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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 75DB5C433F5 for ; Fri, 7 Sep 2018 19:51:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C7FA20844 for ; Fri, 7 Sep 2018 19:51:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3C7FA20844 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.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 S1727657AbeIHAeL (ORCPT ); Fri, 7 Sep 2018 20:34:11 -0400 Received: from mga07.intel.com ([134.134.136.100]:61683 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725987AbeIHAeA (ORCPT ); Fri, 7 Sep 2018 20:34:00 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Sep 2018 12:51:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,343,1531810800"; d="scan'208";a="81760045" Received: from viggo.jf.intel.com (HELO localhost.localdomain) ([10.54.77.144]) by orsmga003.jf.intel.com with ESMTP; 07 Sep 2018 12:51:32 -0700 Subject: [RFC][PATCH 6/8] x86/mm: add vsyscall address helper To: linux-kernel@vger.kernel.org Cc: Dave Hansen , sean.j.christopherson@intel.com, peterz@infradead.org, tglx@linutronix.de, x86@kernel.org, luto@kernel.org From: Dave Hansen Date: Fri, 07 Sep 2018 12:49:01 -0700 References: <20180907194852.3C351B82@viggo.jf.intel.com> In-Reply-To: <20180907194852.3C351B82@viggo.jf.intel.com> Message-Id: <20180907194901.C54A0101@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Hansen We will shortly be using this check in two locations. Put it in a helper before we do so. Signed-off-by: Dave Hansen Cc: Sean Christopherson Cc: "Peter Zijlstra (Intel)" Cc: Thomas Gleixner Cc: x86@kernel.org Cc: Andy Lutomirski --- b/arch/x86/mm/fault.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff -puN arch/x86/mm/fault.c~is-vsyscall-addr arch/x86/mm/fault.c --- a/arch/x86/mm/fault.c~is-vsyscall-addr 2018-09-07 11:21:48.208751897 -0700 +++ b/arch/x86/mm/fault.c 2018-09-07 11:21:48.211751897 -0700 @@ -841,6 +841,15 @@ show_signal_msg(struct pt_regs *regs, un show_opcodes((u8 *)regs->ip, loglvl); } +/* + * The (legacy) vsyscall page is the long page in the kernel portion + * of the address space that has user-accessible permissions. + */ +static bool is_vsyscall_vaddr(unsigned long vaddr) +{ + return (vaddr & ~0xfff) == VSYSCALL_ADDR; +} + static void __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code, unsigned long address, u32 *pkey, int si_code) @@ -870,7 +879,7 @@ __bad_area_nosemaphore(struct pt_regs *r * emulation. */ if (unlikely((error_code & X86_PF_INSTR) && - ((address & ~0xfff) == VSYSCALL_ADDR))) { + is_vsyscall_vaddr(address))) { if (emulate_vsyscall(regs, address)) return; } _