INFO: task udevd:4881 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:26264 pid: 4881 ppid: 3560 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x759/0xd60 fs/read_write.c:485 ksys_read+0x152/0x260 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: 0033:0x7f7310c73407 RSP: 002b:00007ffcd28fa570 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f7310b85880 RCX: 00007f7310c73407 RDX: 0000000000001000 RSI: 0000558d4f261a60 RDI: 0000000000000008 RBP: 00007f7310dbbff0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a R13: 00007f7310dbbea0 R14: 0000000000000000 R15: 0000558d4f235650 INFO: task kworker/u4:7:5249 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:7 state:D stack:20880 pid: 5249 ppid: 2 flags:0x00004000 Workqueue: nfc2_nci_cmd_wq nci_cmd_work Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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:1595 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 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 syz.3.111:6118 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.111 state:D stack:25232 pid: 6118 ppid: 4956 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x89e/0x9f0 net/nfc/nci/core.c:1269 virtual_ncidev_open+0x55/0xc0 drivers/nfc/virtual_ncidev.c:146 misc_open+0x31f/0x390 drivers/char/misc.c:143 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x26f5/0x2fa0 fs/namei.c:3750 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x150/0x4b0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_openat fs/open.c:1287 [inline] __se_sys_openat fs/open.c:1282 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1282 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: 0033:0x7f1ff6dea479 RSP: 002b:00007f1ff6030028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1ff7019080 RCX: 00007f1ff6dea479 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007f1ff6e7b1bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1ff7019080 R15: 00007ffd65f4b5a8 INFO: task syz.1.112:6127 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.112 state:D stack:26928 pid: 6127 ppid: 4947 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x55/0x390 drivers/char/misc.c:107 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x26f5/0x2fa0 fs/namei.c:3750 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x150/0x4b0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_openat fs/open.c:1287 [inline] __se_sys_openat fs/open.c:1282 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1282 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: 0033:0x7fb87b2c8479 RSP: 002b:00007fb87a50e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fb87b4f7080 RCX: 00007fb87b2c8479 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fb87b3591bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb87b4f7080 R15: 00007ffd398ad828 INFO: task syz.1.112:6131 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.112 state:D stack:28144 pid: 6131 ppid: 4947 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x161/0xf90 net/netlink/genetlink.c:790 netlink_rcv_skb+0x1f5/0x440 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+0x8ba/0xbe0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2072 __do_sys_sendto net/socket.c:2084 [inline] __se_sys_sendto net/socket.c:2080 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2080 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: 0033:0x7fb87b288d4e RSP: 002b:00007fb87a4cae88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fb87a4cc6c0 RCX: 00007fb87b288d4e RDX: 000000000000001c RSI: 00007fb87a4cb000 RDI: 0000000000000006 RBP: 0000000000000000 R08: 00007fb87a4caf04 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 00007fb87a4caf58 R14: 00007fb87a4cb000 R15: 0000000000000000 INFO: task syz.4.113:6128 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.113 state:D stack:26672 pid: 6128 ppid: 4960 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x55/0x390 drivers/char/misc.c:107 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x26f5/0x2fa0 fs/namei.c:3750 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x150/0x4b0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_openat fs/open.c:1287 [inline] __se_sys_openat fs/open.c:1282 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1282 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: 0033:0x7fdaee13a479 RSP: 002b:00007fdaed380028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fdaee369080 RCX: 00007fdaee13a479 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fdaee1cb1bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdaee369080 R15: 00007ffed78dcf18 INFO: task syz.4.113:6130 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.113 state:D stack:26608 pid: 6130 ppid: 4960 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x970/0xd70 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+0xcea/0xf90 net/netlink/genetlink.c:792 netlink_rcv_skb+0x1f5/0x440 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+0x8ba/0xbe0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499 __sys_sendmsg net/socket.c:2528 [inline] __do_sys_sendmsg net/socket.c:2537 [inline] __se_sys_sendmsg+0x1af/0x290 net/socket.c:2535 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: 0033:0x7fdaee13a479 RSP: 002b:00007fdaed35f028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fdaee369160 RCX: 00007fdaee13a479 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000007 RBP: 00007fdaee1cb1bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdaee369160 R15: 00007ffed78dcf18 INFO: task syz.0.114:6135 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.114 state:D stack:26672 pid: 6135 ppid: 4945 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x55/0x390 drivers/char/misc.c:107 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x26f5/0x2fa0 fs/namei.c:3750 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x150/0x4b0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_openat fs/open.c:1287 [inline] __se_sys_openat fs/open.c:1282 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1282 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: 0033:0x7f0b529e0479 RSP: 002b:00007f0b51c26028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f0b52c0f080 RCX: 00007f0b529e0479 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007f0b52a711bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0b52c0f080 R15: 00007fff1cf2ba18 INFO: task syz.0.114:6137 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.114 state:D stack:26480 pid: 6137 ppid: 4945 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x161/0xf90 net/netlink/genetlink.c:790 netlink_rcv_skb+0x1f5/0x440 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+0x8ba/0xbe0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2072 __do_sys_sendto net/socket.c:2084 [inline] __se_sys_sendto net/socket.c:2080 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2080 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: 0033:0x7f0b529a0d4e RSP: 002b:00007f0b51c03e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f0b51c056c0 RCX: 00007f0b529a0d4e