From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25256 invoked by alias); 23 Jan 2015 14:35:58 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 25191 invoked by uid 89); 23 Jan 2015 14:35:51 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-2.7 required=5.0 tests=AWL,BAYES_00,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mga03.intel.com Received: from mga03.intel.com (HELO mga03.intel.com) (134.134.136.65) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 23 Jan 2015 14:35:49 +0000 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga103.jf.intel.com with ESMTP; 23 Jan 2015 06:31:32 -0800 X-ExtLoop1: 1 Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by fmsmga002.fm.intel.com with ESMTP; 23 Jan 2015 06:35:37 -0800 Received: from irsmsx104.ger.corp.intel.com ([169.254.5.229]) by IRSMSX152.ger.corp.intel.com ([169.254.6.43]) with mapi id 14.03.0195.001; Fri, 23 Jan 2015 14:35:36 +0000 From: "Metzger, Markus T" To: Jan Kratochvil , "palves@redhat.com" CC: "gdb-patches@sourceware.org" Subject: RE: x86_64-m32 internal error for multi-thread-step.exp [Re: [PATCH v10 06/28] btrace: change branch trace data structure] Date: Fri, 23 Jan 2015 16:33:00 -0000 Message-ID: References: <1389686678-9039-1-git-send-email-markus.t.metzger@intel.com> <1389686678-9039-7-git-send-email-markus.t.metzger@intel.com> <20150108204943.GA4851@host2.jankratochvil.net> <20150122163740.GA11113@host2.jankratochvil.net> In-Reply-To: Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-IsSubscribed: yes X-SW-Source: 2015-01/txt/msg00651.txt.bz2 > -----Original Message----- > From: Metzger, Markus T > Sent: Friday, January 23, 2015 8:46 AM > To: Jan Kratochvil > It looks like the is_kernel_addr heuristic gets it wrong for 32bit inferi= ors > on 64-bit systems. The heuristic checks whether the most significant bit > is set. On 64-bit systems, the kernel is loaded into the high 64-bit area > leaving the entire 32-bit address space to 32-bit processes. GDB checks > bit 31 since it is a 32-bit inferior. It should still check bit 63 since= it is a 64-bit > kernel. Does GDB even know that the 32-bit inferior is running on a 64-b= it > system? If we can fix that heuristic, it's just a matter of increasing the trace bu= ffer size - the trace is bigger on 32-bit systems. I get the pointer size of the inferior via gdbarch_ptr_bit(). Does GDB also know the pointer size of the kernel that runs the inferior? Thanks, Markus. Intel GmbH Dornacher Strasse 1 85622 Feldkirchen/Muenchen, Deutschland Sitz der Gesellschaft: Feldkirchen bei Muenchen Geschaeftsfuehrer: Christian Lamprechter, Hannes Schwaderer, Douglas Lusk Registergericht: Muenchen HRB 47456 Ust.-IdNr./VAT Registration No.: DE129385895 Citibank Frankfurt a.M. (BLZ 502 109 00) 600119052