From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:55762 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753707Ab1DKA10 (ORCPT ); Sun, 10 Apr 2011 20:27:26 -0400 Message-ID: <4DA24B38.2080100@cn.fujitsu.com> Date: Mon, 11 Apr 2011 08:28:40 +0800 From: Mi Jinlong To: "J. Bruce Fields" CC: NFS Subject: Re: [PATCH] nfsd4: set right access bmap when initializing lock stateid References: <4D90357D.3080604@cn.fujitsu.com> <20110329031804.GD2695@fieldses.org> <4D9154F3.20806@cn.fujitsu.com> <20110410162056.GB26233@fieldses.org> In-Reply-To: <20110410162056.GB26233@fieldses.org> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 J. Bruce Fields: > On Tue, Mar 29, 2011 at 11:41:39AM +0800, Mi Jinlong wrote: >> >> J. Bruce Fields: >>> On Mon, Mar 28, 2011 at 03:15:09PM +0800, Mi Jinlong wrote: >>>> >>>> Content-Type: text/plain; charset=ISO-2022-JP >>>> Content-Transfer-Encoding: 7bit >>> Thanks, Mi Jinlong, the analysis is helpful, but I don't think your fix >>> is right. >>> >>> I think the problem here is basically that the cleanup on exit from >>> nfsd4_lock() may have to deal with a lock stateid that is partially >>> initialized, in that everything has been setup except the stuff that's >>> done by get_lock_access(). >> You are right. >> >>> Maybe something like this?? But I'm not able to test right now. >>> >>> --b. >>> >>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c >>> index fbde6f7..9e8ef31 100644 >>> --- a/fs/nfsd/nfs4state.c >>> +++ b/fs/nfsd/nfs4state.c >>> @@ -397,10 +397,13 @@ static void unhash_generic_stateid(struct nfs4_stateid *stp) >>> >>> static void free_generic_stateid(struct nfs4_stateid *stp) >>> { >>> - int oflag = nfs4_access_bmap_to_omode(stp); >>> + int oflag; >>> >>> - nfs4_file_put_access(stp->st_file, oflag); >>> - put_nfs4_file(stp->st_file); >>> + if (stp->st_access_bmap) { >>> + nfs4_access_bmap_to_omode(stp); >> This line should be >> >> oflag = nfs4_access_bmap_to_omode(stp); >> >> otherwise, uninitialized oflag will be used at the next line. >> >> After this patch, kernel runs correctly! > > So you tested something like this?--b. Yes, I have test this patch again, that's OK. -- ---- thanks Mi Jinlong > > commit f93a86b66b1778ce698051b4ebfc228abccce956 > Author: J. Bruce Fields > Date: Mon Mar 28 15:15:09 2011 +0800 > > nfsd4: fix oops on lock failure > > Lock stateid's can have access_bmap 0 if they were only partially > initialized (due to a failed lock request); handle that case in > free_generic_stateid. > > ------------[ cut here ]------------ > kernel BUG at fs/nfsd/nfs4state.c:380! > invalid opcode: 0000 [#1] SMP > last sysfs file: /sys/kernel/mm/ksm/run > Modules linked in: nfs fscache md4 nls_utf8 cifs ip6table_filter ip6_tables ebtable_nat ebtables ipt_MASQUERADE iptable_nat nf_nat bridge stp llc nfsd lockd nfs_acl auth_rpcgss sunrpc ipv6 ppdev parport_pc parport pcnet32 mii pcspkr microcode i2c_piix4 BusLogic floppy [last unloaded: