===================================== WARNING: bad unlock balance detected! 4.14.292-syzkaller #0 Not tainted ------------------------------------- syz-executor956/8126 is trying to release lock (&file->mut) at: [] ucma_destroy_id+0x1eb/0x420 drivers/infiniband/core/ucma.c:606 but there are no more locks to release! other info that might help us debug this: 1 lock held by syz-executor956/8126: #0: (&file->mut){+.+.}, at: [] ucma_destroy_id+0x18c/0x420 drivers/infiniband/core/ucma.c:604 stack backtrace: CPU: 1 PID: 8126 Comm: syz-executor956 Not tainted 4.14.292-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_unlock_imbalance_bug include/trace/events/lock.h:58 [inline] __lock_release kernel/locking/lockdep.c:3769 [inline] lock_release.cold+0x70/0xbf kernel/locking/lockdep.c:4017 __mutex_unlock_slowpath+0x75/0x770 kernel/locking/mutex.c:1018 ucma_destroy_id+0x1eb/0x420 drivers/infiniband/core/ucma.c:606 ucma_write+0x206/0x2c0 drivers/infiniband/core/ucma.c:1672 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f45d87c9a69 RSP: 002b:00007f45d875a308 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f45d8851418 RCX: 00007f45d87c9a69 RDX: 0000000000000018 RSI: 0000000020000180 RDI: 0000000000000003 RBP: 00007f45d8851410 R08: 00007f45d875a700 R09: 0000000000000000 R10: 00007f45d875a700 R11: 0000000000000246 R12: 00007f45d885141c R13: 00007f45d881f074 R14: 006d635f616d6472 R15: 0000000000022000