From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752745AbdLHT71 (ORCPT ); Fri, 8 Dec 2017 14:59:27 -0500 Received: from mail.kernel.org ([198.145.29.99]:41166 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752374AbdLHT7Q (ORCPT ); Fri, 8 Dec 2017 14:59:16 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8BB9421920 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=luto@kernel.org From: Andy Lutomirski To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov , Brian Gerst , David Laight , Kees Cook , Peter Zijlstra , Andy Lutomirski Subject: [RFC PTI 2/3] Revert "x86/mm/pti: Disable native VSYSCALL" Date: Fri, 8 Dec 2017 11:59:10 -0800 Message-Id: X-Mailer: git-send-email 2.13.6 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This reverts commit 6a7b4041b853ecc653e2c1dda5b736ab5fd29357. With the PGD-propagation logic simplified, there's no need for this. --- arch/x86/Kconfig | 8 -------- 1 file changed, 8 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 411838058194..babb1e53b0a6 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2233,9 +2233,6 @@ choice config LEGACY_VSYSCALL_NATIVE bool "Native" - # The VSYSCALL page comes from the kernel page tables - # and is not available when PAGE_TABLE_ISOLATION is enabled. - depends on !PAGE_TABLE_ISOLATION help Actual executable code is located in the fixed vsyscall address mapping, implementing time() efficiently. Since @@ -2253,11 +2250,6 @@ choice exploits. This configuration is recommended when userspace still uses the vsyscall area. - When PAGE_TABLE_ISOLATION is enabled, the vsyscall area will become - unreadable. This emulation option still works, but PAGE_TABLE_ISOLATION - will make it harder to do things like trace code using the - emulation. - config LEGACY_VSYSCALL_NONE bool "None" help -- 2.13.6