INFO: task kworker/u4:3:404 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:3 state:D stack:24328 pid: 404 ppid: 2 flags:0x00004000 Workqueue: nfc2_nci_cmd_wq nci_cmd_work Call Trace: 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 virtual_nci_send+0x1d/0xd0 drivers/nfc/virtual_ncidev.c:54 nci_cmd_work+0xa6/0x2b0 net/nfc/nci/core.c:1593 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 INFO: task udevd:3562 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:25576 pid: 3562 ppid: 1 flags:0x00004002 Call Trace: 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 device_lock include/linux/device.h:764 [inline] uevent_show+0x17a/0x330 drivers/base/core.c:2408 dev_attr_show+0x50/0xb0 drivers/base/core.c:2110 sysfs_kf_seq_show+0x316/0x4c0 fs/sysfs/file.c:61 seq_read_iter+0x49b/0xd50 fs/seq_file.c:230 call_read_iter include/linux/fs.h:2167 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0x725/0xcf0 fs/read_write.c:485 ksys_read+0x14d/0x250 fs/read_write.c:623 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: 0033:0x7f41fda81407 RSP: 002b:00007ffd9accb970 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f41fd993880 RCX: 00007f41fda81407 RDX: 0000000000001000 RSI: 000055b8c92bc550 RDI: 000000000000000c RBP: 00007f41fdbc9ff0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a R13: 00007f41fdbc9ea0 R14: 0000000000000000 R15: 000055b8c92ae7a0 INFO: task syz.1.28:5614 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.28 state:D stack:26880 pid: 5614 ppid: 5011 flags:0x00004004 Call Trace: 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 misc_open+0x56/0x360 drivers/char/misc.c:107 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x2682/0x2f30 fs/namei.c:3750 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 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: 0033:0x7f1c3d80eda9 RSP: 002b:00007f1c3ca5f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1c3da28080 RCX: 00007f1c3d80eda9 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007f1c3d8902a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1c3da28080 R15: 00007ffc77cbcb78 INFO: task syz.1.28:5621 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.28 state:D stack:26624 pid: 5621 ppid: 5011 flags:0x00004004 Call Trace: 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 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x423/0x580 net/socket.c:2073 __do_sys_sendto net/socket.c:2085 [inline] __se_sys_sendto net/socket.c:2081 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2081 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: 0033:0x7f1c3d810c3c RSP: 002b:00007f1c3ca3cec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f1c3ca3cfc0 RCX: 00007f1c3d810c3c RDX: 000000000000001c RSI: 00007f1c3ca3d010 RDI: 0000000000000008 RBP: 0000000000000000 R08: 00007f1c3ca3cf14 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000008 R13: 00007f1c3ca3cf68 R14: 00007f1c3ca3d010 R15: 0000000000000000 INFO: task syz.0.29:5611 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.29 state:D stack:26224 pid: 5611 ppid: 5006 flags:0x00004004 Call Trace: 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 device_lock include/linux/device.h:764 [inline] nfc_register_device+0x9d/0x310 net/nfc/core.c:1128 nci_register_device+0x87c/0x9c0 net/nfc/nci/core.c:1269 virtual_ncidev_open+0x55/0xc0 drivers/nfc/virtual_ncidev.c:150 misc_open+0x2f2/0x360 drivers/char/misc.c:141 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x2682/0x2f30 fs/namei.c:3750 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 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: 0033:0x7fc1a690ada9 RSP: 002b:00007fc1a5b5b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fc1a6b24080 RCX: 00007fc1a690ada9 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fc1a698c2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc1a6b24080 R15: 00007ffd4077a288 INFO: task syz.0.29:5618 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.29 state:D stack:25384 pid: 5618 ppid: 5006 flags:0x00004004 Call Trace: 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 virtual_nci_close+0x13/0x40 drivers/nfc/virtual_ncidev.c:44 nci_open_device net/nfc/nci/core.c:544 [inline] nci_dev_up+0x94d/0xd20 net/nfc/nci/core.c:631 nfc_dev_up+0x165/0x310 net/nfc/core.c:118 nfc_genl_dev_up+0x85/0xd0 net/nfc/netlink.c:770 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline] genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0xbc6/0xf40 net/netlink/genetlink.c:792 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2446 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2500 __sys_sendmsg net/socket.c:2529 [inline] __do_sys_sendmsg net/socket.c:2538 [inline] __se_sys_sendmsg+0x190/0x250 net/socket.c:2536 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: 0033:0x7fc1a690ada9 RSP: 002b:00007fc1a5b3a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fc1a6b24160 RCX: 00007fc1a690ada9 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000007 RBP: 00007fc1a698c2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc1a6b24160 R15: 00007ffd4077a288 INFO: task syz.3.30:5615 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.30 state:D stack:26592 pid: 5615 ppid: 5015 flags:0x00004004 Call Trace: 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 misc_open+0x56/0x360 drivers/char/misc.c:107 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x2682/0x2f30 fs/namei.c:3750 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 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: 0033:0x7f0138b3dda9 RSP: 002b:00007f0137d8e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f0138d57080 RCX: 00007f0138b3dda9 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007f0138bbf2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0138d57080 R15: 00007fff37e8c988 INFO: task syz.3.30:5622 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.30 state:D stack:26400 pid: 5622 ppid: 5015 flags:0x00004004 Call Trace: 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 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x423/0x580 net/socket.c:2073 __do_sys_sendto net/socket.c:2085 [inline] __se_sys_sendto net/socket.c:2081 