============================================ WARNING: possible recursive locking detected 6.6.0-syzkaller-10265-gbabe393974de #0 Not tainted -------------------------------------------- syz-executor.4/16405 is trying to acquire lock: ffffffff8ddc7dd8 (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: ffffffff8ddc7dd8 (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-executor.4/16405: #0: ffffffff8ddc7dd8 (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: 16405 Comm: syz-executor.4 Not tainted 6.6.0-syzkaller-10265-gbabe393974de #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 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:3062 [inline] validate_chain kernel/locking/lockdep.c:3855 [inline] __lock_acquire+0x2971/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __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+0x4f3/0xd90 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+0x4f3/0xd90 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+0x270/0xbb0 fs/file_table.c:394 __fput_sync+0x47/0x50 fs/file_table.c:475 __do_sys_close fs/open.c:1590 [inline] __se_sys_close fs/open.c:1575 [inline] __x64_sys_close+0x87/0xf0 fs/open.c:1575 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fb155e7b9da Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24 RSP: 002b:00007fb1560bfb10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fb155e7b9da RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000032 R08: 0000001b30f20000 R09: 0000000000000020 R10: 000000008173f3c3 R11: 0000000000000293 R12: 00007fb155a00620 R13: ffffffffffffffff R14: 00007fb155a00000 R15: 00000000000b86f9