From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759615AbXGCPiA (ORCPT ); Tue, 3 Jul 2007 11:38:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756010AbXGCPhw (ORCPT ); Tue, 3 Jul 2007 11:37:52 -0400 Received: from tomts40.bellnexxia.net ([209.226.175.97]:47100 "EHLO tomts40-srv.bellnexxia.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754306AbXGCPhv (ORCPT ); Tue, 3 Jul 2007 11:37:51 -0400 Date: Tue, 3 Jul 2007 11:37:47 -0400 From: Mathieu Desnoyers To: Alan Cox Cc: akpm@osdl.org, linux-kernel@vger.kernel.org Subject: Re: 2.6.22-rc6-mm1 bad_page events. Message-ID: <20070703153747.GA28808@Krystal> References: <20070703150656.4f618dd5@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <20070703150656.4f618dd5@the-village.bc.nu> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 11:35:51 up 2 days, 10:18, 7 users, load average: 0.47, 1.16, 1.25 User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi Alan, I already sent a fix to Andrew and Andi for this (hrm, forget to CC lkml on the original message): x86_64 mm cpa cache flush fix X86_64 and i386 cpa cache flush fix: list_del the deferred list entries to poison their pointers. clear the flag for every page put in the list. Signed-off-by: Mathieu Desnoyers CC: Andi Kleen --- arch/i386/mm/pageattr.c | 3 ++- arch/x86_64/mm/pageattr.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) Index: linux-2.6-lttng/arch/i386/mm/pageattr.c =================================================================== --- linux-2.6-lttng.orig/arch/i386/mm/pageattr.c 2007-06-29 12:33:47.000000000 -0400 +++ linux-2.6-lttng/arch/i386/mm/pageattr.c 2007-06-29 12:35:45.000000000 -0400 @@ -245,10 +245,11 @@ spin_unlock_irq(&cpa_lock); flush_map(&l); list_for_each_entry_safe(pg, next, &l, lru) { + clear_bit(PG_arch_1, &pg->flags); + list_del(&pg->lru); if (page_private(pg) != 0) continue; ClearPagePrivate(pg); - clear_bit(PG_arch_1, &pg->flags); __free_page(pg); } } Index: linux-2.6-lttng/arch/x86_64/mm/pageattr.c =================================================================== --- linux-2.6-lttng.orig/arch/x86_64/mm/pageattr.c 2007-06-29 12:33:51.000000000 -0400 +++ linux-2.6-lttng/arch/x86_64/mm/pageattr.c 2007-06-29 12:34:57.000000000 -0400 @@ -235,10 +235,11 @@ flush_map(&l); list_for_each_entry_safe(pg, next, &l, lru) { + clear_bit(PG_arch_1, &pg->flags); + list_del(&pg->lru); if (page_private(pg) != 0) continue; ClearPagePrivate(pg); - clear_bit(PG_arch_1, &pg->flags); __free_page(pg); } } * Alan Cox (alan@lxorguk.ukuu.org.uk) wrote: > X86 32bit with lots of debug turned on I get this: > > > > Freeing unused kernel memory: 156k freed > Write protecting the kernel text: 1668k > Write protecting the kernel read-only data: 719k > Bad page state in process 'swapper' > page:c10000c0 flags:0x00000400 mapping:00000000 mapcount:0 count:0 > Trying to fix it up, but a reboot is needed > Backtrace: > [] bad_page+0x6c/0x100 > [] free_hot_cold_page+0x5d/0x140 > [] global_flush_tlb+0x112/0x130 > [] init_post+0xd/0xe0 > [] kernel_init+0x216/0x220 > [] schedule_tail+0x0/0xe0 > [] kernel_init+0x0/0x220 > [] kernel_init+0x0/0x220 > [] kernel_thread_helper+0x7/0x10 > ======================= > Hexdump: > 000: 00 06 00 00 01 00 00 00 ff ff ff ff 0f 00 00 00 > 010: 00 00 00 00 00 00 00 00 78 00 00 c1 b8 00 00 c1 > 020: 00 06 00 00 01 00 00 00 ff ff ff ff a7 03 00 00 > 030: 00 00 00 00 00 00 00 00 98 00 00 c1 d8 00 00 c1 > 040: 00 04 00 00 00 00 00 00 ff ff ff ff 00 00 00 00 > 050: 00 00 00 00 00 00 00 00 b8 00 00 c1 f8 00 00 c1 > 060: 00 06 00 00 01 00 00 00 ff ff ff ff 00 04 00 00 > 070: 00 00 00 00 00 00 00 00 d8 00 00 c1 18 01 00 c1 > 080: 00 06 00 00 01 00 00 00 ff ff ff ff 9c 03 00 00 > 090: 00 00 00 00 00 00 00 00 f8 00 00 c1 38 01 00 c1 > 0a0: 00 06 00 00 01 00 00 00 ff ff ff ff 00 04 00 00 > 0b0: 00 00 00 00 00 00 00 00 18 01 00 c1 58 01 00 c1 > - > 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/ > -- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68