INFO: task syz-executor:5829 blocked for more than 143 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:20800 pid:5829  tgid:5829  ppid:1      task_flags:0x40054c flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
 mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 exit_mmap+0x27b/0xb10 mm/mmap.c:1285
 __mmput+0x118/0x430 kernel/fork.c:1173
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x658/0x2310 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4beab85897
RSP: 002b:00007ffd38153180 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000000277 RCX: 00007f4beab85897
RDX: 0000000040000000 RSI: 00007ffd381531ec RDI: 00000000ffffffff
RBP: 00007ffd381531ec R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000000b3
R13: 000055555ab88590 R14: 00000000000307b4 R15: 00007ffd38153240
 </TASK>
INFO: task syz-executor:5840 blocked for more than 143 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21368 pid:5840  tgid:5840  ppid:1      task_flags:0x40054c flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
 mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 exit_mmap+0x27b/0xb10 mm/mmap.c:1285
 __mmput+0x118/0x430 kernel/fork.c:1173
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x658/0x2310 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7e1ed85897
RSP: 002b:00007ffe51e746a0 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000000280 RCX: 00007f7e1ed85897
RDX: 0000000040000000 RSI: 00007ffe51e7470c RDI: 00000000ffffffff
RBP: 00007ffe51e7470c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000000b8
R13: 0000555568ec2590 R14: 00000000000305bf R15: 00007ffe51e74760
 </TASK>
INFO: task syz.4.953:9832 blocked for more than 144 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.953       state:D stack:23776 pid:9832  tgid:9831  ppid:5842   task_flags:0x40054c flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
 mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 exit_mmap+0x27b/0xb10 mm/mmap.c:1285
 __mmput+0x118/0x430 kernel/fork.c:1173
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x658/0x2310 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f86ad58f749
RSP: 002b:00007f86ae3690e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f86ad7e5fa8 RCX: 00007f86ad58f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f86ad7e5fa8
RBP: 00007f86ad7e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f86ad7e6038 R14: 00007ffd002eee20 R15: 00007ffd002eef08
 </TASK>
INFO: task syz.2.957:9845 blocked for more than 144 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.957       state:D stack:23840 pid:9845  tgid:9843  ppid:5829   task_flags:0x40054c flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
 mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 exit_mmap+0x27b/0xb10 mm/mmap.c:1285
 __mmput+0x118/0x430 kernel/fork.c:1173
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x658/0x2310 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4beab8f749
RSP: 002b:00007f4bebaf7038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: 0000000000000150 RBX: 00007f4beade5fa0 RCX: 00007f4beab8f749
RDX: 0000000020004000 RSI: 0000200000000480 RDI: 0000000000000009
RBP: 00007f4beac13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4beade6038 R14: 00007f4beade5fa0 R15: 00007ffd38152e28
 </TASK>
INFO: task syz.3.961:9864 blocked for more than 144 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.961       state:D stack:25632 pid:9864  tgid:9864  ppid:5840   task_flags:0x40004c flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write kernel/locking/rwsem.c:1326 [inline]
 down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
 mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 exit_mmap+0x27b/0xb10 mm/mmap.c:1285
 __mmput+0x118/0x430 kernel/fork.c:1173
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x658/0x2310 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
 __do_sys_exit_group kernel/exit.c:1123 [inline]
 __se_sys_exit_group kernel/exit.c:1121 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1121
 x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7e1ed8f749
RSP: 002b:00007ffe51e746a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7e1ed8f749
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffe51e7470c R08: 0000000751e7479f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000000b8
R13: 00000000000927c0 R14: 00000000000304ef R15: 00007ffe51e74760
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
 #0: ffffffff8df41a20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5590:
 #0: ffff88814d9350a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5829:
 #0: ffff8880312aa800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 #0: ffff8880312aa800 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27b/0xb10 mm/mmap.c:1285
1 lock held by syz-executor/5840:
 #0: ffff88807e8f9bc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 #0: ffff88807e8f9bc0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27b/0xb10 mm/mmap.c:1285
2 locks held by kworker/u8:16/6799:
 #0: ffff88813ff29148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
 #0: ffff88813ff29148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
 #1: ffffc9001b377b80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
 #1: ffffc9001b377b80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
1 lock held by syz.4.953/9832:
 #0: ffff8880799f3440 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 #0: ffff8880799f3440 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27b/0xb10 mm/mmap.c:1285
1 lock held by syz.2.957/9845:
 #0: ffff8880799f2800 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 #0: ffff8880799f2800 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27b/0xb10 mm/mmap.c:1285
1 lock held by modprobe/9861:
 #0: ffff88801e794cc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:353 [inline]
 #0: ffff88801e794cc0 (&mm->mmap_lock){++++}-{4:4}, at: do_mprotect_pkey+0x20f/0xcd0 mm/mprotect.c:832
1 lock held by syz.3.961/9864:
 #0: ffff88801e797180 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:335 [inline]
 #0: ffff88801e797180 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x27b/0xb10 mm/mmap.c:1285
3 locks held by kworker/u8:20/11668:
 #0: ffff88801aa9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
 #0: ffff88801aa9f148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
 #1: ffffc9000484fb80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
 #1: ffffc9000484fb80 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
 #2: ffffffff8f304bf0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670
3 locks held by syz.7.1693/12835:
 #0: ffffffff8f304bf0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cc/0x570 net/core/net_namespace.c:577
 #1: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
 #1: ffffffff8f311c88 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x990 net/core/net_namespace.c:248
 #2: ffffffff8df47578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #2: ffffffff8df47578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:956
1 lock held by syz.0.1695/12840:
 #0: ffff888034505468 (&pipe->mutex){+.+.}-{4:4}, at: pipe_release+0x48/0x330 fs/pipe.c:729
1 lock held by syz.0.1695/12841:
 #0: ffff888034505468 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x2e/0x440 fs/splice.c:1289
1 lock held by syz.0.1695/12845:
 #0: ffff888034505468 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1460 fs/pipe.c:458

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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:160 [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+0xf95/0xfe0 kernel/hung_task.c:515
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 93 90 0c 00 f3 0f 1e fa fb f4 <e9> c8 ed 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c6
RAX: 2595e2e665173e00 RBX: ffffffff81978fda RCX: 2595e2e665173e00
RDX: 0000000000000001 RSI: ffffffff8d7925e3 RDI: ffffffff8bc08360
RBP: ffffffff8dc07ea8 R08: ffff8880b86336db R09: 1ffff110170c66db
R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f822070
R13: 1ffffffff1b92a68 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125e35000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcf5171b48 CR3: 0000000076294000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1ea/0x520 kernel/sched/idle.c:332
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
 rest_init+0x2de/0x300 init/main.c:757
 start_kernel+0x3a7/0x400 init/main.c:1206
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147
 </TASK>