INFO: task syz.6.1969:20060 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.1969      state:D stack:26688 pid:20060 tgid:20032 ppid:18580  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x1553/0x5240 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289
 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:1073 [inline]
 __start_dirop fs/namei.c:2929 [inline]
 start_dirop fs/namei.c:2940 [inline]
 filename_create+0x200/0x370 fs/namei.c:4928
 filename_mkdirat+0xd2/0x520 fs/namei.c:5265
 __do_sys_mkdirat fs/namei.c:5293 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5290
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b31efb687
RSP: 002b:00007f8b3012ce58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f8b3012cee0 RCX: 00007f8b31efb687
RDX: 00000000000001ff RSI: 0000200000000000 RDI: 00000000ffffff9c
RBP: 0000200000000040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000040 R11: 0000000000000246 R12: 0000200000000000
R13: 00007f8b3012cea0 R14: 0000000000000000 R15: 0000200000000140
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/38:
 #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:2/40:
 #0: ffff88801aee4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #0: ffff88801aee4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
 #1: ffffc90000b17c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
 #1: ffffc90000b17c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
 #2: ffff88803df800d0 (&type->s_umount_key#77){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
 #3: ffff888061e14fe8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
4 locks held by kworker/u8:9/1005:
 #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #0: ffff88801aee1138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
 #1: ffffc90005c17c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
 #1: ffffc90005c17c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
 #2: ffffffff8f14e800 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675
 #3: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
 #3: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x940 net/core/net_namespace.c:248
2 locks held by dhcpcd/5459:
 #0: ffff888036e9e928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xe4/0xe80 net/netlink/af_netlink.c:2267
 #1: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6848
2 locks held by getty/5551:
 #0: ffff8880376af0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by kworker/0:3/5784:
 #0: ffff888019c07938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #0: ffff888019c07938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
 #1: ffffc9000475fc40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
 #1: ffffc9000475fc40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
 #2: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
2 locks held by kworker/1:6/5882:
1 lock held by udevd/16594:
4 locks held by syz.6.1969/20033:
2 locks held by syz.6.1969/20060:
 #0: ffff88803df80480 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
 #1: ffff888061e153b8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
 #1: ffff888061e153b8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2929 [inline]
 #1: ffff888061e153b8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2940 [inline]
 #1: ffff888061e153b8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4928
3 locks held by syz-executor/20203:
2 locks held by syz.8.2004/20313:
 #0: ffff88803df800d0 (&type->s_umount_key#77){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
 #0: ffff88803df800d0 (&type->s_umount_key#77){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
 #1: ffff8880263968c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:398 [inline]
 #1: ffff8880263968c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x209/0xc30 fs/fs-writeback.c:2940
4 locks held by kworker/u8:0/20394:
 #0: ffff88801aee4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #0: ffff88801aee4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
 #1: ffffc90003fcfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
 #1: ffffc90003fcfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
 #2: ffff8880373220d0 (&type->s_umount_key#77){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
 #3: ffff8880602d59a8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
4 locks held by syz.3.2070/20919:
3 locks held by kworker/u8:13/21548:
 #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
 #0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
 #1: ffffc900045afc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
 #1: ffffc900045afc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
 #2: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
2 locks held by syz-executor/21751:
 #0: ffffffff8f6a8ec0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8f6a8ec0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8f6a8ec0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
 #1: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #1: ffffffff8f15cfb8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4093
4 locks held by syz.0.2181/21812:
3 locks held by syz.1.2179/21817:
6 locks held by syz.2.2183/21834:

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

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 03/18/2026
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+0xfd9/0x1030 kernel/hung_task.c:515
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 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: 21812 Comm: syz.0.2181 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:check_preemption_disabled+0x29/0xe0 lib/smp_processor_id.c:19
Code: 90 55 41 57 41 56 53 65 8b 05 47 73 2a 07 65 8b 0d 3c 73 2a 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d e9 99 a5 03 00 cc 9c <59> f7 c1 00 02 00 00 74 ea 65 4c 8b 3d ee 72 2a 07 41 f6 47 2f 04
RSP: 0018:ffffc900047cf0c0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000202 RCX: 0000000080000000
RDX: ffffffff8feeca00 RSI: ffffffff8d57dfea RDI: ffffffff8ba67a00
RBP: dffffc0000000000 R08: 0000000000000022 R09: ffffffff8ddcb9c0
R10: ffffc900047cf278 R11: ffffffff81af9290 R12: 00007fea3ab2dda8
R13: ffffffff81767e65 R14: ffffffff8ddcb9c0 R15: ffff88803147bd00
FS:  00007fea3ab2e6c0(0000) GS:ffff888126435000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055bb8ddff250 CR3: 0000000065ad2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
 lock_release+0xa1/0x3d0 kernel/locking/lockdep.c:5888
 rcu_lock_release include/linux/rcupdate.h:322 [inline]
 rcu_read_unlock include/linux/rcupdate.h:881 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 save_stack+0x124/0x230 mm/page_owner.c:165
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 free_unref_folios+0xe7b/0x1c70 mm/page_alloc.c:3040
 folios_put_refs+0x56f/0x680 mm/swap.c:1002
 folio_batch_release include/linux/pagevec.h:101 [inline]
 shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149
 shmem_truncate_range mm/shmem.c:1277 [inline]
 shmem_evict_inode+0x240/0x9e0 mm/shmem.c:1407
 evict+0x61e/0xb10 fs/inode.c:846
 __dentry_kill+0x1a2/0x5e0 fs/dcache.c:670
 finish_dput+0xc9/0x480 fs/dcache.c:879
 __fput+0x6a3/0xa90 fs/file_table.c:477
 fput_close_sync+0x11f/0x240 fs/file_table.c:574
 __do_sys_close fs/open.c:1509 [inline]
 __se_sys_close fs/open.c:1494 [inline]
 __x64_sys_close+0x7e/0x110 fs/open.c:1494
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fea3c89d04e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007fea3ab2dda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007fea3ab2e6c0 RCX: 00007fea3c89d04e
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000010 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fea3ab2dee0 R14: 00007fea3ab2dea0 R15: 00007fea3270e000
 </TASK>