From patchwork Fri Apr 26 16:38:02 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleg Nesterov X-Patchwork-Id: 239888 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 2ECFB2C0106 for ; Sat, 27 Apr 2013 02:41:40 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755893Ab3DZQlV (ORCPT ); Fri, 26 Apr 2013 12:41:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:1701 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751909Ab3DZQlU (ORCPT ); Fri, 26 Apr 2013 12:41:20 -0400 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r3QGexS4016975 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 26 Apr 2013 12:41:00 -0400 Received: from tranklukator.brq.redhat.com (dhcp-1-102.brq.redhat.com [10.34.1.102]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with SMTP id r3QGeutX017562; Fri, 26 Apr 2013 12:40:56 -0400 Received: by tranklukator.brq.redhat.com (nbSMTP-1.00) for uid 500 oleg@redhat.com; Fri, 26 Apr 2013 18:38:05 +0200 (CEST) Date: Fri, 26 Apr 2013 18:38:02 +0200 From: Oleg Nesterov To: "H. Peter Anvin" Cc: Ingo Molnar , Linus Torvalds , Cyrill Gorcunov , Peter Zijlstra , Thomas Gleixner , David Miller , "Theodore Ts'o" , Linux Kernel Mailing List , the arch/x86 maintainers , Network Development , "linux-ext4@vger.kernel.org" , Fr??d??ric Weisbecker Subject: [PATCH v2] x86: make DR*_RESERVED unsigned long Message-ID: <20130426163802.GA30351@redhat.com> References: <20130424072630.GB1780@gmail.com> <20130424170702.GA1867@redhat.com> <5178282D.9030902@zytor.com> <20130425144818.GA25921@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20130425144818.GA25921@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-Scanned-By: MIMEDefang 2.68 on 10.5.11.25 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org DR6_RESERVED and DR_CONTROL_RESERVED are used to clear the set bits in the "unsigned long" data, make them long to ensure that "&~" doesn't clear the upper bits. This is only cleanup, the usage of ~DR*_RESERVED is safe but doesn't look clean and the pattern is error prone. - do_debug: dr6 &= ~DR6_RESERVED; this also wrongly clears 32-63 bits. Fortunately these bits are reserved and must be zero. - ptrace_write_dr7: data &= ~DR_CONTROL_RESERVED; on __i386__ this mixes long/int but sizeof should be the same. Reported-by: Linus Torvalds Signed-off-by: Oleg Nesterov --- arch/x86/include/uapi/asm/debugreg.h | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/uapi/asm/debugreg.h b/arch/x86/include/uapi/asm/debugreg.h index 3c0874d..c0c1b89 100644 --- a/arch/x86/include/uapi/asm/debugreg.h +++ b/arch/x86/include/uapi/asm/debugreg.h @@ -15,7 +15,7 @@ are either reserved or not of interest to us. */ /* Define reserved bits in DR6 which are always set to 1 */ -#define DR6_RESERVED (0xFFFF0FF0) +#define DR6_RESERVED (0xFFFF0FF0UL) #define DR_TRAP0 (0x1) /* db0 */ #define DR_TRAP1 (0x2) /* db1 */ @@ -65,7 +65,7 @@ gdt or the ldt if we want to. I am not sure why this is an advantage */ #ifdef __i386__ -#define DR_CONTROL_RESERVED (0xFC00) /* Reserved by Intel */ +#define DR_CONTROL_RESERVED (0xFC00UL) /* Reserved by Intel */ #else #define DR_CONTROL_RESERVED (0xFFFFFFFF0000FC00UL) /* Reserved */ #endif