From patchwork Thu Mar 16 15:33:32 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Garnier X-Patchwork-Id: 9628719 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1A5BF60244 for ; Thu, 16 Mar 2017 15:35:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0B5152864B for ; Thu, 16 Mar 2017 15:35:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F3BD828651; Thu, 16 Mar 2017 15:35:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id CF2B42864B for ; Thu, 16 Mar 2017 15:35:10 +0000 (UTC) Received: (qmail 9365 invoked by uid 550); 16 Mar 2017 15:35:07 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 9344 invoked from network); 16 Mar 2017 15:35:07 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=FlvMezFd0fIOgArrzoTxMnT3gFnRG92r6TdGDECewy4=; b=StWp14poA7h9A+MAE6P85SQdCvhgaHxk4BR2kmxV81+P0XbpxvTes3BEIAb17k/80a kQAMSuBmG/0pLmNSHvrJhWKIjmKhjVp6+V0AYYuoQnjL7y2wlWuRAPQfs/0sic9Hvo+X 6eeGaPCbxtuAgH3midmDX9PmCEovJDPi+5x3hRP03dvo3kOoFgUZS65ztC2fm519O5pb 6xnmr9Xgg2DOZr9dBR5SaJ8LW7VQATzXtEgPx/btD31pyMnI8wRjbazxahZaO7rflTDP lYSmfEGsydsafzQSBQnxeRDZK6s6c2AGGSYFX/1jnOjH2ksGB/K+YULocqPtBksNoo/k KnlQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=FlvMezFd0fIOgArrzoTxMnT3gFnRG92r6TdGDECewy4=; b=NrMY182asAPRWlJHr5cdq0I+2Ow59UTbaYc1T01nZa2MN7zZ3Z++BsYcvwzSNLTliu 85LVaYqTQ/9JsaXcotZrPFT/e1dCGvZHSUU5d275m2dikPvZx/XG3xoMEbruT1yPCqoj eMa+xDnLy2MFoLr1q/i1LMSvwO+HRVx3xZMhstpg+eaH1xs3oJffjbcprvCxb0HfA3uR v/cC85qdMbMlemGBJwWxZhupa4ZEPIQKlIYUje6vLyk4qZBcSVfKlF/t5vq7mBZI8BIO La7+VUQogfV163CFsCcu6+6BDdKxgPVxm3pR/qd2+1lLIN/OFZMDzH8oJfzYxk0JM0F5 KxDg== X-Gm-Message-State: AFeK/H2Mhb0e8qJWLbGVXAQ2LUf7VcAUt7tdxFDjrhjySXNCct+cqLdiYpkY+FYHis41b7m0/P3LmfK+vjN4aBXK X-Received: by 10.107.8.215 with SMTP id h84mr12328529ioi.134.1489678413500; Thu, 16 Mar 2017 08:33:33 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20170316081013.GB7815@gmail.com> References: <20170314170508.100882-1-thgarnie@google.com> <20170316081013.GB7815@gmail.com> From: Thomas Garnier Date: Thu, 16 Mar 2017 08:33:32 -0700 Message-ID: To: Ingo Molnar Cc: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Jonathan Corbet , Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Lorenzo Stoakes , Kees Cook , Juergen Gross , Andy Lutomirski , Paul Gortmaker , Andrew Morton , Michal Hocko , zijun_hu , Chris Wilson , Andy Lutomirski , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Jiri Kosina , Matt Fleming , Ard Biesheuvel , Boris Ostrovsky , Rusty Russell , Paolo Bonzini , Borislav Petkov , Christian Borntraeger , Frederic Weisbecker , "Luis R . Rodriguez" , Stanislaw Gruszka , Peter Zijlstra , Josh Poimboeuf , Vitaly Kuznetsov , Tim Chen , Joerg Roedel , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , "the arch/x86 maintainers" , LKML , linux-doc@vger.kernel.org, kasan-dev , Linux-MM , Linux PM list , linux-efi@vger.kernel.org, xen-devel@lists.xenproject.org, lguest@lists.ozlabs.org, kvm list , Kernel Hardening Subject: [kernel-hardening] Re: [PATCH v7 1/3] x86/mm: Adapt MODULES_END based on Fixmap section size X-Virus-Scanned: ClamAV using ClamSMTP On Thu, Mar 16, 2017 at 1:10 AM, Ingo Molnar wrote: > > Note that asm/fixmap.h is an x86-ism that isn't present in many other > architectures, so this hunk will break the build. > > To make progress with these patches I've fixed it up with an ugly #ifdef > CONFIG_X86, but it needs a real solution instead before this can be pushed > upstream. I also saw an error on x86 tip on special configuration. I found this new patch below to be a good solution to both. Let me know what you think. ===== This patch aligns MODULES_END to the beginning of the Fixmap section. It optimizes the space available for both sections. The address is pre-computed based on the number of pages required by the Fixmap section. It will allow GDT remapping in the Fixmap section. The current MODULES_END static address does not provide enough space for the kernel to support a large number of processors. Signed-off-by: Thomas Garnier --- Based on next-20170308 --- Documentation/x86/x86_64/mm.txt | 5 ++++- arch/x86/include/asm/pgtable_64.h | 1 + arch/x86/include/asm/pgtable_64_types.h | 3 ++- 3 files changed, 7 insertions(+), 2 deletions(-) diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt index 5724092db811..ee3f9c30957c 100644 --- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -19,7 +19,7 @@ ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space ... unused hole ... ffffffff80000000 - ffffffff9fffffff (=512 MB) kernel text mapping, from phys 0 -ffffffffa0000000 - ffffffffff5fffff (=1526 MB) module mapping space +ffffffffa0000000 - ffffffffff5fffff (=1526 MB) module mapping space (variable) ffffffffff600000 - ffffffffffdfffff (=8 MB) vsyscalls ffffffffffe00000 - ffffffffffffffff (=2 MB) unused hole @@ -39,6 +39,9 @@ memory window (this size is arbitrary, it can be raised later if needed). The mappings are not part of any other kernel PGD and are only available during EFI runtime calls. +The module mapping space size changes based on the CONFIG requirements for the +following fixmap section. + Note that if CONFIG_RANDOMIZE_MEMORY is enabled, the direct mapping of all physical memory, vmalloc/ioremap space and virtual memory map are randomized. Their order is preserved but their base will be offset early at boot time. diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 73c7ccc38912..67608d4abc2c 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -13,6 +13,7 @@ #include #include #include +#include extern pud_t level3_kernel_pgt[512]; extern pud_t level3_ident_pgt[512]; diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 3a264200c62f..bb05e21cf3c7 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -67,7 +67,8 @@ typedef struct { pteval_t pte; } pte_t; #endif /* CONFIG_RANDOMIZE_MEMORY */ #define VMALLOC_END (VMALLOC_START + _AC((VMALLOC_SIZE_TB << 40) - 1, UL)) #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) -#define MODULES_END _AC(0xffffffffff000000, UL) +/* The module sections ends with the start of the fixmap */ +#define MODULES_END __fix_to_virt(__end_of_fixed_addresses + 1) #define MODULES_LEN (MODULES_END - MODULES_VADDR) #define ESPFIX_PGD_ENTRY _AC(-2, UL) #define ESPFIX_BASE_ADDR (ESPFIX_PGD_ENTRY << PGDIR_SHIFT)