Op 25-09-12 12:42, Eric W. Biederman schreef: > Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx> writes: > >> Hey, >> >> Op 25-09-12 09:05, Eric W. Biederman schreef: >>> Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx> wrote: >>> >>>> Hey, >>>> >>>> Op 25-09-12 05:39, Eric W. Biederman schreef: >>>>> Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx> writes: >>>>> >>>>>> This reverts commit ee3efa91e240f513898050ef305a49a653c8ed90. >>>>>> >>>>>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxx> >>>>>> >>>>>> My thread about the regression seemed to have been ignored, so I can >>>> only >>>>>> conclude nobody objects against a full revert of this patch. >>>>>> >>>>>> My testcase is simply booting through netboot with / and ~/nfs as >>>> separate >>>>>> nfs filesystems, then doing 'ls ~/nfs' followed by 'ls ~' in a >>>> gnome-terminal >>>>>> window, then I get: >>>>> Do I read your description correctly: Without using a bind mount you >>>>> have the same nfs filesystem mounted on / and on ~/nfs? >>>>> >>>>> Something is definitely off with your configuration but if to work >>>> you >>>>> need to move mount points around then that something seems much >>>> deeper >>>>> than the __d_unalias change. >>>>> >>>>> What filesystems do you have mounted where? >>>>> >>>> / is a nfs filesystem, ~/nfs is a different nfs filesystem. >>> Are both filesystems on the same server? >>> >>> Are the two filesystems distinct filesystem on the server? >>> >>> Unless there is duplication of something somewhere the d_unalias code should not trigger. >> They're both on the same physical filesystem on the server, but unique exports: >> /home/mlankhorst/nfs *(no_subtree_check,insecure,rw,all_squash,anonuid=1000,anongid=1000) >> /home/mlankhorst/kvm/quantal-amd64 *(no_subtree_check,insecure,rw,no_root_squash) > Modern NFS does some interesting things with disconnected roots and the > like. I don't think it should be connecting those two filesytems > together because there are no overlapping directories. > > I really don't get why using one filesystem causes confusion in the other. > >> Rootfs is mounted by the kernel itself, I used a custom init script to mount /lib/modules >> early on: >> >> mount -t nfs -o nolock,vers=3 192.168.1.128:/home/mlankhorst/nfs /home/mlankhorst/nfs && >> mkdir -p /lib/modules/$(uname -r)/kernel && >> mount --bind /home/mlankhorst/nfs/linux /lib/modules/$(uname -r)/kernel && >> ([ -f /lib/modules/$(uname -r)/modules.symbols ] || depmod) >> >> exec /sbin/init > Could you try the following patch? This should report what directories > cannot be renamed because one of them is a mount point and it gives some > real insight into what is going on. ls / __d_unalias: /dev -> /dev __d_unalias: /proc -> /proc __d_unalias: /sys -> /sys Backtrace with WARN_ON_ONCE on the if check, unsurprisingly __d_unalias was inlined: WARNING: at fs/dcache.c:2407 d_materialise_unique+0x3ee/0x490() Hardware name: 1215N Modules linked in: snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq parport_pc snd_timer snd_seq_device arc4 nouveau ppdev snd eeepc_wmi parport ath9k asus_wmi ttm mac80211 mxm_wmi i915 ath9k_common ath9k_hw drm_kms_helper drm ath soundcore cfg80211 snd_page_alloc video nfsd Pid: 1452, comm: ls Not tainted 3.6.0-rc4-patser+ #175 Call Trace: [<ffffffff8104907a>] warn_slowpath_common+0x7a/0xb0 [<ffffffff810490c5>] warn_slowpath_null+0x15/0x20 [<ffffffff8117d52e>] d_materialise_unique+0x3ee/0x490 [<ffffffff812477cb>] ? nfs_fhget+0x4db/0x5a0 [<ffffffff81242b00>] nfs_lookup+0x130/0x190 [<ffffffff8116ff68>] lookup_real+0x18/0x50 [<ffffffff811704e3>] __lookup_hash+0x33/0x40 [<ffffffff81708153>] lookup_slow+0x44/0xa8 [<ffffffff81172806>] path_lookupat+0x236/0x7e0 [<ffffffff81170702>] ? getname_flags+0x32/0x100 [<ffffffff8115870c>] ? kmem_cache_alloc+0xdc/0x260 [<ffffffff81170702>] ? getname_flags+0x32/0x100 [<ffffffff81172ddc>] do_path_lookup+0x2c/0xc0 [<ffffffff81175a14>] user_path_at_empty+0x54/0xa0 [<ffffffff81076f0d>] ? lg_local_unlock+0x3d/0x70 [<ffffffff8116a1a1>] ? cp_new_stat+0x111/0x130 [<ffffffff81175a6c>] user_path_at+0xc/0x10 [<ffffffff8116a3b5>] vfs_fstatat+0x35/0x60 [<ffffffff8116a3f9>] vfs_lstat+0x19/0x20 [<ffffffff8116a555>] sys_newlstat+0x15/0x30 [<ffffffff813924ce>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff817191a2>] system_call_fastpath+0x16/0x1b ~Maarten -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
