On 03/09/2018 12:12 AM, Ram Pai wrote: > Once an address range is associated with an allocated pkey, it cannot be > reverted back to key-0. There is no valid reason for the above behavior. On > the contrary applications need the ability to do so. Why don't we just set pkey 0 to be allocated in the allocation bitmap by default? We *could* also just not let it be special and let it be freed. An app could theoretically be careful and make sure nothing is using it.