From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f70.google.com (mail-pl0-f70.google.com [209.85.160.70]) by kanga.kvack.org (Postfix) with ESMTP id DB44F6B0007 for ; Tue, 20 Mar 2018 07:33:29 -0400 (EDT) Received: by mail-pl0-f70.google.com with SMTP id f4-v6so949207plr.11 for ; Tue, 20 Mar 2018 04:33:29 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id e61-v6si1465299plb.190.2018.03.20.04.33.28 for (version=TLS1 cipher=AES128-SHA bits=128/128); Tue, 20 Mar 2018 04:33:28 -0700 (PDT) Date: Tue, 20 Mar 2018 12:33:26 +0100 From: Michal Hocko Subject: Re: [PATCH 3/4] mm/hmm: HMM should have a callback before MM is destroyed Message-ID: <20180320113326.GJ23100@dhcp22.suse.cz> References: <20180315183700.3843-1-jglisse@redhat.com> <20180315183700.3843-4-jglisse@redhat.com> <20180315154829.89054bfd579d03097b0f6457@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180315154829.89054bfd579d03097b0f6457@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: jglisse@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ralph Campbell , Evgeny Baskakov , Mark Hairgrove , John Hubbard On Thu 15-03-18 15:48:29, Andrew Morton wrote: > On Thu, 15 Mar 2018 14:36:59 -0400 jglisse@redhat.com wrote: > > > From: Ralph Campbell > > > > The hmm_mirror_register() function registers a callback for when > > the CPU pagetable is modified. Normally, the device driver will > > call hmm_mirror_unregister() when the process using the device is > > finished. However, if the process exits uncleanly, the struct_mm > > can be destroyed with no warning to the device driver. > > The changelog doesn't tell us what the runtime effects of the bug are. > This makes it hard for me to answer the "did Jerome consider doing > cc:stable" question. There is no upstream user of this code IIRC, so does it make sense to mark anything for stable trees? -- Michal Hocko SUSE Labs