On 5/12/20 4:58 PM, Babu Moger wrote: > +config X86_MEMORY_PROTECTION_KEYS > + # Both Intel and AMD platforms support "Memory Protection Keys" > + # feature. So add a generic option X86_MEMORY_PROTECTION_KEYS > + # and set the option whenever X86_INTEL_MEMORY_PROTECTION_KEYS > + # is set. This is to avoid the confusion about the feature > + # availability on AMD platforms. Also renaming the old option > + # would cause the user an extra prompt during the kernel > + # configuration. So avoided changing the old config name. > + def_bool X86_INTEL_MEMORY_PROTECTION_KEYS Hi Babu, I made a request earlier for an end date (or version) to be included here. I believe that appeared in one of your earlier versions, but it was removed in later ones. Was there a reason for that? I'd really prefer to put some kind of expiration date on the config option. It will outlive us all otherwise. > Memory Protection Keys for Userspace (PKU aka PKEYs) is a feature > which is found on Intel's Skylake "Scalable Processor" Server CPUs. > -It will be avalable in future non-server parts. > +It will be available in future non-server parts. Also, AMD64 > +Architecture Programmer’s Manual defines PKU feature in AMD processors. I actually worked pretty hard to make that sentence useful to Linux users. Instead of forcing them to imply that it will be available on future AMD CPUs, can we just come out and say it? Can we give any more information to our users? Naming the AMD manual in which the feature is defined doesn't really help our users. Let's not waste the bytes on it. How about: Memory Protection Keys for Userspace (PKU aka PKEYs) is a feature which is found on Intel's Skylake (and later) "Scalable Processor" Server CPUs. It will be avalable in future non- server Intel parts and future AMD parts. Any clarity you can add, such as to say what AMD is doing for server vs. client would be nice. BTW, when I first submitted pkeys, I didn't have any statement like this in the changelog or documentation. Ingo, I think, asked for it and I worked with folks inside Intel to figure out how much we could say publicly about our plans. A similar effort from AMD would be much appreciated here.
