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Date: Thu, 25 Feb 2016 09:10:44 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andrew Cooper <andrew.cooper3@citrix.com>,
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        David Vrabel <david.vrabel@citrix.com>, Borislav Petkov <bp@alien8.de>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        X86 ML <x86@kernel.org>, Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH v3 01/11] x86/boot: enumerate documentation for the x86
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* Andy Lutomirski <luto@amacapital.net> wrote:

> On Feb 24, 2016 12:33 AM, "Ingo Molnar" <mingo@kernel.org> wrote:
> >
> > For hard coded platform quirks I'd suggest we add x86_platform.quirks flags. For
> > example the F00F hack for Xen could be done via:
> >
> >         x86_platform.quirks.idt_remap = 0;
> >
> 
> Don't we unconditionally remap the IDT?  I think Kees did it for
> general purpose hardening due to our complete inability to hide the
> IDT address. I.e. I think we can remove the f00f condition entirely.

Yeah, indeed - I only judged by the (limited) patch context and assumed the Xen 
problem was with IDT remapping.

But what the quirk really does is only to avoid printing the f00f workaround - 
i.e. a cosmetic change. I think we should just drop the paravirt_enabled() check.

Thanks,

	Ingo