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[2001:8b0:10b:1231::1]) by mx.google.com with ESMTPS id i15si15167570jan.87.2019.06.16.23.59.39 for (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Sun, 16 Jun 2019 23:59:39 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of peterz@infradead.org designates 2001:8b0:10b:1231::1 as permitted sender) client-ip=2001:8b0:10b:1231::1; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=merlin.20170209 header.b=ztpYbwNu; spf=pass (google.com: best guess record for domain of peterz@infradead.org designates 2001:8b0:10b:1231::1 as permitted sender) smtp.mailfrom=peterz@infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=y7piXdmBDL/x4wKUpL4yfLcfRL1V1CU2X+sNEky1E+A=; b=ztpYbwNu1Ix6JsNAwF1thhxZp 51JnJFP3opu9FapixnXOBLQISn3bIavs5VwpOYDraUSlDoeXdYRQ3ZKcOv6eh8IxSs/IQic82Tctj HqNh+CjbbpBr5h04zyqMq6Scc/stYKykNm/yKcqrOrbSgTtgat5tE4ylmM4f+oYSHndAa4iDAmUCh zNsP6y7VbP9c7NUBTt/yCMw0riLgsVHrGYhp0QMObC3JycTTOP35x3Gta+8QKau8fG+umGiptNgXQ XiXgqhQUPUJdkTf+sPcQZHasypJfYyXQ4UhnLrwqwAwGfleIQNJweY+FyQIgqKnQwhk3lzwkbice4 tqolYkaDg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hclbw-0005DX-5c; Mon, 17 Jun 2019 06:59:24 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 686772025A802; Mon, 17 Jun 2019 08:59:21 +0200 (CEST) Date: Mon, 17 Jun 2019 08:59:21 +0200 From: Peter Zijlstra To: Alastair D'Silva Cc: alastair@d-silva.org, 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 , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 5/5] mm/hotplug: export try_online_node Message-ID: <20190617065921.GV3436@hirez.programming.kicks-ass.net> References: <20190617043635.13201-1-alastair@au1.ibm.com> <20190617043635.13201-6-alastair@au1.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190617043635.13201-6-alastair@au1.ibm.com> User-Agent: Mutt/1.10.1 (2018-07-13) 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: 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?