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Peter Anvin" Content-Type: text/plain; charset="us-ascii" On Mon, May 12, 2025, mlevitsk@redhat.com wrote: > On Wed, 2025-05-07 at 10:18 -0700, Sean Christopherson wrote: > AFAIK the KVM convention for msr writes is that 1 is GP, 0 success, and > negative value exits as a KVM internal error to userspace. Not very developer > friendly IMHO, there is a room for improvement here. Yeah, it's ugly. You're definitely not the first person to complain about KVM's error code shenanigans. Unfortunately, disentangling everything and doing so in a way that is maintainable in the long term would be quite tricky, and absurdly invasive. :-/