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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT 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 08552C43441 for ; Thu, 8 Nov 2018 22:17:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC87420883 for ; Thu, 8 Nov 2018 22:17:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="zj/jYv4K" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BC87420883 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org 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 S1732234AbeKIHol (ORCPT ); Fri, 9 Nov 2018 02:44:41 -0500 Received: from mail.kernel.org ([198.145.29.99]:37774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730302AbeKIHok (ORCPT ); Fri, 9 Nov 2018 02:44:40 -0500 Received: from localhost (unknown [208.72.13.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4999420989; Thu, 8 Nov 2018 22:07:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541714829; bh=vaY++PS1SOI3w0J/Jj9jFa1p9O0EGwRVnkHIFHqEjZs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zj/jYv4K+2oXWC1FatRjceZZ+gwgvure3y6Ub/V61+D3FUmR6BIKbczYbdAv4qBNx tlMK1iq3VsToY1eiOFwAIar4CGB1I1SymIwI7wU66ywhznX24XT3pMZTfuUw0KAdou LCTQSi0pMzwFm1OSW+8eE6th1bQRU50hlTByXOEg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sasha Levin Subject: [PATCH 4.9 153/171] Revert "x86/mm: Expand static page table for fixmap space" Date: Thu, 8 Nov 2018 13:52:03 -0800 Message-Id: <20181108215137.868071598@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181108215127.257643509@linuxfoundation.org> References: <20181108215127.257643509@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ This reverts commit 3a8304b7ad2e291777e8499e39390145d932a2fd, which was upstream commit 05ab1d8a4b36ee912b7087c6da127439ed0a903e. Ben Hutchings writes: This backport is incorrect. The part that updated __startup_64() in arch/x86/kernel/head64.c was dropped, presumably because that function doesn't exist in 4.9. However that seems to be an essential of the fix. In 4.9 the startup_64 routine in arch/x86/kernel/head_64.S would need to be changed instead. I also found that this introduces new boot-time warnings on some systems if CONFIG_DEBUG_WX is enabled. So, unless someone provides fixes for those issues, I think this should be reverted for the 4.9 branch. Signed-off-by: Sasha Levin --- arch/x86/include/asm/fixmap.h | 10 ---------- arch/x86/include/asm/pgtable_64.h | 3 +-- arch/x86/kernel/head_64.S | 16 ++++------------ arch/x86/mm/pgtable.c | 9 --------- arch/x86/xen/mmu.c | 8 ++------ 5 files changed, 7 insertions(+), 39 deletions(-) --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -14,16 +14,6 @@ #ifndef _ASM_X86_FIXMAP_H #define _ASM_X86_FIXMAP_H -/* - * Exposed to assembly code for setting up initial page tables. Cannot be - * calculated in assembly code (fixmap entries are an enum), but is sanity - * checked in the actual fixmap C code to make sure that the fixmap is - * covered fully. - */ -#define FIXMAP_PMD_NUM 2 -/* fixmap starts downwards from the 507th entry in level2_fixmap_pgt */ -#define FIXMAP_PMD_TOP 507 - #ifndef __ASSEMBLY__ #include #include --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -13,14 +13,13 @@ #include #include #include -#include extern pud_t level3_kernel_pgt[512]; 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 * FIXMAP_PMD_NUM]; +extern pte_t level1_fixmap_pgt[512]; extern pgd_t init_level4_pgt[]; #define swapper_pg_dir init_level4_pgt --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -23,7 +23,6 @@ #include "../entry/calling.h" #include #include -#include #ifdef CONFIG_PARAVIRT #include @@ -494,20 +493,13 @@ NEXT_PAGE(level2_kernel_pgt) KERNEL_IMAGE_SIZE/PMD_SIZE) NEXT_PAGE(level2_fixmap_pgt) - .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; - pgtno = pgtno + 1 - .endr - /* 6 MB reserved space + a 2MB hole */ - .fill 4,8,0 + .fill 506,8,0 + .quad level1_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE + /* 8MB reserved for vsyscalls + a 2MB hole = 4 + 1 entries */ + .fill 5,8,0 NEXT_PAGE(level1_fixmap_pgt) - .rept (FIXMAP_PMD_NUM) .fill 512,8,0 - .endr #undef PMDS --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -536,15 +536,6 @@ void __native_set_fixmap(enum fixed_addr { unsigned long address = __fix_to_virt(idx); -#ifdef CONFIG_X86_64 - /* - * Ensure that the static initial page tables are covering the - * fixmap completely. - */ - BUILD_BUG_ON(__end_of_permanent_fixed_addresses > - (FIXMAP_PMD_NUM * PTRS_PER_PTE)); -#endif - if (idx >= __end_of_fixed_addresses) { BUG(); return; --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1936,7 +1936,7 @@ void __init xen_setup_kernel_pagetable(p * L3_k[511] -> level2_fixmap_pgt */ convert_pfn_mfn(level3_kernel_pgt); - /* L3_k[511][508-FIXMAP_PMD_NUM ... 507] -> level1_fixmap_pgt */ + /* L3_k[511][506] -> level1_fixmap_pgt */ convert_pfn_mfn(level2_fixmap_pgt); } /* We get [511][511] and have Xen's version of level2_kernel_pgt */ @@ -1970,11 +1970,7 @@ void __init xen_setup_kernel_pagetable(p 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); - - for (i = 0; i < FIXMAP_PMD_NUM; i++) { - set_page_prot(level1_fixmap_pgt + i * PTRS_PER_PTE, - PAGE_KERNEL_RO); - } + set_page_prot(level1_fixmap_pgt, PAGE_KERNEL_RO); /* Pin down new L4 */ pin_pagetable_pfn(MMUEXT_PIN_L4_TABLE,