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Fri, 3 Apr 2026 22:05:12 +0000 Message-ID: Date: Fri, 3 Apr 2026 15:05:10 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/7] KVM: x86: APX reg prep work To: Paolo Bonzini , Sean Christopherson CC: Kiryl Shutsemau , , , , References: <20260311003346.2626238-1-seanjc@google.com> <7ec084f8-812e-42f2-8470-e416fa7ee848@redhat.com> <88e9d7f0-35b8-4559-9f4d-c7daf1af6012@redhat.com> Content-Language: en-US From: "Chang S. 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Right, I'd much prefer this. Then, it requires to audit whether any fast-path handler could access EGPRs. But there are cases with the new {RD|WR}MSR (MSR_IMM) instructions that appear to access GPRs. Because of this, the EGPR saving/restoring needs to happen earlier.