syzbot

INFO: task syz.3.164:7005 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.164       state:D stack:28952 pid:7005  tgid:6998  ppid:5806   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x147b/0x4f50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1072 [inline]
 __start_dirop fs/namei.c:2873 [inline]
 start_dirop fs/namei.c:2884 [inline]
 do_unlinkat+0x1c3/0x590 fs/namei.c:5429
 __do_sys_unlink fs/namei.c:5483 [inline]
 __se_sys_unlink fs/namei.c:5481 [inline]
 __x64_sys_unlink+0x47/0x50 fs/namei.c:5481
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50f839acb9
RSP: 002b:00007f50f65d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007f50f8616090 RCX: 00007f50f839acb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000
RBP: 00007f50f8408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f50f8616128 R14: 00007f50f8616090 R15: 00007ffccb93c4f8
 </TASK>
INFO: task syz.3.164:7006 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.164       state:D stack:28952 pid:7006  tgid:6998  ppid:5806   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x147b/0x4f50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1072 [inline]
 __start_dirop fs/namei.c:2873 [inline]
 start_dirop fs/namei.c:2884 [inline]
 filename_create+0x200/0x370 fs/namei.c:4888
 do_mknodat+0x189/0x630 fs/namei.c:5035
 __do_sys_mknod fs/namei.c:5085 [inline]
 __se_sys_mknod fs/namei.c:5083 [inline]
 __x64_sys_mknod+0x8c/0xa0 fs/namei.c:5083
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50f839acb9
RSP: 002b:00007f50f65b4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 00007f50f8616180 RCX: 00007f50f839acb9
RDX: 0000000000000000 RSI: 0000000008001420 RDI: 0000200000000040
RBP: 00007f50f8408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f50f8616218 R14: 00007f50f8616180 R15: 00007ffccb93c4f8
 </TASK>
INFO: task syz.3.164:7007 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.164       state:D stack:26840 pid:7007  tgid:6998  ppid:5806   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x147b/0x4f50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1072 [inline]
 __start_dirop fs/namei.c:2873 [inline]
 start_dirop fs/namei.c:2884 [inline]
 do_rmdir+0x1c6/0x470 fs/namei.c:5293
 __do_sys_rmdir fs/namei.c:5324 [inline]
 __se_sys_rmdir fs/namei.c:5322 [inline]
 __x64_sys_rmdir+0x47/0x50 fs/namei.c:5322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50f839acb9
RSP: 002b:00007f50f6191028 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 00007f50f8616270 RCX: 00007f50f839acb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000200
RBP: 00007f50f8408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f50f8616308 R14: 00007f50f8616270 R15: 00007ffccb93c4f8
 </TASK>
INFO: task syz.3.164:7015 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.164       state:D stack:28624 pid:7015  tgid:6998  ppid:5806   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x147b/0x4f50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 inode_lock include/linux/fs.h:1027 [inline]
 open_last_lookups fs/namei.c:4546 [inline]
 path_openat+0xb65/0x3e70 fs/namei.c:4793
 do_filp_open+0x22d/0x490 fs/namei.c:4823
 do_sys_openat2+0x12f/0x220 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_creat fs/open.c:1514 [inline]
 __se_sys_creat fs/open.c:1508 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1508
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50f839acb9
RSP: 002b:00007f50f5d6e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f50f8616360 RCX: 00007f50f839acb9
RDX: 0000000000000000 RSI: 0000000000000165 RDI: 0000200000000080
RBP: 00007f50f8408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f50f86163f8 R14: 00007f50f8616360 R15: 00007ffccb93c4f8
 </TASK>
INFO: task syz.3.164:7016 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.164       state:D stack:28624 pid:7016  tgid:6998  ppid:5806   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x147b/0x4f50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 inode_lock include/linux/fs.h:1027 [inline]
 open_last_lookups fs/namei.c:4546 [inline]
 path_openat+0xb65/0x3e70 fs/namei.c:4793
 do_filp_open+0x22d/0x490 fs/namei.c:4823
 do_sys_openat2+0x12f/0x220 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50f839acb9
RSP: 002b:00007f50f594b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f50f8616450 RCX: 00007f50f839acb9
RDX: 0000000000042041 RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007f50f8408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f50f86164e8 R14: 00007f50f8616450 R15: 00007ffccb93c4f8
 </TASK>
INFO: task syz.3.164:7017 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.164       state:D stack:28952 pid:7017  tgid:6998  ppid:5806   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x147b/0x4f50 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
 __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
 rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
 inode_lock_nested include/linux/fs.h:1072 [inline]
 __start_dirop fs/namei.c:2873 [inline]
 start_dirop fs/namei.c:2884 [inline]
 filename_create+0x200/0x370 fs/namei.c:4888
 do_mkdirat+0xd2/0x4c0 fs/namei.c:5165
 __do_sys_mkdirat fs/namei.c:5195 [inline]
 __se_sys_mkdirat fs/namei.c:5193 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5193
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50f8399b97
RSP: 002b:00007f50f5527e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f50f5527ee0 RCX: 00007f50f8399b97
RDX: 00000000000001ff RSI: 0000200000000100 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000200000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000100
R13: 00007f50f5527ea0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/38:
 #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/44:
 #0: ffff888030239938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
 #0: ffff888030239938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
 #1: ffffc90000b67bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
 #1: ffffc90000b67bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
 #2: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #2: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4194
4 locks held by kworker/u8:3/58:
 #0: ffff888141693138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
 #0: ffff888141693138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
 #1: ffffc9000124fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
 #1: ffffc9000124fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
 #2: ffff8880312c60d0 (&type->s_umount_key#58){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
 #3: ffff88805d4a76e8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
3 locks held by kworker/u8:8/1163:
 #0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
