INFO: task syz-executor:8151 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc1-next-20250613-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:19080 pid:8151  tgid:8151  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16f5/0x4d00 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:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
 kthread_stop+0x194/0x5f0 kernel/kthread.c:791
 bch2_copygc_stop+0x4f/0x150 fs/bcachefs/movinggc.c:438
 __bch2_fs_read_only+0x47/0x5b0 fs/bcachefs/super.c:281
 bch2_fs_read_only+0x42a/0xb00 fs/bcachefs/super.c:367
 __bch2_fs_stop+0x100/0x900 fs/bcachefs/super.c:678
 generic_shutdown_super+0x135/0x2c0 fs/super.c:643
 bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2618
 deactivate_locked_super+0xb9/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe74af8fc57
RSP: 002b:00007ffff4c62e18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fe74b010925 RCX: 00007fe74af8fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffff4c62ed0
RBP: 00007ffff4c62ed0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffff4c63f60
R13: 00007fe74b010925 R14: 0000000000050d73 R15: 00007ffff4c63fa0
 </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
2 locks held by getty/5594:
 #0: ffff88814cb6e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900036ab2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/5908:
1 lock held by udevd/5961:
2 locks held by syz-executor/8151:
 #0: ffff8880340ae0e0 (&type->s_umount_key#94){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff8880340ae0e0 (&type->s_umount_key#94){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff8880340ae0e0 (&type->s_umount_key#94){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
 #1: ffff888037680278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677
2 locks held by bch-copygc/loop/8996:
 #0: ffff888037684390 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
 #0: ffff888037684390 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
 #0: ffff888037684390 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3312
 #1: ffff8880376a6710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x542/0x1dc0 fs/bcachefs/btree_update_interior.c:1202
1 lock held by syz.1.831/11339:
 #0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967
2 locks held by syz.7.833/11343:
2 locks held by dhcpcd-run-hook/11353:
1 lock held by udevadm/11370:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc1-next-20250613-syzkaller #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+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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5908 Comm: udevd Not tainted 6.16.0-rc1-next-20250613-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_preemption_disabled+0x0/0x120 lib/smp_processor_id.c:13
Code: c7 00 ea e2 8b 48 c7 c6 40 ea e2 8b eb 1c 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 <55> 41 57 41 56 53 48 83 ec 10 65 48 8b 05 1e f8 34 07 48 89 44 24
RSP: 0018:ffffc90004fb7770 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: ffff88802fd9da00
RDX: 0000000000000000 RSI: ffffffff8d99f847 RDI: ffffffff8be2ea60
RBP: 00000000ffffffff R08: ffff88802fd9da00 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000246
R13: ffff88802fd9da00 R14: ffffffff8e13eee0 R15: ffff888031562770
FS:  00007f6133558880(0000) GS:ffff888125d41000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc2f7c24d8 CR3: 0000000077d5c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lockdep_recursion_inc kernel/locking/lockdep.c:468 [inline]
 lock_is_held_type+0x79/0x190 kernel/locking/lockdep.c:5942
 lock_is_held include/linux/lockdep.h:249 [inline]
 __might_resched+0xf5/0x610 kernel/sched/core.c:8762
 down_read+0x22/0x2e0 kernel/locking/rwsem.c:1523
 anon_vma_lock_read include/linux/rmap.h:137 [inline]
 validate_mm+0x1d4/0x4b0 mm/vma.c:676
 vms_complete_munmap_vmas+0x6aa/0x8a0 mm/vma.c:1291
 do_vmi_align_munmap+0x358/0x420 mm/vma.c:1531
 do_vmi_munmap+0x253/0x2e0 mm/vma.c:1579
 __vm_munmap+0x23b/0x3d0 mm/vma.c:3148
 __do_sys_munmap mm/mmap.c:1084 [inline]
 __se_sys_munmap mm/mmap.c:1081 [inline]
 __x64_sys_munmap+0x60/0x70 mm/mmap.c:1081
 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: 0033:0x7f6132f1e097
Code: 73 01 c3 48 8b 0d 61 2d 0d 00 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 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffc9027f2f8 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 00005642616543f0 RCX: 00007f6132f1e097
RDX: 0000564261642058 RSI: 0000000000000200 RDI: 00007f6132e1f000
RBP: 0000000000000006 R08: 000056426163ca00 R09: 0000000000000003
R10: 0000000000000040 R11: 0000000000000246 R12: 0000564261651fb0
R13: 00007f613367f39c R14: 0000000000000c00 R15: 0000000000000009
 </TASK>