From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 17 Jul 2008 13:23:17 -0700 From: Andrew Morton Subject: Re: [Bugme-new] [Bug 11110] New: Core dumps do not include writable unmodified MAP_PRIVATE maps Message-Id: <20080717132317.96e73124.akpm@linux-foundation.org> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: linux-mm@kvack.org Cc: bugme-daemon@bugzilla.kernel.org, drow@false.org, Roland McGrath , Oleg Nesterov , Alan Cox , Neil Horman List-ID: (switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). On Thu, 17 Jul 2008 11:57:08 -0700 (PDT) bugme-daemon@bugzilla.kernel.org wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=11110 > > Summary: Core dumps do not include writable unmodified > MAP_PRIVATE maps > Product: Process Management > Version: 2.5 > KernelVersion: 2.6.26 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: Other > AssignedTo: process_other@kernel-bugs.osdl.org > ReportedBy: drow@false.org > CC: davem@davemloft.net > > > Latest working kernel version: Not sure. > Earliest failing kernel version: Been failing at least since April 2006. > Passed at some point previous to that, probably 2.4. > Distribution: Debian > Hardware Environment: x86_64 SMP > Software Environment: GDB testsuite > Problem Description: > > The test corefile.exp fails because it maps a file and then core dumps, > expecting the mapped contents to be in the core dump. The mapping is made with > these options: > > buf2 = (char *) mmap (0, MAPSIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, > 0); > > Any page that has been touched will be dumped, any unmodified page will not be. > > I've discussed this with David Miller a couple of times; last time I recall was > in January 2007. > > Steps to reproduce: > > Run coremaker from the GDB testsuite (attached). Load the core file into GDB > and try to print buf2. > Does anyone recall whether this is deliberate behaviour, or did we just goof? Thanks. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org