============================================ WARNING: possible recursive locking detected 6.5.0-rc6-syzkaller-00027-g91aa6c412d7f #0 Not tainted -------------------------------------------- syz-executor229/2777 is trying to acquire lock: ffffffff8d70c498 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x14d/0x1370 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 but task is already holding lock: ffffffff8d70c498 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x14d/0x1370 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 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-executor229/2777: #0: ffffffff8d70c498 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x14d/0x1370 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 stack backtrace: CPU: 0 PID: 2777 Comm: syz-executor229 Not tainted 6.5.0-rc6-syzkaller-00027-g91aa6c412d7f #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_deadlock kernel/locking/lockdep.c:3070 [inline] validate_chain kernel/locking/lockdep.c:3863 [inline] __lock_acquire+0x2971/0x5de0 kernel/locking/lockdep.c:5144 lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 vmci_qp_broker_detach+0x14d/0x1370 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 ctx_free_ctx+0x4fa/0xda0 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/0x690 drivers/misc/vmw_vmci/vmci_context.c:360 dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:275 [inline] vmci_datagram_dispatch+0x42c/0xcd0 drivers/misc/vmw_vmci/vmci_datagram.c:339 qp_notify_peer+0x19e/0x260 drivers/misc/vmw_vmci/vmci_queue_pair.c:1481 vmci_qp_broker_detach+0x5f7/0x1370 drivers/misc/vmw_vmci/vmci_queue_pair.c:2188 ctx_free_ctx+0x4fa/0xda0 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+0x16d/0x1e0 drivers/misc/vmw_vmci/vmci_context.c:195 vmci_host_close+0x11a/0x1b0 drivers/misc/vmw_vmci/vmci_host.c:143 __fput+0x3f7/0xac0 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa99/0x2a20 kernel/exit.c:874 do_group_exit+0xd4/0x2a0 kernel/exit.c:1024 get_signal+0x23ea/0x2770 kernel/signal.c:2881 arch_do_signal_or_restart+0x89/0x5f0 arch/x86/kernel/signal.c:308 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f0a302af499 Code: Unable to access opcode bytes at 0x7f0a302af46f. RSP: 002b:00007f0a30270228 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f0a30339308 RCX: 00007f0a302af499 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0a30339308 RBP: 00007f0a30339300 R08: 00007f0a302706c0 R09: 00007f0a302706c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0a3033930c R13: 00007f0a30306074 R14: 636d762f7665642f R15: 00007ffc6bbd99c8