INFO: task syz.0.132:7892 blocked for more than 143 seconds.
      Not tainted 6.15.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.132       state:D stack:27080 pid:7892  tgid:7806  ppid:5819   task_flags:0x400040 flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084
 __down_read_common kernel/locking/rwsem.c:1248 [inline]
 __down_read kernel/locking/rwsem.c:1261 [inline]
 down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526
 inode_lock_shared include/linux/fs.h:877 [inline]
 lookup_slow+0x46/0x70 fs/namei.c:1833
 walk_component fs/namei.c:2138 [inline]
 link_path_walk+0x925/0xe50 fs/namei.c:2503
 path_openat+0x28c/0x3830 fs/namei.c:4035
 do_filp_open+0x1fa/0x410 fs/namei.c:4066
 do_sys_openat2+0x121/0x1c0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_openat fs/open.c:1460 [inline]
 __se_sys_openat fs/open.c:1455 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1455
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff7bd98e969
RSP: 002b:00007ff7be8c0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff7bdbb6080 RCX: 00007ff7bd98e969
RDX: 0000000000088000 RSI: 0000200000000080 RDI: 0000000000000007
RBP: 00007ff7bda10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff7bdbb6080 R15: 00007ffd2f0c09d8
 </TASK>
INFO: task syz.0.132:7895 blocked for more than 144 seconds.
      Not tainted 6.15.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.132       state:D stack:28952 pid:7895  tgid:7806  ppid:5819   task_flags:0x400040 flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084
 __down_read_common kernel/locking/rwsem.c:1248 [inline]
 __down_read kernel/locking/rwsem.c:1261 [inline]
 down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526
 inode_lock_shared include/linux/fs.h:877 [inline]
 lookup_slow+0x46/0x70 fs/namei.c:1833
 walk_component fs/namei.c:2138 [inline]
 link_path_walk+0x925/0xe50 fs/namei.c:2503
 path_parentat fs/namei.c:2707 [inline]
 __filename_parentat+0x246/0x670 fs/namei.c:2731
 filename_parentat fs/namei.c:2749 [inline]
 filename_create+0xcf/0x470 fs/namei.c:4113
 do_mkdirat+0xa0/0x590 fs/namei.c:4384
 __do_sys_mkdirat fs/namei.c:4409 [inline]
 __se_sys_mkdirat fs/namei.c:4407 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4407
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff7bd98d1d7
RSP: 002b:00007ff7be89ee68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007ff7be89eef0 RCX: 00007ff7bd98d1d7
RDX: 00000000000001ff RSI: 00002000000008c0 RDI: 00000000ffffff9c
RBP: 0000200000000880 R08: 0000200000000a40 R09: 0000000000000000
R10: 0000200000000880 R11: 0000000000000246 R12: 00002000000008c0
R13: 00007ff7be89eeb0 R14: 0000000000000000 R15: 0000200000000bc0
 </TASK>
INFO: task syz.0.132:7896 blocked for more than 145 seconds.
      Not tainted 6.15.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.132       state:D stack:28808 pid:7896  tgid:7806  ppid:5819   task_flags:0x400040 flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
 __down_write_common kernel/locking/rwsem.c:1304 [inline]
 __down_write kernel/locking/rwsem.c:1313 [inline]
 down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578
 inode_lock include/linux/fs.h:867 [inline]
 open_last_lookups fs/namei.c:3797 [inline]
 path_openat+0x8da/0x3830 fs/namei.c:4036
 do_filp_open+0x1fa/0x410 fs/namei.c:4066
 do_sys_openat2+0x121/0x1c0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_open fs/open.c:1452 [inline]
 __se_sys_open fs/open.c:1448 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1448
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff7bd98e969
RSP: 002b:00007ff7be87e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ff7bdbb6240 RCX: 00007ff7bd98e969
RDX: 0000000000000000 RSI: 000000000014927e RDI: 0000200000000180
RBP: 00007ff7bda10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007ff7bdbb6240 R15: 00007ffd2f0c09d8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
3 locks held by kworker/u8:6/1140:
1 lock held by udevd/5189:
2 locks held by getty/5581:
 #0: ffff888030e3d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900036cb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/5871:
3 locks held by kworker/1:4/5889:
 #0: ffff8880b89399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
 #1: ffffc9000a6c7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000a6c7c60 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
 #2: ffff888027d88240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
5 locks held by syz.0.132/7807:
 #0: ffff88805dafe420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
 #1: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #1: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
 #1: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
 #2: ffff88805cbf1bf8 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:569
 #3: ffff888058c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
 #3: ffff888058c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
 #3: ffff888058c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3391
 #4: ffff888058c26590 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179
1 lock held by syz.0.132/7892:
 #0: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline]
 #0: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833
1 lock held by syz.0.132/7895:
 #0: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline]
 #0: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833
2 locks held by syz.0.132/7896:
 #0: ffff88805dafe420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
 #1: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
 #1: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
 #1: ffff88805cbf1810 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
1 lock held by bch-copygc/loop/7885:
1 lock held by dhcpcd/12249:
 #0: ffff8880528f0258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
 #0: ffff8880528f0258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252
2 locks held by dhcpcd/12250:
 #0: ffff88805ee6c258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
 #0: ffff88805ee6c258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252
 #1: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 #1: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
1 lock held by dhcpcd/12251:
 #0: ffff88807923e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
 #0: ffff88807923e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-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:274 [inline]
 watchdog+0xfee/0x1030 kernel/hung_task.c:437
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 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: 7885 Comm: bch-copygc/loop Not tainted 6.15.0-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d 7c e3 d5 0b 48 89 de 5b e9 33 40 55 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 a0 72 92 65 8b 15 38 af
RSP: 0018:ffffc9000a9c6f58 EFLAGS: 00000202
RAX: ffffffff8446721a RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff8880274d9e00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000a9c7028 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52001538df8 R12: 0000000000000001
R13: 1ffff92001538df4 R14: 0000000000000001 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881261f6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8d5927d368 CR3: 000000002f97e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 six_set_owner fs/bcachefs/six.c:87 [inline]
 __do_six_trylock+0x6b2/0x7b0 fs/bcachefs/six.c:204
 do_six_trylock fs/bcachefs/six.c:282 [inline]
 six_trylock_ip+0x2f/0xd0 fs/bcachefs/six.c:299
 six_trylock_type fs/bcachefs/six.h:209 [inline]
 btree_node_lock fs/bcachefs/btree_locking.h:291 [inline]
 btree_path_traverse_cached_fast fs/bcachefs/btree_key_cache.c:362 [inline]
 bch2_btree_path_traverse_cached+0x304/0x10d0 fs/bcachefs/btree_key_cache.c:388
 bch2_btree_path_traverse_one+0x403/0x2430 fs/bcachefs/btree_iter.c:1165
 bch2_btree_path_traverse fs/bcachefs/btree_iter.h:248 [inline]
 bch2_btree_iter_peek_slot+0x760/0x1ec0 fs/bcachefs/btree_iter.c:2769
 __bch2_bkey_get_iter fs/bcachefs/btree_iter.h:591 [inline]
 bch2_bkey_get_iter fs/bcachefs/btree_iter.h:605 [inline]
 bch2_bucket_is_movable fs/bcachefs/movinggc.c:82 [inline]
 bch2_copygc_get_buckets fs/bcachefs/movinggc.c:169 [inline]
 bch2_copygc+0x9e4/0x3cf0 fs/bcachefs/movinggc.c:221
 bch2_copygc_thread+0x8c9/0xd40 fs/bcachefs/movinggc.c:405
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>