ci starts bisection 2023-03-18 02:36:57.213877281 +0000 UTC m=+22900.493254365 bisecting fixing commit since e7c124bd04631973a3cc0df19ab881b56d8a2d50 building syzkaller on 6cc879d4712dbaf6e97f01250e2f4906c07b24b8 ensuring issue is reproducible on original commit e7c124bd04631973a3cc0df19ab881b56d8a2d50 testing commit e7c124bd04631973a3cc0df19ab881b56d8a2d50 gcc compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: c9e334d3478168c8318e498c085671f87cc64f96cb8130ff52123ad816c04437 run #0: crashed: possible deadlock in vmci_qp_broker_detach run #1: crashed: possible deadlock in vmci_qp_broker_detach run #2: crashed: possible deadlock in vmci_qp_broker_detach run #3: crashed: possible deadlock in vmci_qp_broker_detach run #4: crashed: possible deadlock in vmci_qp_broker_detach run #5: crashed: possible deadlock in vmci_qp_broker_detach run #6: crashed: possible deadlock in vmci_qp_broker_detach run #7: crashed: possible deadlock in vmci_qp_broker_detach run #8: crashed: possible deadlock in vmci_qp_broker_detach run #9: crashed: possible deadlock in vmci_qp_broker_detach run #10: crashed: possible deadlock in vmci_qp_broker_detach run #11: crashed: possible deadlock in vmci_qp_broker_detach run #12: crashed: possible deadlock in vmci_qp_broker_detach run #13: crashed: possible deadlock in vmci_qp_broker_detach run #14: crashed: possible deadlock in vmci_qp_broker_detach run #15: crashed: possible deadlock in vmci_qp_broker_detach run #16: crashed: possible deadlock in vmci_qp_broker_detach run #17: crashed: possible deadlock in vmci_qp_broker_detach run #18: crashed: possible deadlock in vmci_qp_broker_detach run #19: OK testing current HEAD 478a351ce0d69cef2d2bf2a686a09b356b63a66c testing commit 478a351ce0d69cef2d2bf2a686a09b356b63a66c gcc compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: ba057b988ba2ae8c0e484cc80d324c56ca7704566f2f483d8621fcbc446de746 all runs: crashed: possible deadlock in vmci_qp_broker_detach revisions tested: 2, total time: 37m48.349465684s (build: 14m21.555975859s, test: 22m15.459225338s) the crash still happens on HEAD commit msg: Merge tag 'net-6.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net crash: possible deadlock in vmci_qp_broker_detach ============================================ WARNING: possible recursive locking detected 6.3.0-rc2-syzkaller #0 Not tainted -------------------------------------------- syz-executor157/24849 is trying to acquire lock: ffffffff8bcf6c58 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x11e/0x13a0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 but task is already holding lock: ffffffff8bcf6c58 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x11e/0x13a0 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-executor157/24849: #0: ffffffff8bcf6c58 (qp_broker_list.mutex){+.+.}-{3:3}, at: vmci_qp_broker_detach+0x11e/0x13a0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 stack backtrace: CPU: 1 PID: 24849 Comm: syz-executor157 Not tainted 6.3.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x64/0xb0 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+0x11e/0x13a0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2095 ctx_free_ctx+0x410/0xc30 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+0x3e2/0x590 drivers/misc/vmw_vmci/vmci_context.c:360 dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:275 [inline] vmci_datagram_dispatch+0x2cb/0x960 drivers/misc/vmw_vmci/vmci_datagram.c:339 qp_notify_peer+0x147/0x210 drivers/misc/vmw_vmci/vmci_queue_pair.c:1481 vmci_qp_broker_detach+0x863/0x13a0 drivers/misc/vmw_vmci/vmci_queue_pair.c:2188 ctx_free_ctx+0x410/0xc30 drivers/misc/vmw_vmci/vmci_context.c:444 vmci_host_close+0xf6/0x180 drivers/misc/vmw_vmci/vmci_host.c:143 __fput+0x1fa/0x9a0 fs/file_table.c:321 task_work_run+0x12f/0x220 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x92c/0x2480 kernel/exit.c:869 do_group_exit+0xb4/0x250 kernel/exit.c:1019 get_signal+0x1d36/0x1fa0 kernel/signal.c:2859 arch_do_signal_or_restart+0x79/0x5a0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0x80 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f7cad838a19 Code: Unable to access opcode bytes at 0x7f7cad8389ef. RSP: 002b:00007f7cad7ea308 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f7cad8c03e8 RCX: 00007f7cad838a19 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f7cad8c03ec RBP: 00007f7cad8c03e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7cad8c03ec R13: 00007f7cad88e064 R14: 636d762f7665642f R15: 0000000000022000