INFO: task syz.2.631:12568 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.631       state:D stack:26272 pid:12568 tgid:12567 ppid:10647  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x16d9/0x5700 kernel/sched/core.c:7284
 __schedule_loop kernel/sched/core.c:7361 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7668
 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1670 [inline]
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
 __rt_mutex_slowlock_locked+0x1f88/0x25b0 kernel/locking/rtmutex.c:1787
 __rwbase_read_lock+0xc3/0x190 kernel/locking/rwbase_rt.c:114
 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
 __down_read kernel/locking/rwsem.c:1502 [inline]
 down_read+0x132/0x200 kernel/locking/rwsem.c:1576
 __super_lock fs/super.c:62 [inline]
 super_lock+0x2d6/0x3d0 fs/super.c:124
 __iterate_supers+0x26b/0x420 fs/super.c:979
 quota_sync_all fs/quota/quota.c:69 [inline]
 __do_sys_quotactl fs/quota/quota.c:938 [inline]
 __se_sys_quotactl+0x3a0/0x9f0 fs/quota/quota.c:917
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdacca1e159
RSP: 002b:00007fdacac76028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fdaccca5fa0 RCX: 00007fdacca1e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000102
RBP: 00007fdaccab506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdaccca6038 R14: 00007fdaccca5fa0 R15: 00007ffef9496848
 </TASK>

Showing all locks held in the system:
locks held by khungtaskd/38: 1, last CPU#0:
 #0: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e1c3cc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/u8:14/1419: 6, last CPU#0:
 #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff88801aeb0938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #1: ffffc900062e7c40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc900062e7c40 (net_cleanup_work){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc900062e7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #1: ffffc900062e7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #2: ffffffff8f5c7260 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf5/0x810 net/core/net_namespace.c:677
 #3: ffff888062ba1160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
 #3: ffff888062ba1160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline]
 #3: ffff888062ba1160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:575
 #4: ffff888042bd8310 (&devlink->lock_key#36){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:308 [inline]
 #4: ffff888042bd8310 (&devlink->lock_key#36){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline]
 #4: ffff888042bd8310 (&devlink->lock_key#36){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:575
 #5: ffff888061c89758 (&sb->s_type->i_mutex_key#8/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline]
 #5: ffff888061c89758 (&sb->s_type->i_mutex_key#8/2){+.+.}-{4:4}, at: __simple_recursive_removal+0x19a/0x520 fs/libfs.c:619
locks held by getty/5340: 2, on CPU#0:
 #0: ffff888036df90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900044c32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
locks held by kworker/u8:20/5839: 3, on CPU#0:
 #0: ffff888032bd8138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffff888032bd8138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffff888032bd8138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #0: ffff888032bd8138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #1: ffffc900056e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #1: ffffc900056e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffc900056e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
 #1: ffffc900056e7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
 #2: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
 #2: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x123/0x16e0 net/ipv6/addrconf.c:4230
locks held by syz-executor/10464: 3, last CPU#0:
 #0: ffff88803273a0e0 (&type->s_umount_key#81){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
 #0: ffff88803273a0e0 (&type->s_umount_key#81){++++}-{4:4}, at: __super_lock_excl fs/super.c:75 [inline]
 #0: ffff88803273a0e0 (&type->s_umount_key#81){++++}-{4:4}, at: deactivate_super+0xac/0xe0 fs/super.c:613
 #1: ffff88805fef8350 (&sbi->cp_global_sem_key){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2469 [inline]
 #1: ffff88805fef8350 (&sbi->cp_global_sem_key){+.+.}-{4:4}, at: f2fs_down_write_trace+0x34/0x1f0 fs/f2fs/checkpoint.c:181
 #2: ffff888061e59dd0 (&sb->s_type->i_lock_key#50){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #2: ffff888061e59dd0 (&sb->s_type->i_lock_key#50){+.+.}-{3:3}, at: writeback_single_inode+0x30/0xef0 fs/fs-writeback.c:1906
locks held by syz.2.631/12568: 1, on CPU#1:
 #0: ffff88803273a0e0 (&type->s_umount_key#81){++++}-{4:4}, at: __super_lock fs/super.c:62 [inline]
 #0: ffff88803273a0e0 (&type->s_umount_key#81){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:124
locks held by syz-executor/13710: 1, on CPU#0:
 #0: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
 #0: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219
locks held by syz-executor/13735: 7, last CPU#0:
 #0: ffff88803539a510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2753 [inline]
 #0: ffff88803539a510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
 #1: ffff88803b563478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
 #2: ffff8880293c3788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
 #2: ffff8880293c3788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
 #3: ffffffff8ee45e98 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x13c/0x6d0 drivers/net/netdevsim/bus.c:184
 #4: ffff888011df6160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
 #4: ffff888011df6160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1073
 #5: ffff88802c6f2310 (&devlink->lock_key#38){+.+.}-{4:4}, at: nsim_drv_probe+0xfb/0xbc0 drivers/net/netdevsim/dev.c:1583
 #6: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1060 [inline]
 #6: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x87f/0x1160 drivers/net/netdevsim/netdev.c:1154
locks held by syz-executor/13846: 4, on CPU#0:
 #0: ffff88803539a510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2753 [inline]
 #0: ffff88803539a510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
 #1: ffff888062a1cc78 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
 #2: ffff8880293c3698 (kn->active#51){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
 #2: ffff8880293c3698 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
 #3: ffffffff8ee45e98 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234
locks held by syz-executor/13921: 2, on CPU#0:
 #0: ffffffff8ed35228 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffffffff8ed35228 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8ed35228 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:595
 #1: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
 #1: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219
locks held by syz-executor/13942: 2, on CPU#0:
 #0: ffffffff8ed35228 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
 #0: ffffffff8ed35228 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8ed35228 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:595
 #1: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
 #1: ffffffff8f5d5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc10/0x1c30 net/core/rtnetlink.c:4219
locks held by dhcpcd-run-hook/13988: 4, last CPU#1:
 #0: ffffffff8e29f5b0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline]
 #0: ffffffff8e29f5b0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1595
 #1: ffff888035a4e2b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
 #1: ffff888035a4e2b0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x18e/0x1d80 mm/mmap.c:1716
 #2: ffff88802595c7b0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
 #2: ffff88802595c7b0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x27d/0x1d80 mm/mmap.c:1723
 #3: ffff8880b8743418 (&pcp->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #3: ffff8880b8743418 (&pcp->lock){+.+.}-{3:3}, at: __pud_alloc+0x231/0x460 mm/memory.c:6942

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

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 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
 trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x38b/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 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: 13988 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x6e/0xb0 kernel/rcu/tree.c:753
Code: 00 48 c7 c3 98 fe a6 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 35 8b 03 65 48 ff 0d a7 89 fa 10 74 11 83 e0 04 <c1> e8 02 5b 41 5e 41 5f c3 cc cc cc cc cc e8 1f cf 87 ff eb e8 48
RSP: 0018:ffffc9000496f0e0 EFLAGS: 00000002
RAX: 0000000000000004 RBX: ffff8880b8733e98 RCX: 8000000000000002
RDX: 0000000000000001 RSI: ffffffff8bcc4b60 RDI: ffffffff8bcc4b20
RBP: ffffc9000496f268 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200092de1c R12: dffffc0000000000
R13: ffffffff8b5ac2ee R14: ffffffff8db287d8 R15: dffffc0000000000
FS:  00007f684e01ec80(0000) GS:ffff888125cc4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055be0f25ecd0 CR3: 0000000050440000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 trace_lock_release include/trace/events/lock.h:68 [inline]
 lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5954
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:208 [inline]
 _raw_spin_unlock_irqrestore+0x1b/0x80 kernel/locking/spinlock.c:221
 unlock_rt_mutex_safe kernel/locking/rtmutex.c:350 [inline]
 rt_mutex_slowunlock+0x4ee/0xa30 kernel/locking/rtmutex.c:1467
 rt_spin_unlock+0x10f/0x200 kernel/locking/spinlock_rt.c:84
 spin_unlock include/linux/spinlock_rt.h:115 [inline]
 __pmd_alloc+0x41b/0x5e0 mm/memory.c:6974
 pmd_alloc include/linux/mm.h:3710 [inline]
 copy_pmd_range+0x54a8/0x58f0 mm/memory.c:1470
 copy_pud_range mm/memory.c:1527 [inline]
 copy_p4d_range mm/memory.c:1551 [inline]
 copy_page_range+0xb80/0x11d0 mm/memory.c:1637
 dup_mmap+0xf83/0x1d80 mm/mmap.c:1819
 dup_mm kernel/fork.c:1543 [inline]
 copy_mm+0x11a/0x480 kernel/fork.c:1595
 copy_process+0x1e7e/0x4400 kernel/fork.c:2310
 kernel_clone+0x2d2/0x8d0 kernel/fork.c:2769
 __do_sys_clone kernel/fork.c:2911 [inline]
 __se_sys_clone kernel/fork.c:2895 [inline]
 __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2895
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f684e1b8636
Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007fff4fd4c590 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fff4fd4c598 RCX: 00007f684e1b8636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 000055be0f259e60 R08: 0000000000000000 R09: 3c00000040001201
R10: 00007f684e01ef50 R11: 0000000000000246 R12: 000055be0f25d498
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>