From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 20E2A4B04BB; Fri, 7 Aug 2026 00:09:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786061383; cv=none; b=u937FTbH6gLDbZJsJH4ikZA4mS23rVAHrqS5BEn54SaJ743PFxlPAzpQGZkVfBeLuoyzlV+rKQZzyCsN9wqrlevKlMXGgITF2E6N5pz7GMRC8AJxZJdD4EoN8zqQFXb/YhvaAtqdX4IGDSmT6UF2pFfB9R5/hAEHFVqIG3wRmrY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786061383; c=relaxed/simple; bh=VmLPvq4wC1IfP0SAylF++I5+i23jCGBcmntRCvsz83U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Z8TjIM/+W7coSXuR+exX9bq3uruK65fajNw4mO7MSV841PEGUQAR+znMn8odd+K5m/ict4fgAZmcybbMG7G/mRmLuOD1yAt/ZWgSECp5+0iIF1LjkrYpVY8o5az/QbzR1lu+BEoDajDSsRNJckAB+Tf49LKQXAXO68Edrbgf3FI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BtbvyL6Z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BtbvyL6Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9CA41F000E9; Fri, 7 Aug 2026 00:09:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786061381; bh=dZ5Mw0Ih/bGAuN0BQFkuLqJf8PbwxdcGV24qNLgz+NA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BtbvyL6ZMna8HAKgywO+rmaE4EQ85ji20cRsyI/3rtd1ai4+PCGAzcDE93xIF5Q01 B5BPh1oT4iTNs4IeHq+V7rWpXGIUqY9UjANEHMscGd2ARRJs1f4bClCc2IVrjqyexY XUXyEamjhpdN2aKu6SGIKd3aPS6x7dmhedDRHgcR6tOCY0ra90pVNPjCvTQqxHeMir gEt5KBBtiAUiewgz9RD3+3mEMLIayqTrYkKPPkkL1BF38WsWPh6O16xDd7F4uYAqJN AYVP6E380raZ6o6msbOO9O48SiLrGXWXY+fzM+hCHndtqKax52BIy8rtMAca2XtbwA MfiLBnnWXt7UA== From: SJ Park To: Gregory Price Cc: SJ Park , "Lorenzo Stoakes (ARM)" , linux-mm@kvack.org, damon@lists.linux.dev, linux-kernel@vger.kernel.org, kernel-team@meta.com, akpm@linux-foundation.org, david@kernel.org, ziy@nvidia.com, baolin.wang@linux.alibaba.com, liam@infradead.org, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, usama.arif@linux.dev, vbabka@kernel.org, jannh@google.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, ying.huang@linux.alibaba.com, apopple@nvidia.com Subject: Re: [PATCH 1/4] mm/damon: defensively skip zone device folios in damon_get_folio() Date: Thu, 6 Aug 2026 17:09:37 -0700 Message-ID: <20260807000938.79851-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Thu, 6 Aug 2026 12:05:00 -0500 Gregory Price wrote: > On Thu, Aug 06, 2026 at 02:37:59PM +0100, Lorenzo Stoakes (ARM) wrote: > > On Tue, Jul 28, 2026 at 03:47:11PM -0400, Gregory Price wrote: > > > All DAMON physical- and virtual-address operations obtain their folios > > > through damon_get_folio(). That helper already excludes ZONE_DEVICE > > > memory implicitly via pfn_to_online_page() and folio_test_lru(), but > > > this is inconsistent with other callers in mm/ which test explicitly. > > > > > > Add an explicit folio_is_zone_device() rejection in damon_get_folio() > > > so the guarantee lives in one place and covers every caller uniformly, > > > consistent with other mm walkers that reject zone device folios. > > > > > > Signed-off-by: Gregory Price (Meta) > > > > Thanks, nice to make it explicit! > > > > Acked-by: Lorenzo Stoakes (ARM) > > > > SJ Asked me to drop it, I didn't asked you to drop this. I asked your thought about revisioning this for my concern. And you replied [1] you can drop this. I interprete it as a withdrawal, rather than being asked to be dropped. My dictionary is definitely not a good one, though. Anyway, if your intention was not withdrawing, please feel free to push back with the original change (explain me why my concern is wrong) or restart a discussion for making DAMON code better in a way that can resolve both of our concerns. [1] https://lore.kernel.org/amoXZr2vB_q5q5Wu@gourry-fedora-PF4VCD3F Thanks, SJ [...]