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McKenney" , Neeraj Upadhyay , Randy Dunlap , Damien Le Moal , Florian Fainelli , David Hildenbrand , Zi Yan , Oscar Salvador , Hari Bathini , Kees Cook , KOSAKI Motohiro , Mel Gorman , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux.dev References: <20220913195508.3511038-1-opendmb@gmail.com> <20220913195508.3511038-4-opendmb@gmail.com> <33ff9543-3396-7609-3865-7eed20b853f5@gmail.com> From: Doug Berger In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1663178072; a=rsa-sha256; cv=none; b=fm70Iwa6RosIzARpmvwhzkOpok3KXwEw7ibBi4DySTto0GV7vjl71mXGrVdeqKbE8/cjRV /CCzk7tzQaVOhbL0SbmJI8DEw6QlPGUzUEhsi1HBR6IDm3XO6SGXtUaj750cpdZ8QSI0wG ofJT/jJUv311jiVPoT614k+vE4UysL0= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=KJeN8BAb; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf19.hostedemail.com: domain of opendmb@gmail.com designates 209.85.160.169 as permitted sender) smtp.mailfrom=opendmb@gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1663178072; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=078ohqEl3SbvSuLUyK3z9/YOVVWoH6vsNvPCy6kXlrI=; b=5OHUW3Rmg3CwaXij+tgZEvpFFl/MLTolx0urzkgu7QdeY4pNP5Fb4kPsc4oJrQF/s3LDtx OjzP4sDheVmIRpSjCwYnbWuJaErygWGE7U12yLh7lN3cj9FBZbgMaSsaIqWeQPkH6h9tJn phNqU6MKCqWrvwkQyXNW8+2KSy9xlnw= Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=KJeN8BAb; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf19.hostedemail.com: domain of opendmb@gmail.com designates 209.85.160.169 as permitted sender) smtp.mailfrom=opendmb@gmail.com X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: AD0731A0088 X-Stat-Signature: 8h8p9usg5prc43o4htcodi8nhsmbf4km X-Rspam-User: X-HE-Tag: 1663178072-805284 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 9/14/2022 10:08 AM, Mike Kravetz wrote: > On 09/13/22 18:07, Doug Berger wrote: >> On 9/13/2022 4:34 PM, Matthew Wilcox wrote: >>> On Tue, Sep 13, 2022 at 12:54:50PM -0700, Doug Berger wrote: >>>> With gigantic pages it may not be true that struct page structures >>>> are contiguous across the entire gigantic page. The mem_map_offset >>>> function is used here in place of direct pointer arithmetic to >>>> correct for this. >>> >>> We're just eliminating mem_map_offset(). Please use nth_page() >>> instead.That's good to know. I will include that in v2. > > Thanks Doug and Matthew. I will take a closer look at this series soon. > > It seems like this patch is a fix independent of the series. If so, I > would suggest sending separate to make it easy for backports to stable. Yes, as I noted in [PATCH 00/21] the first three patches fit that description, but I included them here in case someone was brave enough to attempt to use this patch set. They were in my branch for my own testing. Full disclosure: An earlier version of this patch set had more complete support for hugepage isolation that included migrating the isolation state when demoting a hugepage that touched lines in demote_free_huge_page() and depended on the subpage variable introduced here. At this point I will submit a patch for this on its own and will likely remove the first three commits when submitting V2 of the set. Thanks for your consideration. -Doug