From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f197.google.com (mail-qk0-f197.google.com [209.85.220.197]) by kanga.kvack.org (Postfix) with ESMTP id 898C16B05E4 for ; Wed, 2 Aug 2017 12:40:08 -0400 (EDT) Received: by mail-qk0-f197.google.com with SMTP id c2so24258426qkb.10 for ; Wed, 02 Aug 2017 09:40:08 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id l12si29156004qtl.544.2017.08.02.09.40.07 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 02 Aug 2017 09:40:07 -0700 (PDT) Date: Wed, 2 Aug 2017 18:40:01 +0200 From: Andrea Arcangeli Subject: Re: [PATCH] userfaultfd_zeropage: return -ENOSPC in case mm has gone Message-ID: <20170802164001.GF21775@redhat.com> References: <1501136819-21857-1-git-send-email-rppt@linux.vnet.ibm.com> <20170731122204.GB4878@dhcp22.suse.cz> <20170731133247.GK29716@redhat.com> <20170731134507.GC4829@dhcp22.suse.cz> <20170802123440.GD17905@rapoport-lnx> <20170802155522.GB21775@redhat.com> <20170802162248.GA3476@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170802162248.GA3476@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Mike Rapoport , Andrew Morton , "Dr. David Alan Gilbert" , Pavel Emelyanov , linux-mm , lkml , stable@vger.kernel.org On Wed, Aug 02, 2017 at 06:22:49PM +0200, Michal Hocko wrote: > ESRCH refers to "no such process". Strictly speaking userfaultfd code is > about a mm which is gone but that is a mere detail. In fact the owner of Well this whole issue about which retval, is about a mere detail in the first place, so I don't think you can discount all other mere details as irrelevant in the evaluation of a change to solve a mere detail. > But as I've said, this might be really risky to change. My impression > was that userfaultfd is not widely used yet and those can be fixed > easily but if that is not the case then we have to live with the current > ENOSPC. The only change would be for userfaultfd non cooperative mode, and CRIU is the main user of that. So I think it is up to Mike to decide, I'm fine either ways. I certainly agree ESRCH could be a slightly better fit, I only wanted to clarify it's not a 100% match either. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org