Re: [PATCHv2 08/10] x86/mm: Replace compile-time checks for 5-level with runtime-time

From: Kirill A. Shutemov
Date: Tue Jul 18 2017 - 11:16:24 EST


On Tue, Jul 18, 2017 at 04:24:06PM +0200, Juergen Gross wrote:
> On 18/07/17 16:15, Kirill A. Shutemov wrote:
> > diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
> > index cab28cf2cffb..b0530184c637 100644
> > --- a/arch/x86/xen/mmu_pv.c
> > +++ b/arch/x86/xen/mmu_pv.c
> > @@ -1209,7 +1209,7 @@ static void __init xen_cleanmfnmap(unsigned long vaddr)
> > continue;
> > xen_cleanmfnmap_p4d(p4d + i, unpin);
> > }
> > - if (IS_ENABLED(CONFIG_X86_5LEVEL)) {
> > + if (!p4d_folded) {
> > set_pgd(pgd, __pgd(0));
> > xen_cleanmfnmap_free_pgtbl(p4d, unpin);
> > }
>
> Xen PV guests will never run with 5-level-paging enabled. So I guess you
> can drop the complete if (IS_ENABLED(CONFIG_X86_5LEVEL)) {} block.

Thanks.

I'll do a sparate cleanup patch for this.

--
Kirill A. Shutemov