From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from verein.lst.de ([213.95.11.210]:37938 "EHLO mail.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031467AbXD3JWL (ORCPT ); Mon, 30 Apr 2007 05:22:11 -0400 Date: Mon, 30 Apr 2007 11:22:00 +0200 From: Christoph Hellwig Subject: Re: utrace comments Message-ID: <20070430092200.GA15773@lst.de> References: <20061127165138.GA2991@lst.de> <20070430040213.BF9901801A4@magilla.sf.frob.com> <20070430090840.GB31397@infradead.org> <20070430091808.GA11345@flint.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070430091808.GA11345@flint.arm.linux.org.uk> Sender: linux-arch-owner@vger.kernel.org To: Christoph Hellwig , Roland McGrath , Christoph Hellwig , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org List-ID: On Mon, Apr 30, 2007 at 10:18:09AM +0100, Russell King wrote: > Roland's idea of single-stepping is that it *must* be supported by > hardware for utrace to use it. There are a number of architectures > which can only do single-stepping by modifying the text of the > program being single stepped. ARM is one such example. > > As such, even when utrace is complete, some architectures will never > support in-kernel single step with utrace. I believe Roland's idea > is to have single step supported on these via some vapourware userspace > library. Does the current arm ptrace code support single stepping in kernelspace? If yes we absolutely need to continue to support it. > I'd also like to see utrace become *optional* > for architectures to support, rather than as it currently stands as > a *mandatory* requirement when merged. No way we'd keep both the old ptrace mess and utrace in the same tree.