syzbot


INFO: task hung in vivid_fop_release

Status: upstream: reported syz repro on 2025/10/26 00:40
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+5a6c1d4d53e3257cdb6a@syzkaller.appspotmail.com
First crash: 1d23h, last: 1d20h
Bug presence (2)
Date Name Commit Repro Result
2025/10/27 linux-5.15.y (ToT) ac56c046adf4 syz [report] lost connection to test machine
2025/10/27 upstream (ToT) dcb6fa37fd7b syz Didn't crash
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in vivid_fop_release media 1 1 2063d 2063d 0/29 auto-closed as invalid on 2020/06/02 22:11
upstream INFO: task hung in vivid_fop_release (2) media 1 1 347d 347d 0/29 auto-obsoleted due to no activity on 2025/02/12 03:48

Sample crash report:
INFO: task syz.4.21:4400 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21        state:D stack:27872 pid: 4400 ppid:  4331 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: 0033:0x7f54f3716fc9
RSP: 002b:00007f54f2d86038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007f54f396dfa0 RCX: 00007f54f3716fc9
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007f54f3799f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f54f396e038 R14: 00007f54f396dfa0 R15: 00007ffedf615f08
 </TASK>
INFO: task syz.0.17:4426 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D
 stack:27400 pid: 4426 ppid:  4320 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
 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
 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: 0033:0x7fcf5b8cefc9
RSP: 002b:00007fcf5af3e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007fcf5bb25fa0 RCX: 00007fcf5b8cefc9
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007fcf5b951f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcf5bb26038 R14: 00007fcf5bb25fa0 R15: 00007ffe13747528
 </TASK>
INFO: task syz.1.18:4428 blocked for more than 147 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18        state:D stack:27200 pid: 4428 ppid:  4317 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
 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
 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: 0033:0x7fdbd1446fc9
RSP: 002b:00007fdbd0ab6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007fdbd169dfa0 RCX: 00007fdbd1446fc9
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007fdbd14c9f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdbd169e038 R14: 00007fdbd169dfa0 R15: 00007ffce76ab868
 </TASK>
INFO: task syz.2.19:4430 blocked for more than 149 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19        state:D stack:27680 pid: 4430 ppid:  4323 flags:0x00104006
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
 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: 0033:0x7f1722c05fc9
RSP: 002b:00007f1722275038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007f1722e5cfa0 RCX: 00007f1722c05fc9
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007f1722c88f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1722e5d038 R14: 00007f1722e5cfa0 R15: 00007ffd600e45f8
 </TASK>

Showing all locks held in the system:
2 locks held by init/1:
 #0: ffff88802bad0828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88802bad0828 (&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
1 lock held by kthreadd/2:
3 locks held by kworker/u4:0/9:
 #0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90000ce7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
1 lock held by khungtaskd/27:
 #0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:1/144:
 #0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc900011afd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d22cad0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589
 #3: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x86b/0xa40 net/core/dev.c:10696
2 locks held by kworker/u4:3/155:
3 locks held by kworker/1:3/2304:
 #0: ffff888016871938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90005c9fd00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x81/0xa50 net/wireless/reg.c:2437
2 locks held by udevd/3561:
 #0: ffff88807cb90128 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807cb90128 (&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/3854:
 #0: ffff888140887410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #0: ffff888140887410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
 #0: ffff888140887410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
 #1: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: ip6mr_sk_done+0xaa/0x2b0 net/ipv6/ip6mr.c:1584
2 locks held by dhcpcd/3855:
 #0: ffff8880205bdc10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #0: ffff8880205bdc10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline]
 #0: ffff8880205bdc10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336
 #1: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: ip6mr_sk_done+0xaa/0x2b0 net/ipv6/ip6mr.c:1584
2 locks held by dhcpcd/3856:
 #0: ffff88802b19f828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88802b19f828 (&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 getty/3946:
 #0: ffff88802b8dd098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
2 locks held by dhcpcd/3987:
 #0: ffff88802a065528 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88802a065528 (&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/3988:
 #0: ffff88802a064028 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88802a064028 (&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/3992:
 #0: ffff88801e328f28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88801e328f28 (&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/3998:
 #0: ffff88801e32b928 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88801e32b928 (&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/4002:
 #0: ffff88802a062b28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88802a062b28 (&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/4003:
 #0: ffff88801e329d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88801e329d28 (&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 sshd-session/4189:
 #0: ffff88807a50c728 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807a50c728 (&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
3 locks held by kworker/1:4/4233:
 #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90002e0fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
6 locks held by kworker/u4:5/4281:
 #0: ffff888141fb0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc90002e7fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffff88807f0c40e0 (&type->s_umount_key#32){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
 #3: ffff88807f0c6bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1c0/0x2d20 fs/ext4/inode.c:2689
 #4: ffff88807f0c8990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1312/0x15a0 fs/jbd2/transaction.c:462
 #5: ffff888074a88278 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x8b2/0x1b30 fs/ext4/inode.c:666
3 locks held by kworker/0:23/4312:
 #0: ffff88802a485d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
 #1: ffffc9000310fd00 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
 #2: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4654
4 locks held by syz.3.20/4389:
2 locks held by syz.4.21/4400:
 #0: ffff8880268b0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 #1: ffff8880268b6aa8 (&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.0.17/4426:
 #0: ffff8880268b0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
1 lock held by syz.1.18/4428:
 #0: ffff8880268b0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
1 lock held by syz.2.19/4430:
 #0: ffff8880268b0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
1 lock held by syz.5.22/4472:

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/26 03:27 linux-5.15.y ac56c046adf4 c0460fcd .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in vivid_fop_release
2025/10/26 00:40 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in vivid_fop_release
* Struck through repros no longer work on HEAD.