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Shutemov" , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <1597423766-27849-1-git-send-email-opendmb@gmail.com> <20200818201817.351499e75cba2a84e8bf33e6@linux-foundation.org> <20200819102214.32238093b116ab6f1c5c7b73@linux-foundation.org> <50ad53dc-faf2-3014-bac3-be370b972f59@gmail.com> <20200819104057.4b91898b76302b7b1c3e8e56@linux-foundation.org> From: Doug Berger Message-ID: <65909c25-71b2-0116-1ac7-a56118bca86e@gmail.com> Date: Wed, 19 Aug 2020 17:32:35 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20200819104057.4b91898b76302b7b1c3e8e56@linux-foundation.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 2D141180442C0 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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 8/19/2020 10:40 AM, Andrew Morton wrote: > On Wed, 19 Aug 2020 10:30:25 -0700 Florian Fainelli wrote: > >> On 8/19/20 10:22 AM, Andrew Morton wrote: >>> On Wed, 19 Aug 2020 10:15:53 -0700 Florian Fainelli wrote: >>> >>>>>> In many cases the difference is not significant, but for example >>>>>> an ARM platform with 1GB of memory and the following memory layout >>>>>> [ 0.000000] cma: Reserved 256 MiB at 0x0000000030000000 >>>>>> [ 0.000000] Zone ranges: >>>>>> [ 0.000000] DMA [mem 0x0000000000000000-0x000000002fffffff] >>>>>> [ 0.000000] Normal empty >>>>>> [ 0.000000] HighMem [mem 0x0000000030000000-0x000000003fffffff] >>>>>> >>>>>> would result in 0 lowmem_reserve for the DMA zone. This would allow >>>>>> userspace to deplete the DMA zone easily. >>>>> >>>>> Sounds fairly serious for thos machines. Was a cc:stable considered? >>>> >>>> Since there is a Fixes: tag, it may have been assumed that the patch >>>> would be picked up and as soon as it reaches Linus' tree it would be >>>> picked up by the stable selection. >>> >>> It doesn't work that way - sometimes a fix isn't considered important >>> enough to backport. It could just fix a typo in a comment! >> >> Then can this be applied ASAP and back ported? > > Sure. > As Florian guessed, I assumed the Fixes: tag was a sufficient clue since I wouldn't normally apply a Fixes tag to a typo correction in a comment. I suspect I have been spoiled by David Miller :). Thanks for the quick turn-around and applying the cc:stable to the mmotm, Doug