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[66.55.73.32]) by mx.google.com with ESMTP id l144si4176297ywb.328.2019.06.17.01.00.05 for ; Mon, 17 Jun 2019 01:00:05 -0700 (PDT) Received-SPF: pass (google.com: domain of alastair@d-silva.org designates 66.55.73.32 as permitted sender) client-ip=66.55.73.32; Authentication-Results: mx.google.com; dkim=pass header.i=@d-silva.org header.s=201810a header.b=fpSn1Xtk; spf=pass (google.com: domain of alastair@d-silva.org designates 66.55.73.32 as permitted sender) smtp.mailfrom=alastair@d-silva.org Received: from mail2.nmnhosting.com (unknown [202.169.106.97]) by ushosting.nmnhosting.com (Postfix) with ESMTPS id 7DD8E2DC0032; Mon, 17 Jun 2019 04:00:04 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=d-silva.org; s=201810a; t=1560758404; bh=5QkXNKOOo0s2HTA34p3+KiFaxnv3E6XBHbEwuPKBFG0=; h=From:To:Cc:References:In-Reply-To:Subject:Date:From; b=fpSn1XtkYo6WrcCUGmOHOdZNywi1QvmzZY4+xl5VCZcWBCS6cuFJZ4Bg2jHTm2zY8 aYj0YNe/GRufQBNqq5+D7BZJoH7Dn8clBz8eWh+9DhApm6D2taMEl1kfnO2F6+Wwzb W/+P5ndUYX5vLbVjdyP/q4c9p8ZDU/KgUYY2gWgVt67XpYFuY/1smVdKIiqeVeDgUY IMScq2G8iC8m3NQohxE0YI6tBs4TWuMudkSBjYzWLTSC87fTJvMfpwG+q9IMGNH5mD RnVpWZi4IaX8NK6tE9+QSrU4P/kSXip/FRVYnW1+AJI3BwkbUp/NcXjaPLwWhKHsol FxRQytR6bvv3iqTI+YFo7MYLtaJKh+WxmAU8njIhyNQx79yOWxYve4SwKeNQp50dHu RxEim3BmKhIKnR2H4sLXR0ViD6QCTWOZdbrCXzx4MUJj28vB90o6g68qZ+X5iBAMpR mfAG+vFEnT6PnOIFxsOcp0U29z01riqSThlWBY5r9dZ8PSrP/9EBD5QuVH7KTn7am6 bkB1UUJzPncn528VAjWChGL3S00VbOCyChWhvdfQYd9EvR2H1LSd3hJS2fhgjPjAel GGjg9VwpTKbymgxG0K3NPax7j8K+tzKTYxHeuow6IFIG1vVdoXuMbECzFWtF7/Juz8 uTnUA0b1u27vtiMZkiQy2/TY= Received: from Hawking (ntp.lan [10.0.1.1]) (authenticated bits=0) by mail2.nmnhosting.com (8.15.2/8.15.2) with ESMTPSA id x5H800Al057250 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 17 Jun 2019 18:00:00 +1000 (AEST) (envelope-from alastair@d-silva.org) From: "Alastair D'Silva" To: "'Christoph Hellwig'" Cc: "'Peter Zijlstra'" , "'Andrew Morton'" , "'David Hildenbrand'" , "'Oscar Salvador'" , "'Michal Hocko'" , "'Pavel Tatashin'" , "'Wei Yang'" , "'Arun KS'" , "'Qian Cai'" , "'Thomas Gleixner'" , "'Ingo Molnar'" , "'Josh Poimboeuf'" , "'Jiri Kosina'" , "'Mukesh Ojha'" , "'Mike Rapoport'" , "'Baoquan He'" , "'Logan Gunthorpe'" , , , References: <20190617043635.13201-1-alastair@au1.ibm.com> <20190617043635.13201-6-alastair@au1.ibm.com> <20190617065921.GV3436@hirez.programming.kicks-ass.net> <20190617071527.GA14003@infradead.org> In-Reply-To: <20190617071527.GA14003@infradead.org> Subject: RE: [PATCH 5/5] mm/hotplug: export try_online_node Date: Mon, 17 Jun 2019 18:00:00 +1000 Message-ID: <068d01d524e2$aa6f3000$ff4d9000$@d-silva.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 16.0 Thread-Index: AQKozGZqZYmaEl7M6DfiQR95qivs4QHbD3aSAzdXr9kBRRd62QEU+eDhpLzIGCA= Content-Language: en-au X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.6.2 (mail2.nmnhosting.com [10.0.1.20]); Mon, 17 Jun 2019 18:00:00 +1000 (AEST) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > -----Original Message----- > From: Christoph Hellwig > Sent: Monday, 17 June 2019 5:15 PM > To: Alastair D'Silva > Cc: Peter Zijlstra ; Andrew Morton foundation.org>; David Hildenbrand ; Oscar Salvador > ; Michal Hocko ; Pavel Tatashin > ; Wei Yang ; > Arun KS ; Qian Cai ; Thomas Gleixner > ; Ingo Molnar ; Josh Poimboeuf > ; Jiri Kosina ; Mukesh Ojha > ; Mike Rapoport ; > Baoquan He ; Logan Gunthorpe > ; linux-mm@kvack.org; linux- > kernel@vger.kernel.org; linux-nvdimm@lists.01.org > Subject: Re: [PATCH 5/5] mm/hotplug: export try_online_node > > On Mon, Jun 17, 2019 at 05:05:30PM +1000, Alastair D'Silva wrote: > > On Mon, 2019-06-17 at 08:59 +0200, Peter Zijlstra wrote: > > > On Mon, Jun 17, 2019 at 02:36:31PM +1000, Alastair D'Silva wrote: > > > > From: Alastair D'Silva > > > > > > > > If an external driver module supplies physical memory and needs to > > > > expose > > > > > > Why would you ever want to allow a module to do such a thing? > > > > > > > I'm working on a driver for Storage Class Memory, connected via an > > OpenCAPI link. > > > > The memory is only usable once the card says it's OK to access it. > > And all that should go through our pmem APIs, not not directly poke into mm > internals. And if you still need core patches send them along with the actual > driver. I tried that, but I was getting crashes as the NUMA data structures for that node were not initialised. Calling this was required to prevent uninitialized accesses in the pmem library. -- Alastair D'Silva mob: 0423 762 819 skype: alastair_dsilva msn: alastair@d-silva.org blog: http://alastair.d-silva.org Twitter: @EvilDeece