Re: [PATCH] NLM: Fix "kernel BUG at fs/lockd/host.c:417!" or".../host.c:283!"

From: Nick Bowler
Date: Mon Jan 24 2011 - 16:10:58 EST

On 2011-01-24 15:50 -0500, Chuck Lever wrote:
> Nick Bowler <nbowler@xxxxxxxxxxxxxxxx> reports:
> > We were just having some NFS server troubles, and my client machine
> > running 2.6.38-rc1+ (specifically, commit 2b1caf6ed7b888c95) crashed
> > hard (syslog output appended to this mail).
> I was able to reproduce this BUG on my client running 2.6.38-rc2
> from earlier today. Here is a proposed fix. I can't reproduce the
> BUG with this patch applied.
> However, my reproducer hit the BUG in nlmsvc_release_host(). Nick hit
> roughly the same BUG in nlmclnt_release_host(), which suggests his
> "client" was also acting as a server.

Yeah, there are NFS exports on the client machine as well; although
as nobody had them mounted (and due to the timing of the crash) I hadn't
considered them.

> The symptoms are similar enough that I believe this patch should be
> sufficient to address both cases.

I'll try the patch, but since I don't know how to reproduce the failure
(rebooting the server just to see if it crashes again isn't an option),
I'll have to take your word for it.

Nick Bowler, Elliptic Technologies (
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