From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id AC4506B0207 for ; Fri, 2 Apr 2010 03:00:56 -0400 (EDT) Received: from il27vts01 (il27vts01.cig.mot.com [10.17.196.85]) by mdgate2.corp.mot.com (8.14.3/8.14.3) with SMTP id o3270iNf027709 for ; Fri, 2 Apr 2010 01:00:44 -0600 (MDT) Received: from mail-gw0-f54.google.com (mail-gw0-f54.google.com [74.125.83.54]) by mdgate2.corp.mot.com (8.14.3/8.14.3) with ESMTP id o326xZ6r027494 (version=TLSv1/SSLv3 cipher=RC4-MD5 bits=128 verify=OK) for ; Fri, 2 Apr 2010 01:00:44 -0600 (MDT) Received: by mail-gw0-f54.google.com with SMTP id a20so423405gwa.27 for ; Fri, 02 Apr 2010 00:00:53 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <20100402140406.d3d7f18e.kamezawa.hiroyu@jp.fujitsu.com> Date: Fri, 2 Apr 2010 15:00:52 +0800 Message-ID: Subject: Re: [Question] race condition in mm/page_alloc.c regarding page->lru? From: TAO HU Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: KAMEZAWA Hiroyuki , TAO HU , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Ye Yuan.Bo-A22116" , Chang Qing-A21550 , linux-arm-kernel@lists.infradead.org List-ID: Hi, kamezawa hiroyu Thanks for the hint! Hi, Minchan Kim Sorry. Not exactly sure your idea about . Below is a result of $ grep -n -r "list_del(&page->lru)" * in our src tree arch/s390/mm/pgtable.c:83: list_del(&page->lru); arch/s390/mm/pgtable.c:226: list_del(&page->lru); arch/x86/mm/pgtable.c:60: list_del(&page->lru); drivers/xen/balloon.c:154: list_del(&page->lru); drivers/virtio/virtio_balloon.c:143: list_del(&page->lru); fs/cifs/file.c:1780: list_del(&page->lru); fs/btrfs/extent_io.c:2584: list_del(&page->lru); fs/mpage.c:388: list_del(&page->lru); include/linux/mm_inline.h:37: list_del(&page->lru); include/linux/mm_inline.h:47: list_del(&page->lru); kernel/kexec.c:391: list_del(&page->lru); kernel/kexec.c:711: list_del(&page->lru); mm/migrate.c:69: list_del(&page->lru); mm/migrate.c:695: list_del(&page->lru); mm/hugetlb.c:467: list_del(&page->lru); mm/hugetlb.c:509: list_del(&page->lru); mm/hugetlb.c:836: list_del(&page->lru); mm/hugetlb.c:844: list_del(&page->lru); mm/hugetlb.c:900: list_del(&page->lru); mm/hugetlb.c:1130: list_del(&page->lru); mm/hugetlb.c:1809: list_del(&page->lru); mm/vmscan.c:597: list_del(&page->lru); mm/vmscan.c:1148: list_del(&page->lru); mm/vmscan.c:1246: list_del(&page->lru); mm/slub.c:827: list_del(&page->lru); mm/slub.c:1249: list_del(&page->lru); mm/slub.c:1263: list_del(&page->lru); mm/slub.c:2419: list_del(&page->lru); mm/slub.c:2809: list_del(&page->lru); mm/readahead.c:65: list_del(&page->lru); mm/readahead.c:100: list_del(&page->lru); mm/page_alloc.c:532: list_del(&page->lru); mm/page_alloc.c:679: list_del(&page->lru); mm/page_alloc.c:741: list_del(&page->lru); mm/page_alloc.c:820: list_del(&page->lru); mm/page_alloc.c:1107: list_del(&page->lru); mm/page_alloc.c:4784: list_del(&page->lru); On Fri, Apr 2, 2010 at 1:15 PM, Minchan Kim wrote: > On Fri, Apr 2, 2010 at 2:04 PM, KAMEZAWA Hiroyuki > wrote: >> On Fri, 2 Apr 2010 11:51:33 +0800 >> TAO HU wrote: >> >>> 2 patches related to page_alloc.c were applied. >>> Does anyone see a connection between the 2 patches and the panic? >>> NOTE: the full patches are attached. >>> >> >> I don't think there are relationship between patches and your panic. >> >> BTW, there is other case about the backlog rather than race in alloc_pages() >> itself. If someone list_del(&page->lru) and the page is already freed, >> you'll see the same backlog later. >> Then, I doubt use-after-free case rather than complicated races. > > It does make sense. > Please, grep "page handling" by out-of-mainline code. > If you found out, Please, post it. > > -- > Kind regards, > Minchan Kim > -- 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