On 1/15/21 6:04 PM, Eric Biggers wrote: > On Fri, Jan 15, 2021 at 04:20:44PM -0800, Dave Hansen wrote: >> On 1/15/21 4:14 PM, Dey, Megha wrote: >>> Also, I do not know of any cores that implement PCLMULQDQ and not AES-NI. >> That's true, bit it's also possible that a hypervisor could enumerate >> support for PCLMULQDQ and not AES-NI. In general, we've tried to >> implement x86 CPU features independently, even if they never show up in >> a real CPU independently. > We only add optimized implementations of crypto algorithms if they are > actually > useful, though. If they would never be used in practice, that's not useful.
Yes, totally agree. If it's not of practical use, it doesn't get merged. I just wanted to share what we do for other related but independent CPU features.