RDX: 000000000000001c RSI: 00007f0b51c04000 RDI: 0000000000000008 RBP: 0000000000000000 R08: 00007f0b51c03f04 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008 R13: 00007f0b51c03f58 R14: 00007f0b51c04000 R15: 0000000000000000 INFO: task syz.2.115:6138 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.115 state:D stack:26896 pid: 6138 ppid: 4948 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 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+0xcfc/0x2400 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+0x55/0x390 drivers/char/misc.c:107 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x26f5/0x2fa0 fs/namei.c:3750 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x150/0x4b0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_openat fs/open.c:1287 [inline] __se_sys_openat fs/open.c:1282 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1282 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: 0033:0x7f8d43117479 RSP: 002b:00007f8d4235d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f8d43346080 RCX: 00007f8d43117479 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007f8d431a81bc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8d43346080 R15: 00007ffdf7535768 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3951: #0: ffff88814cae7098 (&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+0x5df/0x1a70 drivers/tty/n_tty.c:2158 4 locks held by udevd/4881: #0: ffff88802c228d58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182 #1: ffff88805c728c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112 #2: ffff88805b3731d8 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x71/0x3c0 fs/kernfs/file.c:113 #3: ffff88807d9a5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #3: ffff88807d9a5190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17a/0x330 drivers/base/core.c:2408 2 locks held by kworker/u4:6/5000: #0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa5/0x140 kernel/sched/core.c:483 #1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x499/0x7d0 kernel/sched/psi.c:882 3 locks held by kworker/u4:7/5249: #0: ffff88807890b138 ((wq_completion)nfc2_nci_cmd_wq){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc9000122fd00 ((work_completion)(&ndev->cmd_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8cb52d68 (nci_mutex){+.+.}-{3:3}, at: virtual_nci_send+0x1d/0xd0 drivers/nfc/virtual_ncidev.c:54 3 locks held by syz.3.111/6118: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 #1: ffffffff8cb52d68 (nci_mutex){+.+.}-{3:3}, at: virtual_ncidev_open+0x15/0xc0 drivers/nfc/virtual_ncidev.c:133 #2: ffff88807d9a5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #2: ffff88807d9a5190 (&dev->mutex){....}-{3:3}, at: nfc_register_device+0x9d/0x310 net/nfc/core.c:1128 1 lock held by syz.1.112/6127: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 2 locks held by syz.1.112/6131: #0: ffffffff8d4994f0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x161/0xf90 net/netlink/genetlink.c:790 1 lock held by syz.4.113/6128: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 5 locks held by syz.4.113/6130: #0: ffffffff8d4994f0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x161/0xf90 net/netlink/genetlink.c:790 #2: ffff88807d9a5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline] #2: ffff88807d9a5190 (&dev->mutex){....}-{3:3}, at: nfc_dev_up+0x3b/0x310 net/nfc/core.c:95 #3: ffff88807d9a3350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_open_device net/nfc/nci/core.c:477 [inline] #3: ffff88807d9a3350 (&ndev->req_lock){+.+.}-{3:3}, at: nci_dev_up+0xa0/0xd70 net/nfc/nci/core.c:631 #4: ffffffff8cb52d68 (nci_mutex){+.+.}-{3:3}, at: virtual_nci_close+0x13/0x40 drivers/nfc/virtual_ncidev.c:44 1 lock held by syz.0.114/6135: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 2 locks held by syz.0.114/6137: #0: ffffffff8d4994f0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x161/0xf90 net/netlink/genetlink.c:790 1 lock held by syz.2.115/6138: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 2 locks held by syz.2.115/6140: #0: ffffffff8d4994f0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d499348 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x161/0xf90 net/netlink/genetlink.c:790 1 lock held by syz-executor/6145: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6147: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6149: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6150: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6151: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6162: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6163: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6164: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6166: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6167: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6177: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6179: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6181: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6182: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 1 lock held by syz-executor/6183: #0: ffffffff8ca078e8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x390 drivers/char/misc.c:107 2 locks held by dhcpcd/6187: #0: ffff888024782120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1744 [inline] #0: ffff888024782120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x35/0xda0 net/packet/af_packet.c:3212 #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845 ============================================= 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 03/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 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 CPU: 1 PID: 5000 Comm: kworker/u4:6 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: bat_events batadv_nc_worker RIP: 0010:kasan_check_range+0x1b2/0x290 mm/kasan/generic.c:-1 Code: 01 f3 49 89 df 49 8d 5f 07 4d 85 ff 49 0f 49 df 48 83 e3 f8 49 29 df 74 0e 41 80 3b 00 75 69 49 ff c3 49 ff cf 75 f2 5b 41 5c <41> 5e 41 5f 5d c3 45 84 ff 0f 85 91 00 00 00 41 f7 c7 00 ff 00 00 RSP: 0018:ffffc9000396fa20 EFLAGS: 00000256 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815d0086 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d89e368 RBP: ffffc9000396fb58 R08: ffffffff8d89e36f R09: 1ffffffff1b13c6d R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: ffffffff8c31eaa0 R13: 1ffff9200072df54 R14: 1ffffffff1b13c6d R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557c83433168 CR3: 000000007e061000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] cpumask_test_cpu include/linux/cpumask.h:344 [inline] cpu_online include/linux/cpumask.h:895 [inline] trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xb6/0x400 kernel/locking/lockdep.c:5594 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313 rcu_read_lock include/linux/rcupdate.h:740 [inline] batadv_nc_process_nc_paths+0xb2/0x350 net/batman-adv/network-coding.c:691 batadv_nc_worker+0x3e5/0x5c0 net/batman-adv/network-coding.c:732 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287