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Date:   Tue, 26 Oct 2021 14:58:44 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Joerg Roedel <joro@8bytes.org>
Cc:     x86@kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, hpa@zytor.com,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Joerg Roedel <jroedel@suse.de>,
        Mike Rapoport <rppt@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Brijesh Singh <brijesh.singh@amd.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 2/4] x86/mm/64: Flush global TLB on boot and AP bringup
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References: <20211001154817.29225-1-joro@8bytes.org>
 <20211001154817.29225-3-joro@8bytes.org>
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On Tue, Oct 26, 2021 at 11:55:44AM +0200, Borislav Petkov wrote:
> > +	movq	%cr4, %rcx
> > +	movq	%rcx, %rax
> > +	xorq	$X86_CR4_PGE, %rcx
> > +	movq	%rcx, %cr4
> > +	movq	%rax, %cr4

Also, I'm wondering if you could compact this even more by defining a
function toggling the PGE bit and calling it from everywhere, even from
asm.

-- 
Regards/Gruss,
    Boris.

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