From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753589AbdKIRa7 (ORCPT ); Thu, 9 Nov 2017 12:30:59 -0500 Received: from terminus.zytor.com ([65.50.211.136]:57763 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751066AbdKIRay (ORCPT ); Thu, 9 Nov 2017 12:30:54 -0500 Date: Thu, 9 Nov 2017 09:25:06 -0800 From: "tip-bot for Kirill A. Shutemov" Message-ID: Cc: keescook@chromium.org, akpm@linux-foundation.org, mhocko@suse.com, mingo@kernel.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, hpa@zytor.com, npiggin@gmail.com, kirill.shutemov@linux.intel.com Reply-To: kirill.shutemov@linux.intel.com, linux-kernel@vger.kernel.org, hpa@zytor.com, npiggin@gmail.com, mhocko@suse.com, tglx@linutronix.de, mingo@kernel.org, keescook@chromium.org, akpm@linux-foundation.org In-Reply-To: <20171107103804.47341-1-kirill.shutemov@linux.intel.com> References: <20171107103804.47341-1-kirill.shutemov@linux.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86/mm: Fix ELF_ET_DYN_BASE for 5-level paging Git-Commit-ID: be739f4b5ddece74ef25e2304b17a7fd24575e9b X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: be739f4b5ddece74ef25e2304b17a7fd24575e9b Gitweb: https://git.kernel.org/tip/be739f4b5ddece74ef25e2304b17a7fd24575e9b Author: Kirill A. Shutemov AuthorDate: Tue, 7 Nov 2017 13:38:04 +0300 Committer: Thomas Gleixner CommitDate: Thu, 9 Nov 2017 18:20:20 +0100 x86/mm: Fix ELF_ET_DYN_BASE for 5-level paging On machines with 5-level paging we don't want to allocate mapping above 47-bit unless user explicitly asked for it. See b569bab78d8d ("x86/mm: Prepare to expose larger address space to userspace") for details. c715b72c1ba4 ("mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changes") broke the behaviour. After the commit elf binary and heap got mapped above 47-bits. Use DEFAULT_MAP_WINDOW instead of TASK_SIZE to determine ELF_ET_DYN_BASE so it's forced to be below 47-bits unconditionally. Fixes: c715b72c1ba4 ("mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changes") Signed-off-by: Kirill A. Shutemov Signed-off-by: Thomas Gleixner Acked-by: Michal Hocko Cc: Kees Cook Cc: Nicholas Piggin Cc: linux-mm@kvack.org Cc: Andrew Morton Link: https://lkml.kernel.org/r/20171107103804.47341-1-kirill.shutemov@linux.intel.com --- arch/x86/include/asm/elf.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index c1a125e4..3a091ce 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -253,7 +253,7 @@ extern int force_personality32; * space open for things that want to use the area for 32-bit pointers. */ #define ELF_ET_DYN_BASE (mmap_is_ia32() ? 0x000400000UL : \ - (TASK_SIZE / 3 * 2)) + (DEFAULT_MAP_WINDOW / 3 * 2)) /* This yields a mask that user programs can use to figure out what instruction set this CPU supports. This could be done in user space,