From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tim Deegan Subject: Re: [PATCH 0 of 2] x86/mm: Unsharing ENOMEM handling Date: Thu, 15 Mar 2012 11:34:47 +0000 Message-ID: <20120315113447.GF4798@ocelot.phlegethon.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andres Lagar-Cavilla Cc: andres@gridcentric.ca, adin@gridcentric.ca, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org At 11:29 -0400 on 12 Mar (1331551776), Andres Lagar-Cavilla wrote: > These two patches were originally posted on Feb 15th as part of a larger > series. > > They were left to simmer as a discussion on wait queues took precedence. > > Regardless of the ultimate fate of wait queues, these two patches are necessary > as they solve some bugs on the memory sharing side. When unsharing fails, > domains would spin forever, hosts would crash, etc. > > The patches also clarify the semantics of unsharing, and comment how it's > handled. > > Two comments against the Feb 15th series taken care of here: > - We assert that the unsharing code can only return success or ENOMEN. > - Acked-by Tim Deegan added to patch #1 Applied, thanks. I'm a bit uneasy about the way this increases the amount of boilerplate and p2m-related knowledge that's needed at call sites, but it fixes real problems and I can't see an easy way to avoid it. Tim.