Re: Problem during implementing NFS support

[David Woodhouse <dwmw2@infradead.org>]

On Mon, 2008-07-21 at 01:06 +0530, Balaji Rao wrote:
> The idea of the patch seems correct to me, that once we "own" the
> lock, an attempt to take it again should be a nop.

Well, kind of correct. There are potentially race conditions with the
handling of f->readdir_process, but given that we only ever really
compare it to 'current', it's actually going to turn out OK in practice.
You won't ever actually get a false negative (and deadlock) or a false
positive (and go through lookup() without locking), as far as I can
tell.

But still, it's ugly as sin and I'd much rather come up with a _proper_
fix in the VFS. I was looking at it at one point, and didn't actually
apply that patch to the JFFS2 tree.

Since general btrfs work is now more of a priority for me than getting
JFFS2 to be NFS-exportable was, I think I'll pick up where I left off
with that.

In the meantime, we have an evil hack which at least ought to work for
now.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse@intel.com                              Intel Corporation

-- 
dwmw2