linux-kernel - Re: [PATCH Part1 RFC v2 11/20] x86/compressed: Add helper for validating pages in the decompression stage

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Message-ID: <YKzO2+Dwb5ABKFyF@zn.tnic>
Date:   Tue, 25 May 2021 12:18:03 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Brijesh Singh <brijesh.singh@....com>
Cc:     x86@...nel.org, linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        tglx@...utronix.de, jroedel@...e.de, thomas.lendacky@....com,
        pbonzini@...hat.com, mingo@...hat.com, dave.hansen@...el.com,
        rientjes@...gle.com, seanjc@...gle.com, peterz@...radead.org,
        hpa@...or.com, tony.luck@...el.com
Subject: Re: [PATCH Part1 RFC v2 11/20] x86/compressed: Add helper for
 validating pages in the decompression stage

On Thu, May 20, 2021 at 01:05:15PM -0500, Brijesh Singh wrote:
> Maybe I am missing something, the statement above was executed for
> either set or clr but the page shared need to happen only for clr. So,
> from code readability point I kept it outside of that if().
> 
> Otherwise we may have to do something like.
> 
> ...
> 
> if ((set | clr) & _PAGE_EN) {
> 
>    if (clr)
> 
>     snp_set_page_shared(pte_pfn(*ptep) << PAGE_SHIFT);
> 
>   }
> 
> I am okay with above is the preferred approach.

Yes pls, because it keeps the _PAGE_ENC handling together in one
statement.

Thx.

-- 
Regards/Gruss,
    Boris.

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