[11684.091468] ------------[ cut here ]------------
[11684.091476] WARNING: CPU: 0 PID: 4149 at /build/buildd/linux-3.13.0/fs/inode.c:282 drop_nlink+0x3e/0x50()
[11684.091477] Modules linked in: veth xt_addrtype xt_conntrack iptable_filter ipt_MASQUERADE iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack ip_tables x_tables bridge stp llc aufs snd_hda_intel snd_hda_codec snd_hwdep qxl snd_pcm snd_page_alloc psmouse serio_raw snd_timer ttm drm_kms_helper snd drm i2c_piix4 soundcore lp parport mac_hid btrfs xor raid6_pq libcrc32c floppy
[11684.091499] CPU: 0 PID: 4149 Comm: git Tainted: G        W    3.13.0-24-generic #46-Ubuntu
[11684.091500] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[11684.091502]  0000000000000009 ffff880000667cc0 ffffffff81715a64 0000000000000000
[11684.091504]  ffff880000667cf8 ffffffff810676bd ffff8800207afb50 ffff8800207afb50
[11684.091505]  0000000000000000 ffff88000bc85328 ffff88001c548900 ffff880000667d08
[11684.091507] Call Trace:
[11684.091512]  [<ffffffff81715a64>] dump_stack+0x45/0x56
[11684.091515]  [<ffffffff810676bd>] warn_slowpath_common+0x7d/0xa0
[11684.091516]  [<ffffffff8106779a>] warn_slowpath_null+0x1a/0x20
[11684.091518]  [<ffffffff811d408e>] drop_nlink+0x3e/0x50
[11684.091525]  [<ffffffffa029224c>] au_whtmp_rmdir+0x18c/0x1a0 [aufs]
[11684.091527]  [<ffffffff811d004b>] ? dentry_kill+0x1bb/0x270
[11684.091531]  [<ffffffffa029152e>] ? au_whtmp_ren+0x6e/0xc0 [aufs]
[11684.091535]  [<ffffffffa029f74c>] aufs_rmdir+0x25c/0x400 [aufs]
[11684.091538]  [<ffffffff811c5f88>] vfs_rmdir+0xa8/0x100
[11684.091540]  [<ffffffff811c97b1>] do_rmdir+0x1c1/0x1e0
[11684.091544]  [<ffffffff81020d35>] ? syscall_trace_enter+0x145/0x250
[11684.091546]  [<ffffffff811ca856>] SyS_rmdir+0x16/0x20
[11684.091548]  [<ffffffff8172663f>] tracesys+0xe1/0xe6
[11684.091549] ---[ end trace e0753656775c146f ]---
[11684.128348] aufs au_new_inode:432:git[4149]: Warning: Un-notified UDBA or repeatedly renamed dir, b0, btrfs, test_var_blending, hi465551, i501.