mperf] > > Pid: 1468, comm: nfsd Not tainted 2.6.38+ #120 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform > EIP: 0060:[] EFLAGS: 00010297 CPU: 0 > EIP is at nfs4_access_to_omode+0x1c/0x29 [nfsd] > EAX: ffffffff EBX: dd758120 ECX: 00000000 EDX: 00000004 > ESI: dd758120 EDI: ddfe657c EBP: dd54dde0 ESP: dd54dde0 > DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 > Process nfsd (pid: 1468, ti=dd54c000 task=ddc92580 task.ti=dd54c000) > Stack: > dd54ddf0 e24f19ca 00000000 ddfe6560 dd54de08 e24f1a5d dd758130 deee3a20 > ddfe6560 31270000 dd54df1c e24f52fd 0000000f dd758090 e2505dd0 0be304cf > dbb51d68 0000000e ddfe657c ddcd8020 dd758130 dd758128 dd7580d8 dd54de68 > Call Trace: > [] free_generic_stateid+0x1c/0x3e [nfsd] > [] release_lockowner+0x71/0x8a [nfsd] > [] nfsd4_lock+0x617/0x66c [nfsd] > [] ? nfsd_setuser+0x199/0x1bb [nfsd] > [] ? nfsd_setuser_and_check_port+0x65/0x81 [nfsd] > [] ? _cond_resched+0x8/0x1c > [] ? slab_pre_alloc_hook.clone.33+0x23/0x27 > [] ? kmem_cache_alloc+0x1a/0xd2 > [] ? __call_rcu+0xd7/0xdd > [] ? fh_verify+0x401/0x452 [nfsd] > [] ? nfsd4_encode_operation+0x52/0x117 [nfsd] > [] ? nfsd4_putfh+0x33/0x3b [nfsd] > [] ? nfsd4_delegreturn+0xd4/0xd4 [nfsd] > [] nfsd4_proc_compound+0x1ea/0x33e [nfsd] > [] nfsd_dispatch+0xd1/0x1a5 [nfsd] > [] svc_process_common+0x282/0x46f [sunrpc] > [] svc_process+0xdc/0xfa [sunrpc] > [] nfsd+0xd6/0x115 [nfsd] > [] ? nfsd_shutdown+0x24/0x24 [nfsd] > [] kthread+0x62/0x67 > [] ? kthread_worker_fn+0x114/0x114 > [] kernel_thread_helper+0x6/0x10 > Code: eb 05 b8 00 00 27 4f 8d 65 f4 5b 5e 5f 5d c3 83 e0 03 55 83 f8 02 89 e5 74 17 83 f8 03 74 05 48 75 09 eb 09 b8 02 00 00 00 eb 0b <0f> 0b 31 c0 eb 05 b8 01 00 00 00 5d c3 55 89 e5 57 56 89 d6 8d > EIP: [] nfs4_access_to_omode+0x1c/0x29 [nfsd] SS:ESP 0068:dd54dde0 > ---[ end trace 2b0bf6c6557cb284 ]--- > > The trace route is: > > -> nfsd4_lock() > -> if (lock->lk_is_new) { > -> alloc_init_lock_stateid() > > 3739: stp->st_access_bmap = 0; > > ->if (status && lock->lk_is_new && lock_sop) > -> release_lockowner() > -> free_generic_stateid() > -> nfs4_access_bmap_to_omode() > -> nfs4_access_to_omode() > > 380: BUG(); ***** > > This problem was introduced by 0997b173609b9229ece28941c118a2a9b278796e. > > Reported-by: Mi Jinlong > Tested-by: Mi Jinlong > Signed-off-by: J. Bruce Fields > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index fbde6f7..8e3c407 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -397,10 +397,13 @@ static void unhash_generic_stateid(struct nfs4_stateid *stp) > > static void free_generic_stateid(struct nfs4_stateid *stp) > { > - int oflag = nfs4_access_bmap_to_omode(stp); > + int oflag; > > - nfs4_file_put_access(stp->st_file, oflag); > - put_nfs4_file(stp->st_file); > + if (stp->st_access_bmap) { > + oflag = nfs4_access_bmap_to_omode(stp); > + nfs4_file_put_access(stp->st_file, oflag); > + put_nfs4_file(stp->st_file); > + } > kmem_cache_free(stateid_slab, stp); > } > >