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I >>>> think you're aware of this but wanted to point that out just in case. >>> >>> I view it as a performance problem because nothing stops KVM from copying from >>> userspace into the private fd during the SEV ioctl(). What's missing is the >>> ability for userspace to directly initialze the private fd, which may or may not >>> avoid an extra memcpy() depending on how clever userspace is. >> Can you please elaborate more what you see as a performance problem? And >> possible ways to solve it? > > Oh, I'm not saying there actually _is_ a performance problem. What I'm saying is > that in-place encryption is not a functional requirement, which means it's purely > an optimization, and thus we should other bother supporting in-place encryption > _if_ it would solve a performane bottleneck. Understood. Thank you! Best regards, Pankaj