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X-CSE-ConnectionGUID: 6pkb2x7ySLiLRaaJl0VOCw== X-CSE-MsgGUID: HebQIQndQy+jgpY16XSGrw== X-IronPort-AV: E=McAfee;i="6800,10657,11894"; a="88618497" X-IronPort-AV: E=Sophos;i="6.25,258,1779174000"; d="scan'208";a="88618497" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Sep 2026 13:59:19 -0700 X-CSE-ConnectionGUID: ikwRYlfkQFWAwOzWRoIzTQ== X-CSE-MsgGUID: eJoC9yYvSRuQE0aGcQiTIw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,258,1779174000"; d="scan'208";a="265198010" Received: from cjhill-mobl.amr.corp.intel.com (HELO [10.125.110.134]) ([10.125.110.134]) by fmviesa006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Sep 2026 13:59:17 -0700 Message-ID: <5026dbec-0b71-4408-a78a-484a4b8e77dd@intel.com> Date: Wed, 2 Sep 2026 13:59:15 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 1/3] mm: make persistent huge zero folio read-only To: Xueyuan Chen , akpm@linux-foundation.org Cc: david@kernel.org, ljs@kernel.org, usama.arif@linux.dev, ziy@nvidia.com, baolin.wang@linux.alibaba.com, liam@infradead.org, nico.pache@linux.dev, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, lance.yang@linux.dev, kas@kernel.org, rppt@kernel.org, catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, tglx@kernel.org, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, peterz@infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260901151818.3191443-1-xueyuan.chen21@gmail.com> <20260901151818.3191443-2-xueyuan.chen21@gmail.com> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/1/26 08:18, Xueyuan Chen wrote: > +static inline int set_direct_map_ro(struct page *page, unsigned int nr) > +{ > + return 0; > +} I still really think the stub here needs to return an error *or* the thing needs to just be void and tell folks that they can't know whether it worked or not.