From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Weber Date: Wed, 31 Jul 2013 14:19:34 +0200 Subject: [Ocfs2-devel] NULL pointer dereference in __ocfs2_claim_clusters In-Reply-To: <51F8E43E.5080303@oracle.com> References: <2093054.cfueY8DOT0@o3-3> <51F7816A.6050303@tao.ma> <51F8E43E.5080303@oracle.com> Message-ID: <5077941.ff0Qv5NFt0@o3-3> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Am Mittwoch, 31. Juli 2013, 18:17:34 schrieb Jeff Liu: > Hi Tao, > > On 07/30/2013 05:03 PM, Tao Ma wrote: > > Hi David, > > > > On 07/30/2013 03:14 PM, David Weber wrote: > >> Hi, > >> > >> we are currently trying to use OCFS2 in Linux 3.11.0-rc3 as a VM storage. > >> > >> When we try to discard free blocks from inside the guest we get a NULL > >> Pointer> > >> dereference on the host: > > I thought this is already fixed by Tiger about a year ago. > > https://oss.oracle.com/pipermail/ocfs2-devel/2012-September/008734.html > > would you mind trying this patch to see if it works? The patch works. There are no OOPS any more and according to shared-du the image shrank to the minimum size. Cheers, David > > This fix looks good to me. I'd like to rebase it on behalf of Tiger(as > Tiger has left Oracle last year) If you have no objections(i.e, Originally, > you also thought it might could be fixed by skipping the call of > ocfs2_readahead_for_cow if file = NULL should works), and then it need an > Acked-by from you as you're the author of the readahead for CoW. > > Thanks, > -Jeff > > > Thanks, > > Tao > > > >> [ 3452.936566] BUG: unable to handle kernel NULL pointer dereference at > >> 0000000000000020 > >> [ 3452.937042] IP: [] > >> ocfs2_duplicate_clusters_by_page+0x26/0x3cb [ocfs2] > >> [ 3452.937535] PGD 0 > >> [ 3452.937655] Oops: 0000 [#1] SMP > >> [ 3452.937853] Modules linked in: vhost_net vhost tun drbd ebtable_nat > >> ebtables ocfs2_stack_o2cb bridge stp llc kvm_intel kvm lru_cache dlm sctp > >> libcrc32c ocfs2_dlm ocfs2_dlmfs ocfs2 ocfs2_stackglue ocfs2_nodemanager > >> configfs igb [last unloaded: drbd] > >> [ 3452.939281] CPU: 0 PID: 3247 Comm: qemu-system-x86 Tainted: G > >> I > >> 3.11.0-rc3 #1 > >> [ 3452.939754] Hardware name: Supermicro X8DTU/X8DTU, BIOS 1.0c > >> 07/24/2009 [ 3452.940159] task: ffff88079df02620 ti: ffff88079162a000 > >> task.ti: ffff88079162a000 [ 3452.940601] RIP: 0010:[] > >> [] ocfs2_duplicate_clusters_by_page+0x26/0x3cb [ocfs2] > >> [ 3452.941232] RSP: 0018:ffff88079162b9d8 EFLAGS: 00010296 > >> [ 3452.941542] RAX: 00000000007e0101 RBX: ffff88079dd735c0 RCX: > >> 000000000001f8b7 [ 3452.941965] RDX: 0000000000000026 RSI: > >> 0000000000000000 RDI: ffff88079be98030 [ 3452.942389] RBP: > >> ffff88079162ba68 R08: 000000000001ad0a R09: 0000000000000001 [ > >> 3452.942836] R10: f84eb5df22f96c02 R11: 0000000000000000 R12: > >> 0000000000000001 > >> [ 3452.943266] R13: 000000000001f8b7 R14: 0000000000000026 R15: > >> 0000000000000001 > >> [ 3452.943687] FS: 00007f304b7fe700(0000) GS:ffff8807bfc00000(0000) > >> knlGS:0000000000000000 > >> [ 3452.944164] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > >> [ 3452.944500] CR2: 0000000000000020 CR3: 000000079171a000 CR4: > >> 00000000000027e0 > >> [ 3452.944920] Stack: > >> [ 3452.945032] ffff88079162bb80 ffff88079162bb84 ffff88079162ba68 > >> ffffffffa00fd4bc [ 3452.945485] 0000000000000000 