When a line is cached, the type of transaction is stored in the cache. If the line has been updated upon a secure transaction, only secure transaction can hit, otherwise there is a cache miss and the transaction propagates to the NVMCTRL which enforces the security. If the line has been updated upon a non-secure transaction, it can be hit by both the secure or non-secure transactions. In case of a non-secure transaction cache miss, a line is replaced even if it contained a secure data.