From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f48.google.com (mail-pb0-f48.google.com [209.85.160.48]) by kanga.kvack.org (Postfix) with ESMTP id 834DF6B0268 for ; Sat, 9 Nov 2013 14:07:29 -0500 (EST) Received: by mail-pb0-f48.google.com with SMTP id mc17so1208722pbc.35 for ; Sat, 09 Nov 2013 11:07:29 -0800 (PST) Received: from psmtp.com ([74.125.245.149]) by mx.google.com with SMTP id dj3si10624649pbc.310.2013.11.09.11.07.27 for ; Sat, 09 Nov 2013 11:07:28 -0800 (PST) Received: from [192.168.178.21] ([85.177.156.93]) by mail.gmx.com (mrgmx103) with ESMTPSA (Nemesis) id 0M2L60-1VveET0jTA-00s85e for ; Sat, 09 Nov 2013 20:07:25 +0100 Message-ID: <527E87EA.8080700@gmx.de> Date: Sat, 09 Nov 2013 20:07:22 +0100 From: =?UTF-8?B?VG9yYWxmIEbDtnJzdGVy?= MIME-Version: 1.0 Subject: Re: [uml-devel] fuzz tested 32 bit user mode linux image hangs in radix_tree_next_chunk() References: <526696BF.6050909@gmx.de> <5266A698.10400@gmx.de> <5266B60A.1000005@nod.at> <52715AD1.7000703@gmx.de> <527AB23D.2060305@gmx.de> <527AB51B.1020005@nod.at> In-Reply-To: <527AB51B.1020005@nod.at> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Richard Weinberger Cc: Konstantin Khlebnikov , Linux Kernel , linux-fsdevel , "linux-mm@kvack.org" , UML devel On 11/06/2013 10:31 PM, Richard Weinberger wrote: > Am 06.11.2013 22:18, schrieb Toralf FA?rster: >> On 11/06/2013 05:06 PM, Konstantin Khlebnikov wrote: >>> In this case it must stop after scanning whole tree in line: >>> /* Overflow after ~0UL */ >>> if (!index) >>> return NULL; >>> >> >> A fresh current example with latest git tree shows that lines 769 and 770 do alternate : > > Can you please ask gdb for the value of offset? > > Thanks, > //richard > Still trying to get those values. One attempt to do that was to replace -O2 with -O0 in the Makefile, but that resulted into this error : LD kernel/built-in.o CC mm/memory.o In function a??zap_pmd_rangea??, inlined from a??zap_pud_rangea?? at mm/memory.c:1265:8, inlined from a??unmap_page_rangea?? at mm/memory.c:1290:8: mm/memory.c:1220:23: error: call to a??__compiletime_assert_1220a?? declared with attribute error: BUILD_BUG failed mm/memory.c: In function a??follow_page_maska??: mm/memory.c:1530:18: error: call to a??__compiletime_assert_1530a?? declared with attribute error: BUILD_BUG failed make[1]: *** [mm/memory.o] Error 1 make: *** [mm] Error 2 With -O1 it compiled at least. >> >> tfoerste@n22 ~/devel/linux $ sudo gdb /usr/local/bin/linux-v3.12-48-gbe408cd 16619 -n -batch -ex bt >> 0x08296a8c in radix_tree_next_chunk (root=0x25, iter=0x462e7c64, flags=12) at lib/radix-tree.c:770 >> 770 if (node->slots[offset]) >> #0 0x08296a8c in radix_tree_next_chunk (root=0x25, iter=0x462e7c64, flags=12) at lib/radix-tree.c:770 >> #1 0x080cc1fe in find_get_pages (mapping=0x462ad470, start=0, nr_pages=14, pages=0xc) at mm/filemap.c:844 >> #2 0x080d5d6a in pagevec_lookup (pvec=0x462e7cc8, mapping=0x25, start=37, nr_pages=37) at mm/swap.c:914 >> #3 0x080d615a in truncate_inode_pages_range (mapping=0x462ad470, lstart=0, lend=-1) at mm/truncate.c:241 >> #4 0x080d64ff in truncate_inode_pages (mapping=0x25, lstart=51539607589) at mm/truncate.c:358 >> >> >> >> >> tfoerste@n22 ~/devel/linux $ sudo gdb /usr/local/bin/linux-v3.12-48-gbe408cd 16619 -n -batch -ex bt >> radix_tree_next_chunk (root=0x28, iter=0x462e7c64, flags=18) at lib/radix-tree.c:769 >> 769 while (++offset < RADIX_TREE_MAP_SIZE) { >> #0 radix_tree_next_chunk (root=0x28, iter=0x462e7c64, flags=18) at lib/radix-tree.c:769 >> #1 0x080cc1fe in find_get_pages (mapping=0x462ad470, start=0, nr_pages=14, pages=0x12) at mm/filemap.c:844 >> #2 0x080d5d6a in pagevec_lookup (pvec=0x462e7cc8, mapping=0x28, start=40, nr_pages=40) at mm/swap.c:914 >> #3 0x080d615a in truncate_inode_pages_range (mapping=0x462ad470, lstart=0, lend=-1) at mm/truncate.c:241 >> #4 0x080d64ff in truncate_inode_pages (mapping=0x28, lstart=77309411368) at mm/truncate.c:358 >> #5 0x0825e388 in hostfs_evict_inode (inode=0x462ad3b8) at fs/hostfs/hostfs_kern.c:242 >> #6 0x0811a8df in evict (inode=0x462ad3b8) at fs/inode.c:549 >> >> > > -- MfG/Sincerely Toralf FA?rster pgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3 -- 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