dc/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 do_notify_resume+0x174/0x1f4 arch/arm64/kernel/entry-common.c:155
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:173 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:182 [inline]
 el0_svc+0xb8/0x180 arch/arm64/kernel/entry-common.c:880
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
1 lock held by kthreadd/2:
6 locks held by kworker/R-netns/8:
 #0: ffff0000c18a2148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff800097a57ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
 #2: ffff8000928bad50 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x6c0 net/core/net_namespace.c:662