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Date: Fri, 27 Jul 2012 13:35:18 -0400 From: Konrad Rzeszutek Wilk <konrad@...nok.org> To: Stefano Stabellini <stefano.stabellini@...citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>, "xen-devel@...ts.xensource.com" <xen-devel@...ts.xensource.com>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org> Subject: Re: [Xen-devel] [PATCH 3/7] xen/mmu: Release the Xen provided L4 (PGD) back. On Fri, Jul 27, 2012 at 12:37:24PM +0100, Stefano Stabellini wrote: > On Thu, 26 Jul 2012, Konrad Rzeszutek Wilk wrote: > > Since we are not using it and somebody else could use it. > > make sense except it is almost entirely rewritten by the following > patch... Yeah, I should squash them. > > > Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com> > > --- > > arch/x86/xen/mmu.c | 13 +++++++------ > > 1 files changed, 7 insertions(+), 6 deletions(-) > > > > diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c > > index a59070b..48bdc9f 100644 > > --- a/arch/x86/xen/mmu.c > > +++ b/arch/x86/xen/mmu.c > > @@ -1782,20 +1782,21 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) > > /* Unpin Xen-provided one */ > > pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, PFN_DOWN(__pa(pgd))); > > > > - /* Switch over */ > > - pgd = init_level4_pgt; > > - > > /* > > * At this stage there can be no user pgd, and no page > > * structure to attach it to, so make sure we just set kernel > > * pgd. > > */ > > xen_mc_batch(); > > - __xen_write_cr3(true, __pa(pgd)); > > + __xen_write_cr3(true, __pa(init_level4_pgt)); > > xen_mc_issue(PARAVIRT_LAZY_CPU); > > > > - memblock_reserve(__pa(xen_start_info->pt_base), > > - xen_start_info->nr_pt_frames * PAGE_SIZE); > > + /* Offset by one page since the original pgd is going bye bye */ > > + memblock_reserve(__pa(xen_start_info->pt_base + PAGE_SIZE), > > + (xen_start_info->nr_pt_frames * PAGE_SIZE) - PAGE_SIZE); > > + /* and also RW it so it can actually be used. */ > > + set_page_prot(pgd, PAGE_KERNEL); > > + clear_page(pgd); > > } > > #else /* !CONFIG_X86_64 */ > > static RESERVE_BRK_ARRAY(pmd_t, initial_kernel_pmd, PTRS_PER_PMD); > > -- > > 1.7.7.6 > > > > > > _______________________________________________ > > Xen-devel mailing list > > Xen-devel@...ts.xen.org > > http://lists.xen.org/xen-devel > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@...ts.xen.org > http://lists.xen.org/xen-devel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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