ffff88079d3f6000 > >> ffff88079be98030 ffff88079bfd1ed8 [ 3452.945936] 000000000001f8b7 > >> 000000000001ad0a 0000000000000000 0000000000000000 > >> [ 3452.946388] Call Trace: > >> [ 3452.946535] [] ? __ocfs2_claim_clusters+0x1f7/0x325 > >> [ocfs2] [ 3452.946967] [] > >> ocfs2_replace_cow+0x3f0/0xe18 [ocfs2] [ 3452.947364] > >> [] ocfs2_refcount_cow+0x53f/0x668 [ocfs2] [ > >> 3452.947764] [] ocfs2_cow_file_pos+0x11c/0x123 > >> [ocfs2] [ 3452.948164] [] > >> ocfs2_remove_inode_range+0xc6/0xd5b [ocfs2] [ 3452.948593] > >> [] ? ocfs2_read_inode_block_full+0x36/0x55 [ocfs2] > >> [ 3452.949040] [] ? > >> ocfs2_inode_lock_full_nested+0x515/0xaa8 [ocfs2] > >> [ 3452.949503] [] ? ocfs2_extend_trans+0x1f9/0x1f9 > >> [ocfs2] [ 3452.949914] [] > >> __ocfs2_change_file_space+0x3d0/0xaa3 [ocfs2] [ 3452.950354] > >> [] ocfs2_fallocate+0x70/0x74 [ocfs2] [ 3452.950727] > >> [] do_fallocate+0x106/0x14d > >> [ 3452.951050] [] SyS_fallocate+0x47/0x6b > >> [ 3452.951368] [] system_call_fastpath+0x16/0x1b > >> [ 3452.951720] Code: ff 0f 0b 0f 0b 55 48 89 e5 41 57 41 56 41 55 41 54 > >> 53 48 83 ec 68 48 89 7d a0 48 89 75 90 41 89 d6 89 4d b0 44 89 45 b8 45 > >> 89 cf <48> 8b 46 20 48 89 45 98 48 89 c7 48 83 ef 48 e8 78 8e 02 00 49 > >> [ 3452.953241] RIP [] > >> ocfs2_duplicate_clusters_by_page+0x26/0x3cb [ocfs2] > >> [ 3452.953729] RSP > >> [ 3452.953931] CR2: 0000000000000020 > >> [ 3453.019391] ---[ end trace 08f73908d0d596c1 ]--- > >> > >> The filesystem was created with: > >> mkfs.ocfs2 -b 4K -C 1M -J block64 -L kvm-images -T vmstore /dev/drbd0 > >> > >> alice ocfs2 # gdb suballoc.o > >> GNU gdb (Gentoo 7.5.1 p2) 7.5.1 > >> Copyright (C) 2012 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 "x86_64-pc-linux-gnu". > >> For bug reporting instructions, please see: > >> ... > >> Reading symbols from /usr/src/linux-3.11-rc3/fs/ocfs2/suballoc.o...done. > >> (gdb) list *(__ocfs2_claim_clusters+0x1f7) > >> 0x40bc is in __ocfs2_claim_clusters (fs/ocfs2/suballoc.c:2306). > >> 2301 && ac->ac_which != OCFS2_AC_USE_MAIN); > >> 2302 > >> 2303 if (ac->ac_which == OCFS2_AC_USE_LOCAL) { > >> 2304 WARN_ON(min_clusters > 1); > >> 2305 > >> 2306 status = ocfs2_claim_local_alloc_bits(osb, > >> 2307 handle, > >> 2308 ac, > >> 2309 > >> bits_wanted, > >> 2310 > >> cluster_start, > >> > >> Qemu version: 1.5.2 > >> Guest OS: Ubuntu 13.10 snapshot (Linux 3.10) > >> Guest filesystem: ext4 > >> Command run on the guest: 'fstrim -v /' > >> > >> The disk configuration in libvirt looks like this: > >> > >> > >> > >> > >> > >>
> >> > >> > >> > >> and maps to such a qemu command line > >> > >> -device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x4 -drive file=/mnt/kvm- > >> images/ubuntu2.img,if=none,id=drive- > >> scsi0-0-0-0,format=raw,cache=none,discard=unmap -device scsi- > >> hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive- > >> scsi0-0-0-0,id=scsi0-0-0-0,bootindex=1 > >> > >> Thanks in advance! > >> > >> Cheers, > >> David > >> > >> > >> _______________________________________________ > >> Ocfs2-devel mailing list > >> Ocfs2-devel at oss.oracle.com > >> https://oss.oracle.com/mailman/listinfo/ocfs2-devel > > > > _______________________________________________ > > Ocfs2-devel mailing list > > Ocfs2-devel at oss.oracle.com > > https://oss.oracle.com/mailman/listinfo/ocfs2-devel