From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 719ADCD6E55 for ; Mon, 1 Jun 2026 15:44:21 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C2B2F6B042F; Mon, 1 Jun 2026 11:44:20 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C04046B0431; Mon, 1 Jun 2026 11:44:20 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B405D6B0432; Mon, 1 Jun 2026 11:44:20 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id A77286B042F for ; Mon, 1 Jun 2026 11:44:20 -0400 (EDT) Received: from smtpin18.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 5977A1C0C66 for ; Mon, 1 Jun 2026 15:44:20 +0000 (UTC) X-FDA: 84831765480.18.A664E45 Received: from out-178.mta0.migadu.com (out-178.mta0.migadu.com [91.218.175.178]) by imf09.hostedemail.com (Postfix) with ESMTP id 5BE6B140011 for ; Mon, 1 Jun 2026 15:44:18 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=SW2HVAvw; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf09.hostedemail.com: domain of lance.yang@linux.dev designates 91.218.175.178 as permitted sender) smtp.mailfrom=lance.yang@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1780328658; 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=mgxgY8d+G/6RTOQ+BJPpqzlDf4UdD5DQTydgCd5fyJg=; b=VFM6+FwLKVRw3lWhkx57r/ZgGk9pnWDj4U/89VZkPjEcFHAna3vRoMdGkhCISm8ITkVX4W mahs4OtDrdCr/Bh//QgvgI35dZR4yf/oXQn/wXmLGx9DVFrFW8Gs7i5VxRL06VIJdzTGs1 HTiN0rNgJ6lqeJn5lb7bx1FQb8rllWU= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=SW2HVAvw; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf09.hostedemail.com: domain of lance.yang@linux.dev designates 91.218.175.178 as permitted sender) smtp.mailfrom=lance.yang@linux.dev ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1780328658; b=qz8u5G3FiVlO4hkTWW0/pu83h/JGETk9H9MpyLX3wg5lr8YBA3NQhM0eAKiC/gjIbjDss7 0bpYVSajFn5OtipgqWC6aT8/Vz3VVyy882MZb1z89PNBGWRpNYhU+8xHpM7OBZJWlLvk75 5PqlEyq51nK2pUToHklf4EvrOBHMlx4= Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1780328656; h=from:from: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; bh=mgxgY8d+G/6RTOQ+BJPpqzlDf4UdD5DQTydgCd5fyJg=; b=SW2HVAvw2yZu4I9MOOCod0UfssJYy4pt1A9hpEgVLqAe2/h1H9PZfGvrqmQ/pQbWApbAVx B2oofFQxFPT+jwLRowiWeqH/MqwmXVsj9A2gLQChaPYxKS5mCUEsoS/sy7zrgP4Ss71B8M J/USgdBKjwLAy16nGeLo9BqWWNTSL38= Date: Mon, 1 Jun 2026 23:43:56 +0800 MIME-Version: 1.0 Subject: Re: [RFC PATCH 1/3] mm: make persistent huge zero folio read-only Content-Language: en-US To: "David Hildenbrand (Arm)" , Dave Hansen , Xueyuan chen Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, catalin.marinas@arm.com, will@kernel.org, tglx@kernel.org, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, ljs@kernel.org, ziy@nvidia.com, baolin.wang@linux.alibaba.com, akpm@linux-foundation.org, ryan.roberts@arm.com, dev.jain@arm.com, yang@os.amperecomputing.com, jannh@google.com, linux-mm@kvack.org References: <20260527035607.14919-1-xueyuan.chen21@gmail.com> <20260527035607.14919-2-xueyuan.chen21@gmail.com> <4e0696ee-895c-486d-aacc-71146f0e9047@intel.com> <929875a2-9e94-4dbc-9c98-b342ccc3f4e2@kernel.org> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Lance Yang In-Reply-To: <929875a2-9e94-4dbc-9c98-b342ccc3f4e2@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 5BE6B140011 X-Rspam-User: X-Stat-Signature: wtbucrwstnhnd6661e4mqgr87rwmmabd X-Rspamd-Server: rspam09 X-HE-Tag: 1780328658-265008 X-HE-Meta: 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 kRZ4wWEk wNGBGtOvm9fC6pyn5ZmpdDJCdqAX2oKnbZ2PWmj9KQ06ThLAteLSodpnU7JuOc4urQbz63aSJmum3XY8UcIGzYRO5NqEjK0yKnqDumuHr0vq4XyFPwNgeQaARx64vfbUH5hZMMLMZgaXuZxNn/n4A1D6UGnEyLJx6/6VRW31WZ0igSaELc8VELr7X4cBxSQ0fTE4vZR4wRg+vaGKLfB75D1y/x/FP+aDPm8DLiTKGZjjs90XeC9CeSgxUrPfEQVYEU3EE+Ut/TRwFsu4+cvWlDYU9BH217HPcfIWV Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026/6/1 21:49, David Hildenbrand (Arm) wrote: > On 5/27/26 17:55, Dave Hansen wrote: >> On 5/26/26 20:56, Xueyuan chen wrote:> +#ifdef >> CONFIG_READONLY_HUGE_ZERO_FOLIO >>> +bool __init arch_make_huge_zero_folio_readonly(struct folio *folio); >>> +#endif >> >> All of the #ifdeffery needs to die, IMNHO. >> >> This function is also a bad idea. There is nothing "huge zero" specific >> about it. It takes any old folio and tries to make it read only. >> >> Just make it: >> >> bool __init arch_make_folio_readonly(struct folio *folio) >> > > I'm not sure whether we want a folio-based interface, though. > > This will likely be the only folio (that will actually have a "struct folio" in > the future) compound page we'll ever mark read-only ... whereby I'd guess we'd > want other non-folio pages to be read-only in the future (encryption keys etc, > maybe?). > > So I'd instead use a page-range based interface or sth like that. Just to check, did you mean something like: bool arch_make_pages_readonly(struct page *page, int nr_pages); ? So it can work on pages as well, not only folios :)