From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753711AbcBZIPz (ORCPT ); Fri, 26 Feb 2016 03:15:55 -0500 Received: from mail-wm0-f42.google.com ([74.125.82.42]:35949 "EHLO mail-wm0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753438AbcBZIPy (ORCPT ); Fri, 26 Feb 2016 03:15:54 -0500 Subject: Re: BUG: unable to handle kernel paging request from pty_write [was: Linux 4.4.2] To: Peter Hurley , Greg KH , linux-kernel@vger.kernel.org, Andrew Morton , torvalds@linux-foundation.org, stable@vger.kernel.org References: <20160217203730.GA14820@kroah.com> <56CED373.9060603@suse.cz> <56CF4A83.3040408@hurleysoftware.com> Cc: lwn@lwn.net From: Jiri Slaby X-Enigmail-Draft-Status: N1110 Message-ID: <56D009B6.6000006@suse.cz> Date: Fri, 26 Feb 2016 09:15:50 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <56CF4A83.3040408@hurleysoftware.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/25/2016, 07:40 PM, Peter Hurley wrote: >> This was trigerred by a gdb build on our servers [1]. > > I noted that the crash is not strictly for building gdb but appears > to be with gdb running? Yes, when gdb is built, gdb tests are run. From the build log gdb_log [1], checks were run on the top of built gdb: ./orphanripper make -j8 -k check//unix/-m64 check//unix/-m64/-fPIC/-pie check//unix/-m32 check//unix/-m32/-fPIC/-pie [1] http://labs.suse.cz/jslaby/bug-968218/ > Perhaps some test that has failed? > Maybe some ABI violation with gdb + kvm? [ 425s] === gdb tests === [ 425s] [ 425s] Schedule of variations: [ 425s] unix/-m32 [ 425s] [ 425s] Running target unix/-m32 [ 425s] Using /usr/share/dejagnu/baseboards/unix.exp as board description file for target. [ 425s] Using /usr/share/dejagnu/config/unix.exp as generic interface file for target. [ 425s] Using /home/abuild/rpmbuild/BUILD/gdb-7.10.1/gdb/testsuite/config/unix.exp as tool-and-target-specific interface file. [ 425s] Running /home/abuild/rpmbuild/BUILD/gdb-7.10.1/gdb/testsuite/gdb.base/break-interp.exp ... [ 425s] [ 413.383880] kernel tried to execute NX-protected page - exploit attempt? (uid: 399) It's plenty of code run in there: https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=gdb/testsuite/gdb.base/break-interp.exp;h=713e1008fb3739f7fdcdb6c0a484a46b279ef1b6;hb=HEAD > Is this reproducible? I tried whole day yesterday without luck :(. thanks, -- js suse labs