INFO: task syz.2.7:5859 blocked for more than 157 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.7 state:D stack:28008 pid:5859 ppid:5776 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747 __fdget_pos+0x2a3/0x330 fs/file.c:1040 fdget_pos include/linux/file.h:75 [inline] ksys_write+0x7b/0x260 fs/read_write.c:628 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f66d7b9de99 RSP: 002b:00007f66d8a76028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f66d7e26090 RCX: 00007f66d7b9de99 RDX: 0000000000000002 RSI: 0000200000000300 RDI: 0000000000000004 RBP: 00007f66d7c33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f66d7e26128 R14: 00007f66d7e26090 R15: 00007ffd9bdf6038 INFO: task syz.2.7:5862 blocked for more than 158 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.7 state:D stack:28104 pid:5862 ppid:5776 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747 __fdget_pos+0x2a3/0x330 fs/file.c:1040 fdget_pos include/linux/file.h:75 [inline] ksys_write+0x7b/0x260 fs/read_write.c:628 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f66d7b9de99 RSP: 002b:00007f66d8a55028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f66d7e26180 RCX: 00007f66d7b9de99 RDX: 0000000000000002 RSI: 0000200000000300 RDI: 0000000000000004 RBP: 00007f66d7c33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f66d7e26218 R14: 00007f66d7e26180 R15: 00007ffd9bdf6038 INFO: task syz.3.17:5904 blocked for more than 158 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.17 state:D stack:27912 pid:5904 ppid:5773 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747 write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 nfsctl_transaction_write+0x10c/0x150 fs/nfsd/nfsctl.c:113 vfs_write+0x299/0x9a0 fs/read_write.c:582 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f1fa2b9de99 RSP: 002b:00007f1fa3b02028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1fa2e25fa0 RCX: 00007f1fa2b9de99 RDX: 0000000000000009 RSI: 0000200000000140 RDI: 0000000000000003 RBP: 00007f1fa2c33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1fa2e26038 R14: 00007f1fa2e25fa0 R15: 00007ffd452c5408 INFO: task syz.3.17:5905 blocked for more than 159 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.17 state:D stack:27912 pid:5905 ppid:5773 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747 nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 write_threads+0x393/0x510 fs/nfsd/nfsctl.c:417 nfsctl_transaction_write+0x10c/0x150 fs/nfsd/nfsctl.c:113 vfs_write+0x299/0x9a0 fs/read_write.c:582 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f1fa2b9de99 RSP: 002b:00007f1fa3ae1028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1fa2e26090 RCX: 00007f1fa2b9de99 RDX: 0000000000000002 RSI: 00002000000001c0 RDI: 0000000000000004 RBP: 00007f1fa2c33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1fa2e26128 R14: 00007f1fa2e26090 R15: 00007ffd452c5408 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/0:2/790: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #1: ffffc90003957d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc90003957d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 2 locks held by kworker/u4:7/2938: #0: ffff8881400cb538 ((wq_completion)xprtiod){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff8881400cb538 ((wq_completion)xprtiod){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 #1: ffffc9000bc17d00 ((work_completion)(&(&transport->connect_worker)->work)#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc9000bc17d00 ((work_completion)(&(&transport->connect_worker)->work)#2){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730 1 lock held by syslogd/5121: 2 locks held by getty/5530: #0: ffff88814cb3e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217 3 locks held by syz.2.7/5857: #0: ffff88802ecfcfc8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff888024310418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 1 lock held by syz.2.7/5859: #0: ffff88802ecfcfc8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 1 lock held by syz.2.7/5862: #0: ffff88802ecfcfc8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 3 locks held by syz.3.17/5904: #0: ffff88807e72b9c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88807a5a2418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.3.17/5905: #0: ffff88807ad02848 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88807a5a2418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.5.93/6297: #0: ffff88802e3d14c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff888053638418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 1 lock held by syz.5.93/6301: #0: ffff88802e3d14c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 3 locks held by syz.6.122/6422: #0: ffff88802591a848 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88807b75e418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_versions+0x96/0xe00 fs/nfsd/nfsctl.c:676 3 locks held by syz.6.122/6424: #0: ffff88807c4619c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88807b75e418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.6.122/6427: #0: ffff88802e63c0c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88807b75e418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.4.124/6442: #0: ffff888052d300c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88805fe56418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_versions+0x96/0xe00 fs/nfsd/nfsctl.c:676 3 locks held by syz.4.124/6444: #0: ffff888078d5a0c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88805fe56418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.4.124/6446: #0: ffff88807a8f8d48 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88805fe56418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.7.146/6640: #0: ffff888028a534c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88805f01a418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_versions+0x96/0xe00 fs/nfsd/nfsctl.c:676 3 locks held by syz.7.146/6642: #0: ffff88807d5f1c48 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88805f01a418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.7.146/6643: #0: ffff88802af22ac8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88805f01a418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.8.151/6687: #0: ffff888063e8f748 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff888076caa418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.3.173/7028: #0: ffff88807cf8cac8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88807adfe418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.3.173/7031: #0: ffff888028a3e0c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88807adfe418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.2.211/7045: #0: ffff8880253d1c48 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88802c3dc418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_versions+0x96/0xe00 fs/nfsd/nfsctl.c:676 3 locks held by syz.2.211/7046: #0: ffff8880242125c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88802c3dc418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.2.211/7049: #0: ffff888030b5e348 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88802c3dc418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.9.221/7081: #0: ffff88807e1d3c48 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff8880521d4418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.9.221/7086: #0: ffff88807e1d20c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff8880521d4418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.0.252/7178: #0: ffff88807ad039c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88802f55c418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.0.252/7180: #0: ffff88807de78848 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff88802f55c418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 3 locks held by syz.1.265/7361: #0: ffff888078d22ac8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff8880260c0418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.1.265/7364: #0: ffff888052e140c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff8880260c0418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 1 lock held by syz.5.267/7376: #0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 3 locks held by syz-executor/7427: #0: ffff88803cc6ce70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline] #0: ffff88803cc6ce70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709 #1: ffff88803cc6c0b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x552/0x1130 net/bluetooth/hci_sync.c:5317 #2: ffffffff8e544288 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2016 [inline] #2: ffffffff8e544288 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0x99/0x220 net/bluetooth/hci_conn.c:2571 3 locks held by syz.6.285/7538: #0: ffff88802c82a848 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff888025076418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: write_ports+0xb7/0xfa0 fs/nfsd/nfsctl.c:843 3 locks held by syz.6.285/7541: #0: ffff88802c82aac8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2a3/0x330 fs/file.c:1040 #1: ffff888025076418 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x21e/0x9a0 fs/read_write.c:580 #2: ffffffff8d3e17a8 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_svc+0x65/0xab0 fs/nfsd/nfssvc.c:788 4 locks held by syz-executor/7637: #0: ffff88803d244e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline] #0: ffff88803d244e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709 #1: ffff88803d2440b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x552/0x1130 net/bluetooth/hci_sync.c:5317 #2: ffffffff8e544288 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2016 [inline] #2: ffffffff8e544288 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0x99/0x220 net/bluetooth/hci_conn.c:2571 #3: ffff888058053338 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x7b/0x630 net/bluetooth/l2cap_core.c:1793 2 locks held by syz-executor/7659: #0: ffffffff8e3c9b10 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x342/0x5d0 net/core/net_namespace.c:516 #1: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #1: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf59/0xfa0 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7376 Comm: syz.5.267 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 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:89 [inline] RIP: 0010:check_preemption_disabled+0x56/0x110 lib/smp_processor_id.c:19 Code: 74 1f 65 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 0f 85 c4 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d c3 48 c7 04 24 00 00 00 00 9c <8f> 04 24 f7 04 24 00 02 00 00 74 cc 65 4c 8b 3d 46 cd 76 75 41 f6 RSP: 0018:ffffc9000b66f700 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88802bb58adc RCX: 0000000080000000 RDX: 0000000000000000 RSI: ffffffff8acad8c0 RDI: ffffffff8b1d0660 RBP: ffffc9000b66f850 R08: ffffffff8e8c7caf R09: 1ffffffff1d18f95 R10: dffffc0000000000 R11: fffffbfff1d18f96 R12: ffffffff81eae34c R13: dffffc0000000000 R14: ffff88802bb58000 R15: 1ffff920016cdef4 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f27efa77c50 CR3: 000000000cf32000 CR4: 00000000003506f0 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:462 [inline] lock_release+0x15c/0x8c0 kernel/locking/lockdep.c:5773 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1182 [inline] free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 vfree+0x1a7/0x340 mm/vmalloc.c:2868 kcov_put kernel/kcov.c:438 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:534 __fput+0x221/0x940 fs/file_table.c:418 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x986/0x2530 kernel/exit.c:884 do_group_exit+0x22d/0x2f0 kernel/exit.c:1026 get_signal+0x12a6/0x1390 kernel/signal.c:2903 arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f51adf9de99 Code: Unable to access opcode bytes at 0x7f51adf9de6f. RSP: 002b:00007f51ac1f6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: 0000000000000038 RBX: 00007f51ae225fa0 RCX: 00007f51adf9de99 RDX: 0000000000000000 RSI: 0000200000000300 RDI: 0000000000000004 RBP: 00007f51ae033eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f51ae226038 R14: 00007f51ae225fa0 R15: 00007ffcd7a70758