From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 419FEECE560 for ; Sun, 16 Sep 2018 14:31:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE41E20883 for ; Sun, 16 Sep 2018 14:31:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE41E20883 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728226AbeIPTyD (ORCPT ); Sun, 16 Sep 2018 15:54:03 -0400 Received: from mga11.intel.com ([192.55.52.93]:38763 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726852AbeIPTyC (ORCPT ); Sun, 16 Sep 2018 15:54:02 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Sep 2018 07:30:53 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,381,1531810800"; d="scan'208";a="83971591" Received: from shbuild888.sh.intel.com (HELO localhost) ([10.239.146.239]) by orsmga003.jf.intel.com with ESMTP; 16 Sep 2018 07:30:51 -0700 Date: Sun, 16 Sep 2018 22:35:49 +0800 From: Feng Tang To: Thomas Gleixner Cc: Michal Hocko , Peter Zijlstra , linux-kernel@vger.kernel.org, x86@kernel.org, Ingo Molnar , "H . Peter Anvin" , Yinghai Lu , Dave Hansen , Andi Kleen Subject: Re: [PATCH] x86, mm: Reserver some memory for bootmem allocator for NO_BOOTMEM Message-ID: <20180916143549.zmnlcviyn67fbxwh@shbuild888> References: <20180831133659.pkmscqpudjnkujbg@shbuild888> <20180907081716.bxw3hmcl6w7gqvax@shbuild888> <20180910093938.ka732apzy3d3a5ip@shbuild888> <20180911061413.redy4oxia3hqifkh@shbuild888> <20180915164731.3zrdxijuwkgdi25p@shbuild888> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 15, 2018 at 07:28:03PM +0200, Thomas Gleixner wrote: > On Sun, 16 Sep 2018, Feng Tang wrote: > > I have tried to change some header files incluing fixmap.h/apicdef.h/ > > vsyscall.h, and most of the .c files compile fine now, but I can not > > use the "__end_of_permanent_fixed_addresses" in head_64.S as it is a > > enum type, and could not be recognized by assembly code. > > Hrmm. I did not think about the enum. So we have two possibilities: > > 1) Have some preprocessing which provides the info for the assembler > > 2) Use a constant for the number of PMDs which is defined in a header and > then compile time checked against the size of the fixmap in a C-file. As there is no fixmap.c, I put the chck into __native_set_fixmap temply, please review, thanks - Feng diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h index e203169931c7..ffaa0fa31044 100644 --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -14,6 +14,9 @@ #ifndef _ASM_X86_FIXMAP_H #define _ASM_X86_FIXMAP_H +/* Put here to be accessble for assembly code like head_64.S */ +#define FIXMAP_PMD_NUM 2 + #ifndef __ASSEMBLY__ #include #include diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index f773d5e6c8cc..d6820d4c6e47 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -14,6 +14,7 @@ #include #include #include +#include extern p4d_t level4_kernel_pgt[512]; extern p4d_t level4_ident_pgt[512]; @@ -22,7 +23,7 @@ extern pud_t level3_ident_pgt[512]; extern pmd_t level2_kernel_pgt[512]; extern pmd_t level2_fixmap_pgt[512]; extern pmd_t level2_ident_pgt[512]; -extern pte_t level1_fixmap_pgt[512]; +extern pte_t level1_fixmap_pgt[512 * FIXMAP_PMD_NUM]; extern pgd_t init_top_pgt[]; #define swapper_pg_dir init_top_pgt diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index 15ebc2fc166e..985eaff70792 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -24,6 +24,7 @@ #include "../entry/calling.h" #include #include +#include #ifdef CONFIG_PARAVIRT #include @@ -445,13 +446,19 @@ NEXT_PAGE(level2_kernel_pgt) KERNEL_IMAGE_SIZE/PMD_SIZE) NEXT_PAGE(level2_fixmap_pgt) - .fill 506,8,0 - .quad level1_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC - /* 8MB reserved for vsyscalls + a 2MB hole = 4 + 1 entries */ - .fill 5,8,0 + .fill (512 - 4 - FIXMAP_PMD_NUM),8,0 + pgtno = 0 + .rept (FIXMAP_PMD_NUM) + .quad level1_fixmap_pgt + (pgtno << PAGE_SHIFT) - __START_KERNEL_map + _PAGE_TABLE_NOENC + pgtno = pgtno + 1 + .endr + /* 6 MB reserved space + a 2MB hole */ + .fill 4,8,0 NEXT_PAGE(level1_fixmap_pgt) + .rept (FIXMAP_PMD_NUM) .fill 512,8,0 + .endr #undef PMDS diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index e848a4811785..a927f5f39bee 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -637,6 +637,16 @@ void __native_set_fixmap(enum fixed_addresses idx, pte_t pte) { unsigned long address = __fix_to_virt(idx); +#ifdef CONFIG_X86_64 + /* + * In arch/x86/kernel/head_64.S, the static page table has + * been setup for fixmap. Add a sanity compiling check + * whether fixmap space has exceeded the capacity. + */ + BUILD_BUG_ON((__end_of_permanent_fixed_addresses + 511)/512 + > FIXMAP_PMD_NUM); +#endif + if (idx >= __end_of_fixed_addresses) { BUG(); return; diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c index 45b700ac5fe7..b0aa2364a3c6 100644 --- a/arch/x86/xen/mmu_pv.c +++ b/arch/x86/xen/mmu_pv.c @@ -1953,7 +1953,10 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) 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); - set_page_prot(level1_fixmap_pgt, PAGE_KERNEL_RO); + + for (i = 0; i < FIXMAP_PMD_NUM; i++) + set_page_prot(level1_fixmap_pgt + i * 512, + PAGE_KERNEL_RO); /* Pin down new L4 */ pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE, > > #1 would be preferred, but for a quick fix #2 is okay as well. > > Thanks, > > tglx >