Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755959Ab0G0JIY (ORCPT ); Tue, 27 Jul 2010 05:08:24 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:39220 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754108Ab0G0JIV (ORCPT ); Tue, 27 Jul 2010 05:08:21 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Tue, 27 Jul 2010 18:03:30 +0900 From: KAMEZAWA Hiroyuki To: dann frazier Cc: Hugh Dickins , linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, Rik van Riel , KOSAKI Motohiro , Nick Piggin , Mel Gorman , Minchan Kim , Ralf Baechle Subject: Re: ia64 hang/mca running gdb 'make check' Message-Id: <20100727180330.b6ecba7f.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100727071914.GB22945@lackof.org> References: <20100720173512.GF26783@ldl.fc.hp.com> <20100721105136.9d4440de.kamezawa.hiroyu@jp.fujitsu.com> <20100721030629.GA9987@lackof.org> <20100727071914.GB22945@lackof.org> Organization: FUJITSU Co. 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X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4423 Lines: 107 On Tue, 27 Jul 2010 01:19:15 -0600 dann frazier wrote: > On Tue, Jul 20, 2010 at 09:19:50PM -0700, Hugh Dickins wrote: > > On Tue, 20 Jul 2010, dann frazier wrote: > > > On Wed, Jul 21, 2010 at 10:51:36AM +0900, KAMEZAWA Hiroyuki wrote: > > > > On Tue, 20 Jul 2010 11:35:12 -0600 > > > > dann frazier wrote: > > > > > > > > > Debian's ia64 autobuilders have been experiencing system crashes while > > > > > trying to run the gdb test suite: > > > > > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=588574 > > > > > > > > > > I was able to reproduce this w/ the latest git tree, and bisected it > > > > > down to this commit, introduced in 2.6.32: > > > > > > > > > > commit 62eede62dafb4a6633eae7ffbeb34c60dba5e7b1 > > > > > Author: Hugh Dickins > > > > > Date: Mon Sep 21 17:03:34 2009 -0700 > > > > > > > > > > mm: ZERO_PAGE without PTE_SPECIAL > > > > > > > > > > Reinstate anonymous use of ZERO_PAGE to all architectures, not just to > > > > > those which __HAVE_ARCH_PTE_SPECIAL: as suggested by Nick Piggin. > > > > > > > > > > Contrary to how I'd imagined it, there's nothing ugly about this, just a > > > > > zero_pfn test built into one or another block of vm_normal_page(). > > > > > > > > > > But the MIPS ZERO_PAGE-of-many-colours case demands is_zero_pfn() and > > > > > my_zero_pfn() inlines. Reinstate its mremap move_pte() shuffling of > > > > > ZERO_PAGEs we did from 2.6.17 to 2.6.19? Not unless someone shouts for > > > > > that: it would have to take vm_flags to weed out some cases. > > > > > > > > > > fyi, I found this to not be reproducible on SLES11 SP1 (which is > > > > > 2.6.32-based). I compared the .configs and found that the relevant > > > > > difference is the PAGE_SIZE. It does not fail w/ 64KB pages, but > > > > > reliably fails w/ 16KB pages. > > > > > > > > > > > > > Sorry, I have no idea... > > > > Hmm, what is the address of empty_zero_page[] on your debian(16kb-page) ? > > > > > > > > > dannf@krebs:~$ grep empty_zero_page /boot/System.map-2.6.32-5-mckinley > > > a0000001008784c0 d __ksymtab_empty_zero_page > > > a000000100882688 d __kcrctab_empty_zero_page > > > a000000100884ca4 r __kstrtab_empty_zero_page > > > a000000100974000 D empty_zero_page > > > > Thanks a lot for reporting this, but I too have no idea yet. > > > > It is likely that the bug is not to be found in that 62eede62, but > > rather in one of the preceding patches to mm/memory.c which 62eede62 > > was extending to ia64 and other architectures without PTE_SPECIAL. > > > > I wonder, from looking at that gdb testsuite log, is it plausible > > that all these hangs/crashes occurred when writing out a coredump? > > Is that something you could check for us? or rule out the possibility. > > Yep, seems so. I've reduced it down to this test case: > > dannf@rx2600:~> cat > foo.c > int leaf(void) { > return 0; > } > > int main(void) { > leaf(); > } > dannf@rx2600:~> gcc -g foo.c -o foo > dannf@rx2600:~> gdb ./foo > GNU gdb (GDB) SUSE (7.0-0.4.16) > Copyright (C) 2009 Free Software Foundation, Inc. > License GPLv3+: GNU GPL version 3 or later > This is free software: you are free to change and redistribute it. > There is NO WARRANTY, to the extent permitted by law. Type "show copying" > and "show warranty" for details. > This GDB was configured as "ia64-suse-linux". > For bug reporting instructions, please see: > ... > Reading symbols from /home/dannf/foo...done. > (gdb) break leaf > Breakpoint 1 at 0x40000000000005c1: file foo.c, line 2. > (gdb) run > Starting program: /home/dannf/foo > Missing separate debuginfo for /lib/ld-linux-ia64.so.2 > Try: zypper install -C "debuginfo(build-id)=d5bfb8b5940e174d54b978ca515dc0df76c7618c" > Missing separate debuginfo for /lib/libc.so.6.1 > Try: zypper install -C "debuginfo(build-id)=ca78657bd9173653d95f8504a313d2b6db8cb1d6" > > Breakpoint 1, leaf () at foo.c:2 > 2 return 0; > (gdb) gcore /tmp/save > > [bang] > Does this happen on 2.6.34 or 2.6.35-rc kernel ? Thanks, -Kame -- 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/