------------[ cut here ]------------
WARNING: at /build/buildd/linux-2.6.35/fs/inode.c:1259 generic_detach_inode+0x169/0x1b0()
Hardware name: VirtualBox
Modules linked in: isofs udf crc_itu_t binfmt_misc vboxvideo drm agpgart vboxsf snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq ppdev snd_timer snd_seq_device parport_pc snd vboxguest psmouse soundcore lp snd_page_alloc i2c_piix4 parport serio_raw floppy e1000
Pid: 15507, comm: mount.vboxsf Tainted: G        W   2.6.35-20-generic #29-Ubuntu
Call Trace:
 [<c014ac52>] warn_slowpath_common+0x72/0xa0
 [<c022c959>] ? generic_detach_inode+0x169/0x1b0
 [<c022c959>] ? generic_detach_inode+0x169/0x1b0
 [<c014aca2>] warn_slowpath_null+0x22/0x30
 [<c022c959>] generic_detach_inode+0x169/0x1b0
 [<c022d6d7>] generic_drop_inode+0x17/0x70
 [<c022c7dc>] iput+0x4c/0x60
 [<f8111510>] sf_read_super_26+0x3f0/0x850 [vboxsf]
 [<c0175802>] ? tick_dev_program_event+0x42/0x150
 [<c0151519>] ? irq_exit+0x39/0x70
 [<c05cf28b>] ? smp_apic_timer_interrupt+0x5b/0x8a
 [<c05c9095>] ? apic_timer_interrupt+0x31/0x38
 [<c0350d44>] ? sub_alloc+0x64/0x170
 [<c012ce18>] ? default_spin_lock_flags+0x8/0x10
 [<c05c86ff>] ? _raw_spin_lock_irqsave+0x2f/0x50
 [<c0351081>] ? ida_get_new_above+0x101/0x1b0
 [<c021a58d>] ? alloc_super+0x1d/0x1b0
 [<c0355ff9>] ? strlcpy+0x39/0x50
 [<c021b2b1>] ? sget+0x151/0x1a0
 [<c021a100>] ? set_anon_super+0x0/0xf0
 [<c021b3e4>] get_sb_nodev+0x44/0x80
 [<f8111031>] sf_get_sb+0x21/0x30 [vboxsf]
 [<f8111120>] ? sf_read_super_26+0x0/0x850 [vboxsf]
 [<c021af14>] vfs_kern_mount+0x74/0x1c0
 [<c022f4c3>] ? get_fs_type+0x33/0xb0
 [<c021b0be>] do_kern_mount+0x3e/0xe0
 [<c023263c>] do_mount+0x1dc/0x220
 [<c02326eb>] sys_mount+0x6b/0xa0
 [<c05c8c04>] syscall_call+0x7/0xb
---[ end trace 05c84a22889e6669 ]---