============================================ WARNING: possible recursive locking detected 6.3.0-rc5-syzkaller-00137-gf2afccfefe7b #0 Not tainted -------------------------------------------- syz-executor.1/9417 is trying to acquire lock: ffffffff8d483538 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x14b/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 but task is already holding lock: ffffffff8d483538 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x14b/0x11b0 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.1/9417: #0: ffffffff8d483538 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x14b/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 stack backtrace: CPU: 0 PID: 9417 Comm: syz-executor.1 Not tainted 6.3.0-rc5-syzkaller-00137-gf2afccfefe7b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2991 [inline] check_deadlock kernel/locking/lockdep.c:3034 [inline] validate_chain kernel/locking/lockdep.c:3819 [inline] __lock_acquire+0x1362/0x5d40 kernel/locking/lockdep.c:5056 lock_acquire kernel/locking/lockdep.c:5669 [inline] lock_acquire+0x1af/0x520 kernel/locking/lockdep.c:5634 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x12f/0x1350 kernel/locking/mutex.c:747 vmci_qp_broker_detach+0x14b/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 ctx_free_ctx+0x4cc/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_enqueue_datagram+0x4e0/0x6c0 drivers/misc/vmw_vmci/vmci_context.c:360 dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:275 [inline] vmci_datagram_dispatch+0x430/0xc60 drivers/misc/vmw_vmci/vmci_datagram.c:339 qp_notify_peer+0x194/0x290 drivers/misc/vmw_vmci/vmci_queue_pair.c:1481 vmci_qp_broker_detach+0xa0d/0x11b0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2188 ctx_free_ctx+0x4cc/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+0x16d/0x1e0 drivers/misc/vmw_vmci/vmci_context.c:195 vmci_host_close+0x11a/0x1b0 drivers/misc/vmw_vmci/vmci_host.c:143 __fput+0x27c/0xa90 fs/file_table.c:321 task_work_run+0x16f/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x210/0x240 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_fast_syscall_32+0x72/0xf0 arch/x86/entry/common.c:181 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f4e579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f749fb10 EFLAGS: 00000286 ORIG_RAX: 0000000000000006 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 00000000f734e000 RDI: 0000000000000000 RBP: 00000000f6e00968 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 retq 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi