============================================ WARNING: possible recursive locking detected 5.17.0-syzkaller-02172-g6b1f86f8e9c7 #0 Not tainted -------------------------------------------- syz-executor.2/4365 is trying to acquire lock: ffffffff8c6d6998 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x147/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2093 but task is already holding lock: ffffffff8c6d6998 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x147/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2093 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(qp_broker_list.mutex); lock(qp_broker_list.mutex); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by syz-executor.2/4365: #0: ffffffff8c6d6998 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x147/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2093 stack backtrace: CPU: 0 PID: 4365 Comm: syz-executor.2 Not tainted 5.17.0-syzkaller-02172-g6b1f86f8e9c7 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2958 [inline] check_deadlock kernel/locking/lockdep.c:3001 [inline] validate_chain kernel/locking/lockdep.c:3790 [inline] __lock_acquire.cold+0x12c/0x3a7 kernel/locking/lockdep.c:5029 lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 __mutex_lock_common kernel/locking/mutex.c:600 [inline] __mutex_lock+0x12f/0x12f0 kernel/locking/mutex.c:733 vmci_qp_broker_detach+0x147/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2093 ctx_free_ctx+0x4cc/0xd30 drivers/misc/vmw_vmci/vmci_context.c:444 kref_put include/linux/kref.h:65 [inline] vmci_ctx_put drivers/misc/vmw_vmci/vmci_context.c:497 [inline] vmci_ctx_enqueue_datagram+0x4dc/0x620 drivers/misc/vmw_vmci/vmci_context.c:360 dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:275 [inline] vmci_datagram_dispatch+0x39b/0xb50 drivers/misc/vmw_vmci/vmci_datagram.c:339 qp_notify_peer+0x182/0x260 drivers/misc/vmw_vmci/vmci_queue_pair.c:1479 vmci_qp_broker_detach+0xa09/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2186 ctx_free_ctx+0x4cc/0xd30 drivers/misc/vmw_vmci/vmci_context.c:444 kref_put include/linux/kref.h:65 [inline] vmci_ctx_put drivers/misc/vmw_vmci/vmci_context.c:497 [inline] vmci_ctx_destroy+0x169/0x1d0 drivers/misc/vmw_vmci/vmci_context.c:195 vmci_host_close+0x116/0x1a0 drivers/misc/vmw_vmci/vmci_host.c:143 __fput+0x286/0x9f0 fs/file_table.c:317 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:190 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:222 __syscall_exit_to_user_mode_work kernel/entry/common.c:304 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:315 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc0f223bc8b Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffe26bd8ad0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007fc0f223bc8b RDX: 0000001b33a20000 RSI: 0000001b33a222a4 RDI: 0000000000000004 RBP: 00007fc0f239d960 R08: 0000000000000000 R09: 00000000ddbc5e63 R10: 00007ffe26be4090 R11: 0000000000000293 R12: 00000000000292bd R13: 00007ffe26bd8bd0 R14: 00007ffe26bd8bf0 R15: 0000000000000032