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Subject: Re: RCU-isms in fs/nfs/delegation.c
From: Trond Myklebust <Trond.Myklebust@netapp.com>
To: David Howells <dhowells@redhat.com>
Cc: paulmck@linux.vnet.ibm.com, linux-nfs@vger.kernel.org,
       linux-kernel@vger.kernel.org
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On Tue, 2010-04-20 at 09:48 +0100, David Howells wrote: 
> Trond Myklebust <Trond.Myklebust@netapp.com> wrote:
> 
> > +		nfs_inode_set_delegation(inode, cred, res);
> > +	}
> > +out:
> > +	rcu_read_unlock();
> >  }
> 
> I think this is wrong.  nfs_inode_set_delegation() may sleep as it calls
> kmalloc() with GFP_KERNEL - but you still have the RCU read lock held.  I
> think you need to drop the RCU read lock before calling it.
> 
> David

Agreed. Thanks for the review...

Cheers
  Trond