linux-kernel - Re: [PATCH v5 5/5] x86/kvm: Avoid dynamic allocation of pvclock data when SEV is active

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Message-ID: <20180906144444.GC11144@zn.tnic>
Date:   Thu, 6 Sep 2018 16:44:44 +0200
From:   Borislav Petkov <bp@...e.de>
To:     Sean Christopherson <sean.j.christopherson@...el.com>
Cc:     Brijesh Singh <brijesh.singh@....com>, x86@...nel.org,
        linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        Tom Lendacky <thomas.lendacky@....com>,
        Thomas Gleixner <tglx@...utronix.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>
Subject: Re: [PATCH v5 5/5] x86/kvm: Avoid dynamic allocation of pvclock data
 when SEV is active

On Thu, Sep 06, 2018 at 07:18:25AM -0700, Sean Christopherson wrote:
> Oh, and we'd need to make sure __decrypted_exclusive is freed when
> !CONFIG_AMD_MEM_ENCRYPT, and preferably !sev_active() since the big
> array is used only if SEV is active.  This patch unconditionally
> defines hv_clock_dec but only frees it if CONFIG_AMD_MEM_ENCRYPT=y &&
> !mem_encrypt_active().

We should not go nuts and complicate the code only to save us a couple
of KBs.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--