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Date:   Tue, 21 Sep 2021 16:51:23 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Sean Christopherson <seanjc@google.com>
Cc:     Ashish Kalra <ashish.kalra@amd.com>,
        Steve Rutherford <srutherford@google.com>, pbonzini@redhat.com,
        tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com,
        joro@8bytes.org, thomas.lendacky@amd.com, x86@kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        brijesh.singh@amd.com, dovmurik@linux.ibm.com, tobin@linux.ibm.com,
        jejb@linux.ibm.com, dgilbert@redhat.com
Subject: Re: [PATCH v6 1/5] x86/kvm: Add AMD SEV specific Hypercall3
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On Tue, Sep 21, 2021 at 01:50:09PM +0000, Sean Christopherson wrote:
> apply_alternatives() is a generic helper that can work on any struct alt_instr
> array, e.g. KVM_HYPERCALL can put its alternative into a different section that's
> patched as soon as the VMM is identified.

Where exactly in the boot process you wanna move it?

As Ashish says, you need the boot_cpu_data bits properly set before it
runs.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette