INFO: task syz.7.1116:8954 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.1116      state:D stack:27296 pid: 8954 ppid:  8477 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 vivid_fop_release+0x66/0xad0 drivers/media/test-drivers/vivid/vivid-core.c:632
 v4l2_release+0x1f9/0x390 drivers/media/v4l2-core/v4l2-dev.c:456
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 get_signal+0x1222/0x12c0 kernel/signal.c:2672
 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3c33d14749
RSP: 002b:00007f3c31f7b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007f3c33f6afa0 RCX: 00007f3c33d14749
RDX: 0000200000000340 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007f3c31f7b090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f3c33f6b038 R14: 00007f3c33f6afa0 R15: 00007ffd36391f88
 </TASK>
INFO: task syz.0.1120:8971 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1120      state:D stack:24224 pid: 8971 ppid:  4186 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x61e/0x20a0 kernel/exit.c:883
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 get_signal+0x6ca/0x12c0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6d169ec749
RSP: 002b:00007f6d14c110e8 EFLAGS: 00000246
 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f6d16c43188 RCX: 00007f6d169ec749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6d16c43188
RBP: 00007f6d16c43180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6d16c43218 R14: 00007ffffa6e5e70 R15: 00007ffffa6e5f58
 </TASK>

Showing all locks held in the system:
2 locks held by init/1:
 #0: ffff88807e9b9628 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807e9b9628 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114
2 locks held by kworker/u4:0/9:
 #0: 
ffff8880b913a358
 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffffc90000ce7d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c720
 (
rcu_read_lock){....}-{1:2}
, at: rcu_lock_acquire+0x0/0x30
2 locks held by udevd/3559:
 #0: 
ffff88807d702b28
 (
&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114
2 locks held by dhcpcd/3852:
 #0: ffff88801e543228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88801e543228 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114
2 locks held by crond/3926:
2 locks held by getty/3949:
 #0: ffff88814da08098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
3 locks held by sshd-session/4169:
1 lock held by syz-executor/4182:
4 locks held by kworker/1:4/4224:
4 locks held by kworker/u4:12/5327:
 #0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90003027d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d226b10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589
 #3: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
3 locks held by syz-executor/6891:
 #0: ffff88804d906d48 (&tsk->futex_exit_mutex){+.+.}-{3:3}, at: futex_cleanup_begin kernel/futex/core.c:3893 [inline]
 #0: ffff88804d906d48 (&tsk->futex_exit_mutex){+.+.}-{3:3}, at: futex_exit_release+0x2f/0x1c0 kernel/futex/core.c:3945
 #1: ffff88807e926328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #1: ffff88807e926328 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #2: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #2: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #2: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114
2 locks held by syz-executor/6926:
 #0: ffff88807d701d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807d701d28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114
4 locks held by syz.2.1113/8941:
2 locks held by syz.7.1116/8954:
 #0: ffff888148f30448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 #1: ffff888148f36aa8 (&dev->mutex#4){+.+.}-{3:3}, at: vivid_fop_release+0x66/0xad0 drivers/media/test-drivers/vivid/vivid-core.c:632
1 lock held by syz.0.1120/8971:
 #0: ffff888148f30448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
3 locks held by syz-executor/9089:
 #0: ffff888055cfcf88 (&tsk->futex_exit_mutex){+.+.}-{3:3}, at: futex_cleanup_begin kernel/futex/core.c:3893 [inline]
 #0: ffff888055cfcf88 (&tsk->futex_exit_mutex){+.+.}-{3:3}, at: futex_exit_release+0x2f/0x1c0 kernel/futex/core.c:3945
 #1: ffff88807b14b228 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #1: ffff88807b14b228 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #2: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #2: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #2: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114
