Return-Path: linux-nfs-owner@vger.kernel.org Received: from bombadil.infradead.org ([198.137.202.9]:33110 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753217AbaIDRvd (ORCPT ); Thu, 4 Sep 2014 13:51:33 -0400 Date: Thu, 4 Sep 2014 10:51:32 -0700 From: Christoph Hellwig To: Jeff Layton Cc: linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, Christoph Hellwig , "J. Bruce Fields" , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 13/17] locks: remove i_have_this_lease check from __break_lease Message-ID: <20140904175132.GG16935@infradead.org> References: <1409834323-7171-1-git-send-email-jlayton@primarydata.com> <1409834323-7171-14-git-send-email-jlayton@primarydata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1409834323-7171-14-git-send-email-jlayton@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, Sep 04, 2014 at 08:38:39AM -0400, Jeff Layton wrote: > I think that the intent of this code was to ensure that a process won't > deadlock if it has one fd open with a lease on it and then breaks that > lease by opening another fd. In that case it'll treat the __break_lease > call as if it were non-blocking. > > This seems wrong -- the process could (for instance) be multithreaded > and managing different fds via different threads. I also don't see any > mention of this limitation in the (somewhat sketchy) documentation. > > Remove the check and the non-blocking behavior when i_have_this_lease > is true. This looks reasonable to me, but I'm always very worried about changing userspace exposed behavior..