From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760561AbXGCRdf (ORCPT ); Tue, 3 Jul 2007 13:33:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755632AbXGCRd2 (ORCPT ); Tue, 3 Jul 2007 13:33:28 -0400 Received: from tomts40.bellnexxia.net ([209.226.175.97]:62434 "EHLO tomts40-srv.bellnexxia.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754263AbXGCRd1 (ORCPT ); Tue, 3 Jul 2007 13:33:27 -0400 Date: Tue, 3 Jul 2007 13:33:24 -0400 From: Mathieu Desnoyers To: Frederik Deweerdt Cc: Alan Cox , akpm@osdl.org, linux-kernel@vger.kernel.org, Andi Kleen Subject: [PATCH] i386 CPA fix - do not free reserved pages Message-ID: <20070703173324.GA1461@Krystal> References: <20070703150656.4f618dd5@the-village.bc.nu> <20070703153747.GA28808@Krystal> <20070703162640.GA31909@slug> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <20070703162640.GA31909@slug> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 13:31:45 up 2 days, 12:14, 4 users, load average: 0.60, 0.64, 0.42 User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Right, there is a test missing, can you try this fix on top of my x86_64 mm cpa cache flush fix ? i386 CPA fix - do not free reserved pages We have to use the same conditions found in change_page_attr in global_tlb_flush regarding the conditions that leads to free the page. Signed-off-by: Mathieu Desnoyers --- arch/i386/mm/pageattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-2.6-lttng/arch/i386/mm/pageattr.c =================================================================== --- linux-2.6-lttng.orig/arch/i386/mm/pageattr.c 2007-07-03 13:25:48.000000000 -0400 +++ linux-2.6-lttng/arch/i386/mm/pageattr.c 2007-07-03 13:28:34.000000000 -0400 @@ -247,7 +247,7 @@ 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) + if (PageReserved(pg) || !cpu_has_pse || page_private(pg) != 0) continue; ClearPagePrivate(pg); __free_page(pg); * Frederik Deweerdt (deweerdt@free.fr) wrote: > On Tue, Jul 03, 2007 at 11:37:47AM -0400, Mathieu Desnoyers wrote: > > 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. > > > Hi Mathieu, > > I've tried the patch on rc6-mm1, but it doesn't seem to fix the > problem. From what I understood, the bad_page() is called on PG_reserved > being set (flags:0x00000400), not the lru pointer being not NULL or > PG_arch_1 being set. > > Regards, > Frederik > > > Signed-off-by: Mathieu Desnoyers > > CC: Andi Kleen > [...] > > 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: > [...] > > > 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 > > - > > 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