Re: [PATCH v3 2/4] x86/mm/64: Flush global TLB on boot and AP bringup

From: Joerg Roedel
Date: Thu Dec 02 2021 - 07:50:19 EST


On Tue, Oct 26, 2021 at 02:58:44PM +0200, Borislav Petkov wrote:
> 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.

Yeah, that would make sense, but is probably worth its own patch-set.
Unifying this across arch/x86/ needs to touch a couple more places and
needs special care so that the function is safe to call from early asm.

Regards,

--
Jörg Rödel
jroedel@xxxxxxx

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