Re: [lkp] [nfsd] b44061d0b9: BUG: Dentry ffff880027d7c540{i=1846f,n=0a} still in use (1) [unmount of btrfs vda]

[Josef Bacik]

On 08/10/2016 02:06 PM, Linus Torvalds wrote:
> On Tue, Aug 9, 2016 at 10:39 PM, kernel test robot
> <xiaolong.ye@xxxxxxxxx> wrote:
> > [ 1537.558739] nfsd: last server has exited, flushing export cache
> > [ 1540.627795] BUG: Dentry ffff880027d7c540{i=1846f,n=0a}  still in use (1) [unmount of btrfs vda]
> > [ 1540.633915] ------------[ cut here ]------------
> > [ 1540.636551] WARNING: CPU: 0 PID: 20552 at fs/dcache.c:1474 umount_check+0x72/0x80
>
> Hmm. Adding Al and the btrfs people to the cc, and expanding the nfs
> list. Unlike the flakey-IO warning, this one sounds like a real issue.
> Whether it's some dentry leak by nfsd or a VFS or btrfs issue, I can't
> begin to guess. Al, ideas?
>
> More information in the original email on lkml.

I'm not subscribed to lkml and for some reason I can't find the original email 
in any of the lkml/linux-nfs archives.  Could you forward more of the details? 
Thanks,

Josef