Sender: Paolo Bonzini <paolo.bonzini@gmail.com>
Message-ID: <b9d59fee-e1d8-5f96-0b1d-f11c10d8b0f1@redhat.com>
Date:   Thu, 9 Dec 2021 19:55:25 +0100
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Subject: Re: [PATCH v2] KVM: x86: Always set kvm_run->if_flag
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To:     Marc Orr <marcorr@google.com>,
        Sean Christopherson <seanjc@google.com>
Cc:     Jim Mattson <jmattson@google.com>, vkuznets@redhat.com,
        wanpengli@tencent.com, joro@8bytes.org, tglx@linutronix.de,
        mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
        x86@kernel.org, hpa@zytor.com, Thomas.Lendacky@amd.com,
        mlevitsk@redhat.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
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From:   Paolo Bonzini <pbonzini@redhat.com>
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On 12/9/21 19:29, Marc Orr wrote:
> All that being said, after Jim added his Ack to this patch (which I
> forgot to attach to the v2), we realized that technically the ES
> patches were within their right to redefine if_flag since it's
> previous semantics are maintained for non-ES VMs and ES requires
> userspace changes anyway (PSP commands, guest memory pinning, etc.).

Correct, but it's a bit ugly to redefine the semantics and that is why I 
am going to apply the patch anyway.

Paolo

> I'm OK either way here. But I assume that if this flag is giving us
> pains it will give others pains. And this patch seems reasonable to
> me. So all things being equal, I'd prefer to proceed with it.
>