From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22479 invoked by alias); 7 Jun 2007 03:37:09 -0000 Received: (qmail 22472 invoked by uid 22791); 7 Jun 2007 03:37:08 -0000 X-Spam-Status: No, hits=-0.8 required=5.0 tests=AWL,BAYES_50,DK_POLICY_SIGNSOME X-Spam-Check-By: sourceware.org Received: from mga03.intel.com (HELO mga03.intel.com) (143.182.124.21) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 07 Jun 2007 03:37:04 +0000 Received: from azsmga001.ch.intel.com ([10.2.17.19]) by azsmga101.ch.intel.com with ESMTP; 06 Jun 2007 20:37:03 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.16,392,1175497200"; d="scan'208";a="236478687" Received: from orsmsx335.jf.intel.com ([10.22.226.40]) by azsmga001.ch.intel.com with ESMTP; 06 Jun 2007 20:37:03 -0700 Received: from orsmsx419.amr.corp.intel.com ([10.22.226.88]) by orsmsx335.jf.intel.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 6 Jun 2007 20:37:02 -0700 X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Subject: FW: [BUG] Fwd: segfault : modprobe dccp_probe/tcp_probe Date: Thu, 07 Jun 2007 03:37:00 -0000 Message-ID: <8A3E977AB3C24845947ADAAE0526E395024C7CA5@orsmsx419.amr.corp.intel.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [BUG] Fwd: segfault : modprobe dccp_probe/tcp_probe Thread-Index: AceomONGLH2FRU4RShOqd/BCqdnT2wAHDBKg From: "Keshavamurthy, Anil S" To: X-OriginalArrivalTime: 07 Jun 2007 03:37:02.0671 (UTC) FILETIME=[1CA8A5F0:01C7A8B5] X-IsSubscribed: yes Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2007-q2/txt/msg00507.txt.bz2 =20 FYI -----Original Message----- From: linux-kernel-owner@vger.kernel.org [mailto:linux-kernel-owner@vger.kernel.org] On Behalf Of Ian McDonald Sent: Wednesday, June 06, 2007 4:13 PM To: Chuck Ebbert Cc: Linux Kernel Mailing List; prasanna@in.ibm.com; ananth@in.ibm.com; Keshavamurthy, Anil S; David S. Miller; Patrick Andrieux; DCCP Mailing List; jbeulich@novell.com Subject: Re: [BUG] Fwd: segfault : modprobe dccp_probe/tcp_probe On 6/7/07, Chuck Ebbert wrote: > On 06/06/2007 04:47 PM, Ian McDonald wrote: > > Hi there, > > > > We've seen a report of a problem with dccp_probe as shown below. The > > user has also verified that it occurs in tcp_probe as well. This is on > > Dave Miller's tree but that currently tracks Linus' tree quite > > closely. I do note that it is around 2.6.22-rc2 timeframe so there is > > a possibility fixes may have gone in since. > > > > It faulted when it tried to write the breakpoint instruction into the > running kernel's executable code. Apparently the kernel code is now marked > read-only? > > Yes it would appear to be the case as user has CONFIG_DEBUG_RODATA set. Patrick - can you turn this off and retest? It's under Kernel Hacking, Write protect kernel read only data structures. The list of commits that I see around this are at: http://git.kernel.org/?p=3Dlinux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git &a=3Dsearch&h=3DHEAD&st=3Dcommit&s=3DDEBUG_RODATA I suspect it's probably one of the latter ones giving the timing. I guess there are a couple of solutions here - either make kprobes conflict with CONFIG_DEBUG_RODATA so you can do one or the other, or look into more detail what access kprobes need. Ian --=20 Web: http://wand.net.nz/~iam4/ Blog: http://iansblog.jandi.co.nz WAND Network Research Group - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/