linux-kernel - Re: [PATCH] x86/paravirt: Fix build PARAVIRT_XXL=y without XEN

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YZYZQap45Jg+SPqp@zn.tnic>
Date:   Thu, 18 Nov 2021 10:13:37 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@...ux.intel.com>
Cc:     Dave Hansen <dave.hansen@...el.com>,
        "Kirill A. Shutemov" <kirill@...temov.name>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        Andi Kleen <ak@...ux.intel.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Juergen Gross <jgross@...e.com>, Deep Shah <sdeep@...are.com>,
        "VMware, Inc." <pv-drivers@...are.com>
Subject: Re: [PATCH] x86/paravirt: Fix build PARAVIRT_XXL=y without XEN_PV

On Wed, Nov 17, 2021 at 05:26:15PM -0800, Sathyanarayanan Kuppuswamy wrote:
> I meant it not scalable because, for any new use case of HLT
> instruction, it would need substitution again. We cannot always keep
> tracking its uses in the future, right?

I don't understand what the whole hoopla is about:

	alternative_call(halt, tdx_halt, X86_FEATURE_TDX_GUEST, ...)

No PV needed.

> Also, If we make any changes to the core emulation code (like arguments
> change), we will have to re-touch these use cases to handle it.

We do change the core code all the time to accomodate new stuff. You
should be seeing that constantly with the rate of change happening...

-- 
Regards/Gruss,
    Boris.

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