 #0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
 #1: ffffc90004cafbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
 #1: ffffc90004cafbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
 #2: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
3 locks held by aoe_tx0/1323:
5 locks held by kworker/u8:14/3253:
 #0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
 #0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
 #1: ffffc9000d0f7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
 #1: ffffc9000d0f7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
 #2: ffffffff8ed29560 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670
 #3: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
 #3: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x940 net/core/net_namespace.c:248
 #4: ffffffff8d9cdfb0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3816
5 locks held by klogd/5159:
1 lock held by dhcpcd/5465:
 #0: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_deladdr+0x23d/0x370 net/ipv6/addrconf.c:4799
2 locks held by getty/5558:
 #0: ffff88803513d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/1:7/5990:
 #0: ffff88813fe15138 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
 #0: ffff88813fe15138 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
 #1: ffffc900053afbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
 #1: ffffc900053afbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
 #2: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
4 locks held by syz.3.164/6999:
2 locks held by syz.3.164/7005:
 #0: ffff8880312c6480 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: do_unlinkat+0x1c3/0x590 fs/namei.c:5429
2 locks held by syz.3.164/7006:
 #0: ffff8880312c6480 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4888
2 locks held by syz.3.164/7007:
 #0: ffff8880312c6480 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: do_rmdir+0x1c6/0x470 fs/namei.c:5293
2 locks held by syz.3.164/7015:
 #0: ffff8880312c6480 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: open_last_lookups fs/namei.c:4546 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: path_openat+0xb65/0x3e70 fs/namei.c:4793
2 locks held by syz.3.164/7016:
 #0: ffff8880312c6480 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: open_last_lookups fs/namei.c:4546 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: path_openat+0xb65/0x3e70 fs/namei.c:4793
2 locks held by syz.3.164/7017:
 #0: ffff8880312c6480 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline]
 #1: ffff88805d4a7ab8 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4888
1 lock held by syz-executor/7617:
 #0: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #0: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x65f/0xe30 net/ipv6/addrconf.c:5027
1 lock held by syz-executor/7621:
 #0: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
4 locks held by syz-executor/7662:
 #0: ffff888031b4a480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
 #0: ffff888031b4a480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:682
 #1: ffff88801e294878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
 #2: ffff888026a82d28 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff888026a82d28 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
 #3: ffffffff8e5a8e78 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x710 drivers/net/netdevsim/bus.c:184
7 locks held by syz-executor/7667:
 #0: ffff888031b4a480 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
 #0: ffff888031b4a480 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:682
 #1: ffff88805a8a0c78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
 #2: ffff888026a82e18 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff888026a82e18 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
 #3: ffffffff8e5a8e78 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234
 #4: ffff88803263c0d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #4: ffff88803263c0d8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1104 [inline]
 #4: ffff88803263c0d8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1302
 #5: ffff888030f96300 (&devlink->lock_key#14){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1777
 #6: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
 #6: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2156
2 locks held by syz-executor/7694:
 #0: ffffffff8e571648 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e571648 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8e571648 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
 #1: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #1: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
 watchdog+0xf90/0xfe0 kernel/hung_task.c:515
 kthread+0x726/0x8b0 kernel/kthread.c:463
 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5159 Comm: klogd Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:649 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1231 [inline]
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline]
RIP: 0010:lock_acquire+0x4e/0x330 kernel/locking/lockdep.c:5831
Code: 48 8b ac 24 98 00 00 00 65 48 8b 05 6c 6d 64 10 48 89 44 24 58 0f 1f 44 00 00 65 8b 05 6f 6d 64 10 83 f8 08 0f 83 83 01 00 00 <89> c0 48 0f a3 05 98 cc 89 0d 73 0d e8 81 39 09 00 84 c0 0f 84 ca
RSP: 0018:ffffc90003ae76f0 EFLAGS: 00000297
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8dafc480
RBP: ffffffff8216948c R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1e4f3ef R12: 0000000000000000
R13: ffffffff8dafc480 R14: 0000000000000000 R15: 0000000000000001
FS:  00007fdd9d003c80(0000) GS:ffff8881268fc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0f5245869d CR3: 00000000117ea000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 fs_reclaim_acquire+0x98/0x100 mm/page_alloc.c:4348
 might_alloc include/linux/sched/mm.h:317 [inline]
 slab_pre_alloc_hook mm/slub.c:4904 [inline]
 slab_alloc_node mm/slub.c:5239 [inline]
 kmem_cache_alloc_node_noprof+0x46/0x6d0 mm/slub.c:5315
 __alloc_skb+0x1d7/0x390 net/core/skbuff.c:679
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6714
 sock_alloc_send_pskb+0x884/0x9a0 net/core/sock.c:2995
 unix_dgram_sendmsg+0x44e/0x17b0 net/unix/af_unix.c:2130
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3d0/0x560 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2209
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdd9d153407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffcf94c5420 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fdd9d003c80 RCX: 00007fdd9d153407
RDX: 000000000000004f RSI: 00007ffcf94c5560 RDI: 0000000000000003
RBP: 00007ffcf94c5990 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffcf94c59a8
R13: 00007ffcf94c5560 R14: 0000000000000034 R15: 00007ffcf94c5560
 </TASK>