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Wysocki" , Andrew Morton , Pavel Tatashin , Oscar Salvador , Mike Rapoport , Baoquan He , Wei Yang , Logan Gunthorpe , linux-kernel@vger.kernel.org, linux-mm@kvack.org Date: Wed, 26 Jun 2019 16:27:30 +1000 In-Reply-To: <20190626062113.GF17798@dhcp22.suse.cz> References: <20190626061124.16013-1-alastair@au1.ibm.com> <20190626061124.16013-2-alastair@au1.ibm.com> <20190626062113.GF17798@dhcp22.suse.cz> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.32.2 (3.32.2-1.fc30) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.6.2 (mail2.nmnhosting.com [10.0.1.20]); Wed, 26 Jun 2019 16:27:47 +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: On Wed, 2019-06-26 at 08:21 +0200, Michal Hocko wrote: > On Wed 26-06-19 16:11:21, Alastair D'Silva wrote: > > From: Alastair D'Silva > > > > If a memory section comes in where the physical address is greater > > than > > that which is managed by the kernel, this function would not > > trigger the > > bug and instead return a bogus section number. > > > > This patch tracks whether the section was actually found, and > > triggers the > > bug if not. > > Why do we want/need that? In other words the changelog should contina > WHY and WHAT. This one contains only the later one. > Thanks, I'll update the comment. During driver development, I tried adding peristent memory at a memory address that exceeded the maximum permissable address for the platform. This caused __section_nr to silently return bogus section numbers, rather than complaining. -- Alastair D'Silva mob: 0423 762 819 skype: alastair_dsilva Twitter: @EvilDeece blog: http://alastair.d-silva.org