From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6188 invoked by alias); 23 Feb 2006 12:40:04 -0000 Received: (qmail 6177 invoked by uid 22791); 23 Feb 2006 12:40:03 -0000 X-Spam-Status: No, hits=-2.6 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 23 Feb 2006 12:40:01 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.12.11/8.12.11) with ESMTP id k1NCdx88001596 for ; Thu, 23 Feb 2006 07:39:59 -0500 Received: from pobox.toronto.redhat.com (pobox.toronto.redhat.com [172.16.14.4]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id k1NCds118619 for ; Thu, 23 Feb 2006 07:39:54 -0500 Received: from touchme.toronto.redhat.com (IDENT:postfix@touchme.toronto.redhat.com [172.16.14.9]) by pobox.toronto.redhat.com (8.12.8/8.12.8) with ESMTP id k1NCds93018714 for ; Thu, 23 Feb 2006 07:39:54 -0500 Received: from ton.toronto.redhat.com (ton.toronto.redhat.com [172.16.14.15]) by touchme.toronto.redhat.com (Postfix) with ESMTP id E46198000E9 for ; Thu, 23 Feb 2006 07:39:53 -0500 (EST) Received: from ton.toronto.redhat.com (localhost.localdomain [127.0.0.1]) by ton.toronto.redhat.com (8.13.1/8.13.1) with ESMTP id k1NCdrJ5022644 for ; Thu, 23 Feb 2006 07:39:53 -0500 Received: (from fche@localhost) by ton.toronto.redhat.com (8.13.1/8.13.1/Submit) id k1NCdrEe022568; Thu, 23 Feb 2006 07:39:53 -0500 X-Authentication-Warning: ton.toronto.redhat.com: fche set sender to fche@redhat.com using -f To: systemtap@sources.redhat.com Subject: Re: [PATCH] Kprobes- robust fault handling for i386 References: <9FBCE015AF479F46B3B410499F3AE05BC4BF0C@pdsmsx405> <20060223085935.GA2473@in.ibm.com> From: fche@redhat.com (Frank Ch. Eigler) Date: Thu, 23 Feb 2006 12:40:00 -0000 In-Reply-To: <20060223085935.GA2473@in.ibm.com> Message-ID: User-Agent: Gnus/5.0808 (Gnus v5.8.8) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2006-q1/txt/msg00594.txt.bz2 Prasanna S Panchamukhi writes: > [...] As of now to fix the broken kprobes fault handling, here is the > patch. This is only for i386, once we freeze on this prototype, this > can be ported to other architectures. > > This patch provides proper kprobes fault handling, if a user-specified > pre/post handlers tries to access user address space, through > copy_from_user(), get_user() etc. [...] Is it correct that this patch enables only the first bullet in ? By the way, just for laughs, I tried systemtap on a hugemem x86 kernel. As probably expected, none of the user-space copy operations worked: in fact, many "succeeded" and returned null data. - FChE