============================================ WARNING: possible recursive locking detected 6.15.0-syzkaller-12426-ge271ed52b344 #0 Not tainted -------------------------------------------- syz-executor.3/31934 is trying to acquire lock: ffffffff8f54dfb8 (qp_broker_list.mutex){+.+.}-{4:4}, at: vmci_qp_broker_detach+0x14c/0x1380 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 but task is already holding lock: ffffffff8f54dfb8 (qp_broker_list.mutex){+.+.}-{4:4}, at: vmci_qp_broker_detach+0x14c/0x1380 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.3/31934: #0: ffffffff8f54dfb8 (qp_broker_list.mutex){+.+.}-{4:4}, at: vmci_qp_broker_detach+0x14c/0x1380 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 stack backtrace: CPU: 1 UID: 0 PID: 31934 Comm: syz-executor.3 Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_deadlock_bug+0x1e9/0x240 kernel/locking/lockdep.c:3044 check_deadlock kernel/locking/lockdep.c:3096 [inline] validate_chain kernel/locking/lockdep.c:3898 [inline] __lock_acquire+0x1106/0x1c90 kernel/locking/lockdep.c:5240 lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828 __mutex_lock_common kernel/locking/mutex.c:602 [inline] __mutex_lock+0x199/0xb90 kernel/locking/mutex.c:747 vmci_qp_broker_detach+0x14c/0x1380 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 ctx_free_ctx+0x4f5/0xd70 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_context_get_priv_flags drivers/misc/vmw_vmci/vmci_context.c:1185 [inline] vmci_context_get_priv_flags+0xd4/0x100 drivers/misc/vmw_vmci/vmci_context.c:1174 dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:255 [inline] vmci_datagram_dispatch+0x30f/0xd30 drivers/misc/vmw_vmci/vmci_datagram.c:340 qp_notify_peer+0x19d/0x260 drivers/misc/vmw_vmci/vmci_queue_pair.c:1481 vmci_qp_broker_detach+0x604/0x1380 drivers/misc/vmw_vmci/vmci_queue_pair.c:2188 ctx_free_ctx+0x4f5/0xd70 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+0x15b/0x1d0 drivers/misc/vmw_vmci/vmci_context.c:195 vmci_host_close+0x115/0x1a0 drivers/misc/vmw_vmci/vmci_host.c:143 __fput+0x402/0xb70 fs/file_table.c:465 fput_close_sync+0x118/0x260 fs/file_table.c:570 __do_sys_close fs/open.c:1589 [inline] __se_sys_close fs/open.c:1574 [inline] __x64_sys_close+0x8b/0x120 fs/open.c:1574 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb47f67b9da 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:00007fff9280f950 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fb47f67b9da RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000032 R08: 0000001b30560000 R09: 00007fb47f79bf8c R10: 00007fff9280faa0 R11: 0000000000000293 R12: 00007fb47f200478 R13: ffffffffffffffff R14: 00007fb47f200000 R15: 000000000003b4e1