2 locks held by syz-executor/9116:
 #0: ffff888075f3df48 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:842 [inline]
 #0: ffff888075f3df48 (mapping.invalidate_lock){++++}-{3:3}, at: filemap_fault+0x84b/0x13b0 mm/filemap.c:3096
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114
2 locks held by syz-executor/9153:
 #0: ffff888020c5dc28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff888020c5dc28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #1: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
2 locks held by udevd/9257:
 #0: ffff88807e9b8f28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807e9b8f28 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4654 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 #1: ffffffff8c1dc6e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath+0x1056/0x27a0 mm/page_alloc.c:5114

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8941 Comm: syz.2.1113 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:kasan_check_range+0x0/0x290 mm/kasan/generic.c:188
Code: 48 01 c6 48 89 c7 e8 1f 4a e6 07 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 00 00 cc cc 00 00 cc cc 00 00 cc cc <b0> 01 48 85 f6 0f 84 a4 01 00 00 41 57 41 56 53 49 89 f8 49 01 f0
RSP: 0000:ffffc900037f63d8 EFLAGS: 00000246
RAX: ffffffff81a2b3f5 RBX: ffffea0008ff9c80 RCX: ffffffff81a2b409
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea0008ff9c80
RBP: ffffc900037f6750 R08: dffffc0000000000 R09: fffff940011ff391
R10: fffff940011ff391 R11: 1ffffd40011ff390 R12: ffffea0008ff9c80
R13: dffffc0000000000 R14: ffffea0008ff9c88 R15: 057ff00000002060
FS:  00007f80e1f306c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe27ed233dd CR3: 000000004d916000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 PageLRU include/linux/page-flags.h:350 [inline]
 shrink_page_list+0x4789/0x6b60 mm/vmscan.c:1800
 shrink_inactive_list mm/vmscan.c:2223 [inline]
 shrink_list mm/vmscan.c:2450 [inline]
 shrink_lruvec+0x1170/0x24a0 mm/vmscan.c:2769
 shrink_node_memcgs mm/vmscan.c:2956 [inline]
 shrink_node+0x10a7/0x2610 mm/vmscan.c:3079
 shrink_zones mm/vmscan.c:3285 [inline]
 do_try_to_free_pages+0x5da/0x15c0 mm/vmscan.c:3340
 try_to_free_pages+0x8ef/0xdc0 mm/vmscan.c:3575
 __perform_reclaim mm/page_alloc.c:4657 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:4678 [inline]
 __alloc_pages_slowpath+0x10d8/0x27a0 mm/page_alloc.c:5114
 __alloc_pages+0x332/0x470 mm/page_alloc.c:5500
 __get_free_pages+0x8/0x30 mm/page_alloc.c:5524
 kasan_populate_vmalloc_pte+0x21/0xc0 mm/kasan/shadow.c:266
 apply_to_pte_range mm/memory.c:2573 [inline]
 apply_to_pmd_range mm/memory.c:2617 [inline]
 apply_to_pud_range mm/memory.c:2653 [inline]
 apply_to_p4d_range mm/memory.c:2689 [inline]
 __apply_to_page_range+0x983/0xd10 mm/memory.c:2725
 alloc_vmap_area+0x19f7/0x1b20 mm/vmalloc.c:1572
 __get_vm_area_node+0x14f/0x2d0 mm/vmalloc.c:2430
 __vmalloc_node_range+0xef/0x8b0 mm/vmalloc.c:3027
 vmalloc_user+0x70/0x80 mm/vmalloc.c:3173
 vb2_vmalloc_alloc+0xec/0x330 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47
 __vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:233 [inline]
 __vb2_queue_alloc+0x73c/0x13a0 drivers/media/common/videobuf2/videobuf2-core.c:443
 vb2_core_create_bufs+0x420/0x8a0 drivers/media/common/videobuf2/videobuf2-core.c:950
 vb2_create_bufs+0x6cc/0xd00 drivers/media/common/videobuf2/videobuf2-v4l2.c:799
 vb2_ioctl_create_bufs+0x3f5/0x6b0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1031
 v4l_create_bufs+0x1dc/0x330 drivers/media/v4l2-core/v4l2-ioctl.c:2072
 __video_do_ioctl+0x97c/0xd90 drivers/media/v4l2-core/v4l2-ioctl.c:2976
 video_usercopy+0x93c/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:3324
 v4l2_ioctl+0x183/0x1d0 drivers/media/v4l2-core/v4l2-dev.c:364
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f80e3cc9749
Code: Unable to access opcode bytes at RIP 0x7f80e3cc971f.
RSP: 002b:00007f80e1f30038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f80e3f1ffa0 RCX: 00007f80e3cc9749
RDX: 0000200000000340 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007f80e3d4df91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f80e3f20038 R14: 00007f80e3f1ffa0 R15: 00007fff63315518
 </TASK>