static int simulate_sync(struct pt_regs *regs, unsigned int opcode)
{
	if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC) {
		perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
				1, 0, regs, 0);
		return 0;
	}

	return -1;			/* Must be something else ... */
}
The software does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.