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2081 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: 0033:0x7f0138b3fc3c RSP: 002b:00007f0137d6bec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f0137d6bfc0 RCX: 00007f0138b3fc3c RDX: 000000000000001c RSI: 00007f0137d6c010 RDI: 0000000000000008 RBP: 0000000000000000 R08: 00007f0137d6bf14 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000008 R13: 00007f0137d6bf68 R14: 00007f0137d6c010 R15: 0000000000000000 INFO: task syz.2.31:5627 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.31 state:D stack:27872 pid: 5627 ppid: 5012 flags:0x00004004 Call Trace: 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 misc_open+0x56/0x360 drivers/char/misc.c:107 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x2682/0x2f30 fs/namei.c:3750 do_filp_open+0x1b3/0x3e0 fs/namei.c:3777 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 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: 0033:0x7f4751644da9 RSP: 002b:00007f4750895038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f475185e080 RCX: 00007f4751644da9 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007f47516c62a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f475185e080 R15: 00007ffe7b72fa18 INFO: task syz.2.31:5630 blocked for more than 146 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.31 state:D stack:26624 pid: 5630 ppid: 5012 flags:0x00004004 Call Trace: 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 genl_lock net/netlink/genetlink.c:33 [inline] genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2507 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x774/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x423/0x580 net/socket.c:2073 __do_sys_sendto net/socket.c:2085 [inline] __se_sys_sendto net/socket.c:2081 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2081 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: 0033:0x7f4751646c3c RSP: 002b:00007f4750872ec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f4750872fc0 RCX: 00007f4751646c3c RDX: 000000000000001c RSI: 00007f4750873010 RDI: 0000000000000008 RBP: 0000000000000000 R08: 00007f4750872f14 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000008 R13: 00007f4750872f68 R14: 00007f4750873010 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:3/404: #0: ffff88805dfef138 ((wq_completion)nfc2_nci_cmd_wq){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90002d2fd00 ((work_completion)(&ndev->cmd_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8c94b448 (nci_mutex){+.+.}-{3:3}, at: virtual_nci_send+0x1d/0xd0 drivers/nfc/virtual_ncidev.c:54 4 locks held by udevd/3562: #0: ffff8880232152f0 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182 #1: ffff88807770ec88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112 #2: ffff8880752a8bd0 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x71/0x3c0 fs/kernfs/file.c:113 #3: ffff88802300e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #3: ffff88802300e190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17a/0x330 drivers/base/core.c:2408 2 locks held by getty/3946: #0: ffff88814c479098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 1 lock held by syz.1.28/5614: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 2 locks held by syz.1.28/5621: #0: ffffffff8d295710 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 3 locks held by syz.0.29/5611: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 #1: ffffffff8c94b448 (nci_mutex){+.+.}-{3:3}, at: virtual_ncidev_open+0x15/0xc0 drivers/nfc/virtual_ncidev.c:137 #2: ffff88802300e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #2: ffff88802300e190 (&dev->mutex){....}-{3:3}, at: nfc_register_device+0x9d/0x310 net/nfc/core.c:1128 5 locks held by syz.0.29/5618: #0: ffffffff8d295710 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 #2: ffff88802300e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #2: ffff88802300e190 (&dev->mutex){....}-{3:3}, at: nfc_dev_up+0x3b/0x310 net/nfc/core.c:95 #3: ffff888027778350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_open_device net/nfc/nci/core.c:477 [inline] #3: ffff888027778350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_dev_up+0xa0/0xd20 net/nfc/nci/core.c:631 #4: ffffffff8c94b448 (nci_mutex){+.+.}-{3:3}, at: virtual_nci_close+0x13/0x40 drivers/nfc/virtual_ncidev.c:44 1 lock held by syz.3.30/5615: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 2 locks held by syz.3.30/5622: #0: ffffffff8d295710 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 1 lock held by syz.2.31/5627: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 2 locks held by syz.2.31/5630: #0: ffffffff8d295710 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 1 lock held by syz.4.32/5631: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 2 locks held by syz.4.32/5635: #0: ffffffff8d295710 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d295568 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x137/0xf40 net/netlink/genetlink.c:790 1 lock held by syz-executor/5800: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5804: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5806: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5807: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5808: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5817: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5820: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5821: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5823: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5824: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5834: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5836: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5838: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5839: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 1 lock held by syz-executor/5840: #0: ffffffff8c804ec8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x56/0x360 drivers/char/misc.c:107 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: 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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729