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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 751A3CD6E55 for ; Mon, 1 Jun 2026 13:49:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=J8MuTbax1OpDSMhFOx3LhMmqnI78KaFW068v5tAv4+o=; b=E3x1+pHRimk6QinpnOoYqiYUqQ ll0Haf9D3CpzEN50PJrm7QTx2s2Nv9fVBvyCv9BPiJfRyeeBBt7U9zTIEZD88uNTM3HfArJMexQfU gaWfjfT3S6JCPYnRGPpj/PdSWY6NHM0P7+ZvzTx7mfzBVs0KX6Od2Nwp4LCgRU+D165Qea5iUCfBy F4gpFnICYcWMg4UY2F7nlxvsbXc5bM4spX3UFGsrSm10DyU/fXcs4AJ5pMj2OIYxDRJr7ZKpVSYyd 0HJ3SVRxTrm+zecnBYWA1IfPj7MK7E73bSWBjDbebpcRsqS754p3Xn63GzusxZzizTLJVSCHsifFf t2sxdrZw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wU30v-0000000BEOh-1usv; Mon, 01 Jun 2026 13:49:09 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wU30t-0000000BEOS-3ElG for linux-arm-kernel@lists.infradead.org; Mon, 01 Jun 2026 13:49:07 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 3AD8D6014C; Mon, 1 Jun 2026 13:49:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4A96A1F00893; Mon, 1 Jun 2026 13:49:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780321746; bh=J8MuTbax1OpDSMhFOx3LhMmqnI78KaFW068v5tAv4+o=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=o0sfzR162SZSavIyVSshFEI2HSXfICi4mMh2AHcrpeNw/Apq93kpeNNncZwQhxUl3 5JtWWblZ9adw1HL9epdagwm+PrTY+dMU3zxEB6zLIv+YZKfhWF6J2ehaoBd0aJl8xo 2ygjGPjWmggQ6AujluI5hNW9kN/T1ovneN/sMhwqE4jNtTRd7f+IOIct/fUSDu8MES fjNNc8chRjPuIao7ywI6mlawKV9rUUh/FdoxenP4t8V9ldxht/o8MfgcxF0sIponRB xMowtEWLSp6B4J8kHHpb9L6h7/b/dH+ET/FCeX04Mua62D3ZyZXf6xuhUwyvI7ufli hX7v2DjHvKmAw== Message-ID: <929875a2-9e94-4dbc-9c98-b342ccc3f4e2@kernel.org> Date: Mon, 1 Jun 2026 15:49:00 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 1/3] mm: make persistent huge zero folio read-only To: Dave Hansen , Xueyuan chen , akpm@linux-foundation.org, linux-mm@kvack.org 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, ryan.roberts@arm.com, dev.jain@arm.com, lance.yang@linux.dev, yang@os.amperecomputing.com, jannh@google.com References: <20260527035607.14919-1-xueyuan.chen21@gmail.com> <20260527035607.14919-2-xueyuan.chen21@gmail.com> <4e0696ee-895c-486d-aacc-71146f0e9047@intel.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. -- Cheers, David