megasas_fire_cmd_xscale(struct megasas_instance *instance,
		dma_addr_t frame_phys_addr,
		u32 frame_count,
		struct megasas_register_set __iomem *regs)
{
	unsigned long flags;

	spin_lock_irqsave(&instance->hba_lock, flags);
	writel((frame_phys_addr >> 3)|(frame_count),
	       &(regs)->inbound_queue_port);
	spin_unlock_irqrestore(&instance->hba_lock, flags);
}

The product dereferences a pointer that it expects to be valid but is NULL.