svn commit: r227549 - stable/7/sys/nfsclient

[Rick Macklem]

Mark Saad wrote:
> On Thu, Nov 17, 2011 at 1:36 PM, Alfred Perlstein <alfred at freebsd.org>
> wrote:
> > * Rick Macklem <rmacklem at uoguelph.ca> [111116 21:16] wrote:
> >> Alfred Perlstein wrote:
> >> > Rick, I have a question, what will happen if the
> >> > nfs_freesillyrename()
> >> > call happens when the mount is down? Will it block the
> >> > taskqueue_thread?
> >> >
> >> > If so, it might make more sense to make a taskqueue per mount
> >> > point.
> >> >
> >> > If not, excuse me. :-)
> >> >
> >> Well, all nfs_freesillyrename() does is a vrele() on the parent
> >> directory when the file node's use count has gone to 0.
> >> I can't think why that would do any RPC, so I don't see a problem?
> >> If you do see a problem with vrele() on the directory, please let
> >> me
> >> know.
> >>
> >> The problem this fixes is a LOR that would occur when the vrele()
> >> on
> >> the directory was done by the thread doing VOP_INACTIVE(), since it
> >> already has the file vnode lock and the vrele() was locking the
> >> parent
> >> directory. This could cause a fairly rare deadlock.
> >
> > Yes, I understand the VFS deadlock.
> >
> > I see, I didn't realize the call was against the directory,
> > thank you for explaining.
> >
> > -Alfred
> Rick
> Any chance this will make it back into 7.3-RELEASE and 7.4-RELEASE ?
> 
I'm relatively new to FreeBSD, but I've never heard of an MFC to a
Release branch. (As far as I know, if it ever happens, it's for a
serious errata or security issue.)

Unless I'm incorrect (someone please correct me if I'm wrong), the
answer would be no, rick.

> 
> --
> mark saad | nonesuch at longcount.org