On Mon, Sep 21, 2020 at 12:17:00PM -0700, Sean Christopherson wrote: > That was effectively my original suggestion as well, check for a stale cache > and retry indefinitely. I capitulated because it did feel like I was being > overly paranoid. I'm obviously ok going the retry indefinitely route :-). > > https://lkml.kernel.org/r/20180904163546.GA5421@xxxxxxxxxxxxxxx Right, so if EINIT is so expensive, why does it matter how many cyccles WRMSR has? I.e., you don't really need to cache - you simply write the 4 MSRs and you're done. Simple. As to "indefinitely" - caller can increment a counter which counts how many times it returned SGX_INVALID_EINITTOKEN. I guess when it reaches some too high number which should not be reached during normal usage patterns, you can give up and issue a message to say that counter reached max retries or so but other than that, you should be ok. That thing is running interruptible in a loop anyway... Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette
