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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Fri, 15 Sep 2023 13:59:28 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Steve Rutherford <srutherford@google.com>
Cc:     Borislav Petkov <bp@alien8.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H . Peter Anvin" <hpa@zytor.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, David.Kaplan@amd.com,
        jacobhxu@google.com, patelsvishal@google.com, bhillier@google.com
Subject: Re: [PATCH] x86/sev: Make early_set_memory_decrypted() calls page
 aligned
Message-ID: <ZQRHIN7as8f+PFeh@gmail.com>
References: <20230818233451.3615464-1-srutherford@google.com>
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* Steve Rutherford <srutherford@google.com> wrote:

> early_set_memory_decrypted() assumes its parameters are page aligned.
> Non-page aligned calls result in additional pages being marked as
> decrypted via the encryption status hypercall, which results in
> consistent corruption of pages during live migration. Live
> migration requires accurate encryption status information to avoid
> migrating pages from the wrong perspective.
> 
> Fixes: 4716276184ec ("X86/KVM: Decrypt shared per-cpu variables when SEV is active")
> Signed-off-by: Steve Rutherford <srutherford@google.com>
> ---
>  arch/x86/kernel/kvm.c | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)

I suppose this fix is going through the KVM tree, or should we pick it up
in the x86 tree?

Thanks,

	Ingo