linux-kernel - Re: [RFC PATCH V2 01/18] x86/sev: Pvalidate memory gab for decompressing kernel

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Message-ID: <Y4Yjt0rOzsSoosEj@zn.tnic>
Date:   Tue, 29 Nov 2022 16:22:31 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Tianyu Lan <ltykernel@...il.com>
Cc:     luto@...nel.org, tglx@...utronix.de, mingo@...hat.com,
        dave.hansen@...ux.intel.com, x86@...nel.org, hpa@...or.com,
        seanjc@...gle.com, pbonzini@...hat.com, jgross@...e.com,
        tiala@...rosoft.com, kirill@...temov.name,
        jiangshan.ljs@...group.com, peterz@...radead.org,
        ashish.kalra@....com, srutherford@...gle.com,
        akpm@...ux-foundation.org, anshuman.khandual@....com,
        pawan.kumar.gupta@...ux.intel.com, adrian.hunter@...el.com,
        daniel.sneddon@...ux.intel.com, alexander.shishkin@...ux.intel.com,
        sandipan.das@....com, ray.huang@....com, brijesh.singh@....com,
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        linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        linux-hyperv@...r.kernel.org, linux-arch@...r.kernel.org
Subject: Re: [RFC PATCH V2 01/18] x86/sev: Pvalidate memory gab for
 decompressing kernel

On Tue, Nov 29, 2022 at 10:42:48PM +0800, Tianyu Lan wrote:
> Thanks for your review. sev_snp_enabled() is used after sev_status
> was initialized in sev_enable() while pvalidate_for_startup_ 64() is
> called before sev_enable().

Then you're going to have to change the code so that sev_status is
initialized before you need it. And not break others in the process.

And lemme save you some time - I won't accept sloppy code. You need to
integrate the functionality you need in the code paths properly - not
bolt it on in complete disregard of the flow just because it is easier.

> This is for Linux direct boot mode and so it needs to do such check
> here.

I don't know what "Linux direct boot mode" is so until you define it
properly and explain everything in detail, this is not going anywhere.

Thx.

-- 
Regards/Gruss,
    Boris.

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