INFO: task syz.6.277:8997 blocked for more than 143 seconds.
      Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.277       state:D stack:28952 pid:8997  tgid:8962  ppid:6792   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_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
 inode_lock_nested include/linux/fs.h:902 [inline]
 do_unlinkat+0x1bf/0x560 fs/namei.c:4630
 __do_sys_unlink fs/namei.c:4689 [inline]
 __se_sys_unlink fs/namei.c:4687 [inline]
 __x64_sys_unlink+0x47/0x50 fs/namei.c:4687
 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: 0033:0x7fa44118e969
RSP: 002b:00007fa441f78038 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fa4413b6080 RCX: 00007fa44118e969
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000640
RBP: 00007fa441210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fa4413b6080 R15: 00007ffc735837f8
 </TASK>
INFO: task syz.6.277:8998 blocked for more than 144 seconds.
      Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.277       state:D stack:26744 pid:8998  tgid:8962  ppid:6792   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_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
 inode_lock_nested include/linux/fs.h:902 [inline]
 filename_create+0x1f9/0x470 fs/namei.c:4132
 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: 0033:0x7fa44118e969
RSP: 002b:00007fa441f57038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fa4413b6160 RCX: 00007fa44118e969
RDX: 0000000000000000 RSI: 0000200000000440 RDI: ffffffffffffff9c
RBP: 00007fa441210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa4413b6160 R15: 00007ffc735837f8
 </TASK>
INFO: task syz.6.277:9003 blocked for more than 144 seconds.
      Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.277       state:D stack:28712 pid:9003  tgid:8962  ppid:6792   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+0x2d2/0x400 fs/namei.c:2138
 lookup_last fs/namei.c:2636 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2660
 filename_lookup+0x212/0x570 fs/namei.c:2689
 user_path_at+0x3a/0x60 fs/namei.c:3120
 do_mount fs/namespace.c:4221 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount+0x2d3/0x410 fs/namespace.c:4412
 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: 0033:0x7fa44118e969
RSP: 002b:00007fa441f36038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fa4413b6240 RCX: 00007fa44118e969
RDX: 0000200000000000 RSI: 0000200000000080 RDI: 0000000000000000
RBP: 00007fa441210ab1 R08: 00002000000001c0 R09: 0000000000000000
R10: 0000000000010000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fa4413b6240 R15: 00007ffc735837f8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by kworker/u8:2/36:
3 locks held by kworker/1:1H/43:
 #0: ffff8880b89399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
 #1: ffff8880b8923b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987
 #2: ffff8880611de928 (semaphore->lock#3){....}-{0:0}, at: up+0x95/0x150 kernel/locking/semaphore.c:189
3 locks held by kworker/u8:4/63:
2 locks held by udevd/5189:
2 locks held by getty/5575:
 #0: ffff88814cb540a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/8704:
 #0: ffff888023aba0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff888023aba0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff888023aba0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
 #1: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774
4 locks held by syz.6.277/8963:
 #0: ffff88807da14420 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
 #1: ffff888056119fa8 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
 #1: ffff888056119fa8 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4132
 #2: ffff888065b04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
 #2: ffff888065b04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
 #2: ffff888065b04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385
 #3: ffff888065b26590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179
2 locks held by syz.6.277/8997:
 #0: ffff88807da14420 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
 #1: ffff888056119fa8 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
 #1: ffff888056119fa8 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: do_unlinkat+0x1bf/0x560 fs/namei.c:4630
2 locks held by syz.6.277/8998:
 #0: ffff88807da14420 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
 #1: ffff888056119fa8 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
 #1: ffff888056119fa8 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4132
1 lock held by syz.6.277/9003:
 #0: ffff888056119fa8 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline]
 #0: ffff888056119fa8 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833
2 locks held by bch-copygc/loop/8992:
2 locks held by syz-executor/9665:
 #0: ffff88805670a0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff88805670a0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff88805670a0e0 (&type->s_umount_key#71){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
 #1: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774
1 lock held by syz-executor/10044:
 #0: ffff8880317600e0 (&type->s_umount_key#86){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline]
 #0: ffff8880317600e0 (&type->s_umount_key#86){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
 #0: ffff8880317600e0 (&type->s_umount_key#86){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
4 locks held by dhcpcd-run-hook/11354:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
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+0x70e/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: 53 Comm: kworker/u8:3 Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0x829/0xd20 kernel/locking/lockdep.c:-1
Code: 89 ca c1 c2 04 41 29 cc 44 31 e2 44 01 f1 41 29 d6 89 d6 c1 c6 06 44 31 f6 01 ca 89 f0 c1 c0 08 29 f1 31 c8 01 d6 29 c2 89 c1 <c1> c1 10 31 d1 01 f0 41 89 cd 41 c1 c5 13 29 ce 41 31 f5 01 c1 44
RSP: 0018:ffffc90000be79a0 EFLAGS: 00000092
RAX: 000000000a168bd8 RBX: 0000000000000002 RCX: 000000000a168bd8
RDX: 00000000b4f25ece RSI: 00000000964ddcd2 RDI: ffff888021ec8000
RBP: ffff888021ec8af0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8b1d0b92 R12: 000000005346a101
R13: 0000000000000000 R14: 00000000e090a8ca R15: ffff888021ec8b40
FS:  0000000000000000(0000) GS:ffff8881261ff000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fee1c054378 CR3: 000000003317e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/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>