From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030597Ab2HWP55 (ORCPT ); Thu, 23 Aug 2012 11:57:57 -0400 Received: from smtp.ctxuk.citrix.com ([62.200.22.115]:56508 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934087Ab2HWP5x (ORCPT ); Thu, 23 Aug 2012 11:57:53 -0400 X-IronPort-AV: E=Sophos;i="4.80,300,1344211200"; d="scan'208";a="14151314" Date: Thu, 23 Aug 2012 16:57:29 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Konrad Rzeszutek Wilk CC: Stefano Stabellini , Ian Campbell , "linux-kernel@vger.kernel.org" , "xen-devel@lists.xensource.com" Subject: Re: [Xen-devel] [PATCH 06/11] xen/mmu: For 64-bit do not call xen_map_identity_early In-Reply-To: <20120823154012.GA18845@phenom.dumpdata.com> Message-ID: References: <1345133009-21941-1-git-send-email-konrad.wilk@oracle.com> <1345133009-21941-7-git-send-email-konrad.wilk@oracle.com> <20120817174549.GA14257@phenom.dumpdata.com> <1345463624.28762.67.camel@zakaz.uk.xensource.com> <20120823154012.GA18845@phenom.dumpdata.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 23 Aug 2012, Konrad Rzeszutek Wilk wrote: > >From 43fd7a5d9ecd31c2fc26851523cd4b5f7650fb39 Mon Sep 17 00:00:00 2001 > From: Konrad Rzeszutek Wilk > Date: Thu, 12 Jul 2012 13:59:36 -0400 > Subject: [PATCH] xen/mmu: For 64-bit do not call xen_map_identity_early > > B/c we do not need it. During the startup the Xen provides ^ remove the > us with all the initial memory mapped that we need to function. > > The initial memory mapped is up to the bootstack, which means > we can reference using __ka up to 4.f): Thanks, that is what I was looking for. > (from xen/interface/xen.h): > > 4. This the order of bootstrap elements in the initial virtual region: > a. relocated kernel image > b. initial ram disk [mod_start, mod_len] > c. list of allocated page frames [mfn_list, nr_pages] > d. start_info_t structure [register ESI (x86)] > e. bootstrap page tables [pt_base, CR3 (x86)] > f. bootstrap stack [register ESP (x86)] > > (initial ram disk may be ommitted). > > [v1: More comments in git commit] > Signed-off-by: Konrad Rzeszutek Wilk Acked-by: Stefano Stabellini > --- > arch/x86/xen/mmu.c | 11 +++++------ > 1 files changed, 5 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c > index 7247e5a..a59070b 100644 > --- a/arch/x86/xen/mmu.c > +++ b/arch/x86/xen/mmu.c > @@ -84,6 +84,7 @@ > */ > DEFINE_SPINLOCK(xen_reservation_lock); > > +#ifdef CONFIG_X86_32 > /* > * Identity map, in addition to plain kernel map. This needs to be > * large enough to allocate page table pages to allocate the rest. > @@ -91,7 +92,7 @@ DEFINE_SPINLOCK(xen_reservation_lock); > */ > #define LEVEL1_IDENT_ENTRIES (PTRS_PER_PTE * 4) > static RESERVE_BRK_ARRAY(pte_t, level1_ident_pgt, LEVEL1_IDENT_ENTRIES); > - > +#endif > #ifdef CONFIG_X86_64 > /* l3 pud for userspace vsyscall mapping */ > static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss; > @@ -1628,7 +1629,7 @@ static void set_page_prot(void *addr, pgprot_t prot) > if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0)) > BUG(); > } > - > +#ifdef CONFIG_X86_32 > static void __init xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) > { > unsigned pmdidx, pteidx; > @@ -1679,7 +1680,7 @@ static void __init xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn) > > set_page_prot(pmd, PAGE_KERNEL_RO); > } > - > +#endif > void __init xen_setup_machphys_mapping(void) > { > struct xen_machphys_mapping mapping; > @@ -1765,14 +1766,12 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) > /* Note that we don't do anything with level1_fixmap_pgt which > * we don't need. */ > > - /* Set up identity map */ > - xen_map_identity_early(level2_ident_pgt, max_pfn); > - > /* Make pagetable pieces RO */ > set_page_prot(init_level4_pgt, PAGE_KERNEL_RO); > set_page_prot(level3_ident_pgt, PAGE_KERNEL_RO); > set_page_prot(level3_kernel_pgt, PAGE_KERNEL_RO); > set_page_prot(level3_user_vsyscall, PAGE_KERNEL_RO); > + set_page_prot(level2_ident_pgt, PAGE_KERNEL_RO); > set_page_prot(level2_kernel_pgt, PAGE_KERNEL_RO); > set_page_prot(level2_fixmap_pgt, PAGE_KERNEL_RO); > > -- > 1.7.7.6 >