Re: [NLM] 2.6.27.14 breakage when grace period expires

[Frank van Maarseveen <frankvm@frankvm.com>]

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On Thu, Feb 12, 2009 at 02:10:37PM -0500, Trond Myklebust wrote:
> On Thu, 2009-02-12 at 19:29 +0100, Frank van Maarseveen wrote:
> > On Thu, Feb 12, 2009 at 01:17:27PM -0500, Trond Myklebust wrote:
> > > On Thu, 2009-02-12 at 16:36 +0100, Frank van Maarseveen wrote:
> > > > A little theorizing:
> > > > If the unlock of a yet unrecovered lock has failed up to that point then
> > > > the client sure must remember the lock somehow. That might explain the
> > > > secondary error when a conflicting lock is granted by the server.
> > > 
> > > Sorry, but that doesn't hold water. The client will release the VFS
> > > 'mirror' of the lock before it attempts to unlock. Otherwise, you could
> > > have some nasty races between the unlock thread and the recovery
> > > thread...
> > > Besides, the granted callback handler on the client only checks the list
> > > of blocked locks for a match.
> > 
> > ok, then we have more than one NLM bug to resolve.
> > 
> > > 
> > > Oh, bugger, I know what this is... It's the same thing that happened to
> > > the NFSv4 callback server. If you compile with CONFIG_IPV6 or
> > > CONFIG_IPV6_MODULE enabled, and also set CONFIG_SUNRPC_REGISTER_V4, then
> > > the NLM server will listen on an IPv6 socket, and so the RPC request
> > > come in with their IPv4 address mapped into the IPv6 namespace.
> > 
> > Nope:
> > 
> > 	$ zgrep IPV6 /proc/config.gz 
> > 	# CONFIG_IPV6 is not set
> > 	$ zgrep SUNRPC /proc/config.gz 
> > 	CONFIG_SUNRPC=y
> > 	CONFIG_SUNRPC_GSS=y
> > 	# CONFIG_SUNRPC_BIND34 is not set
> 
> Sorry, yes... 2.6.27.x should be OK. The lockd v4mapped addresses bug is
> specific to 2.6.29. Chuck, are you planning on fixing this before
> 2.6.29-final comes out?
> 
> > And remember this is not a recent regression.
> 
> It would help if you sent us the full binary tcpdump, instead of just
> the summary. That should enable us to figure out which of the tests is
> failing in nlmclnt_grant().

I posted the link already. Anyway, see attachment.

-- 
Frank

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