From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 8990 invoked by alias); 22 Feb 2016 16:19:50 -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 8970 invoked by uid 89); 22 Feb 2016 16:19:49 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.8 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy=Hx-languages-length:913, bps, watchpoints X-HELO: mailapp01.imgtec.com Received: from mailapp01.imgtec.com (HELO mailapp01.imgtec.com) (195.59.15.196) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 22 Feb 2016 16:19:48 +0000 Received: from hhmail02.hh.imgtec.org (unknown [10.100.10.20]) by Websense Email Security Gateway with ESMTPS id 05F36DE6829C0; Mon, 22 Feb 2016 16:19:44 +0000 (GMT) Received: from [10.100.200.149] (10.100.200.149) by hhmail02.hh.imgtec.org (10.100.10.21) with Microsoft SMTP Server id 14.3.266.1; Mon, 22 Feb 2016 16:19:45 +0000 Date: Mon, 22 Feb 2016 16:19:00 -0000 From: "Maciej W. Rozycki" To: Pedro Alves CC: Luis Machado , Subject: Re: [PATCH, v2] Expect SI_KERNEL or TRAP_BRKPT si_code values for MIPS breakpoint traps In-Reply-To: <56CB0A42.70507@redhat.com> Message-ID: References: <1456145829-5052-1-git-send-email-lgustavo@codesourcery.com> <56CB0A42.70507@redhat.com> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-SW-Source: 2016-02/txt/msg00657.txt.bz2 On Mon, 22 Feb 2016, Pedro Alves wrote: > I'd like to have a short paragraph in linux-nat.h about MIPS's behavior, > below the ppc comment. If you look at the x86 table above, which cases get > SI_KERNEL, and which don't? Single-step is not applicable, since the > MIPS doesn't handle single-stepping itself (IIRC), but do we also get > SI_KERNEL hardware bps and watchpoints, for example? As I previously noted the MIPS Linux port currently does not support hardware breakpoints even though hardware may have them implemented (they're optional). Only hardware watchpoints are supported right now. You are right in that there's no OS single-stepping support defined in the MIPS architecture and consequently Linux cannot support it on the MIPS target. Only JTAG single-stepping is possible with MIPS hardware. Maciej