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[2003:d8:2f3f:f800:c101:5c9f:3bc9:3d08]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-40fc5602dc2sm2225863f8f.32.2025.09.25.02.38.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 25 Sep 2025 02:38:41 -0700 (PDT) Message-ID: <54195a6a-7cc6-4df1-a787-45d8f564c0bd@redhat.com> Date: Thu, 25 Sep 2025 11:38:38 +0200 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 RFC 2/2] mm: add PMD-level huge page support for remap_pfn_range() To: Yin Tirui , akpm@linux-foundation.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, ziy@nvidia.com, baolin.wang@linux.alibaba.com, npache@redhat.com, ryan.roberts@arm.com, dev.jain@arm.com, baohua@kernel.org, catalin.marinas@arm.com, will@kernel.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, anshuman.khandual@arm.com, yangyicong@hisilicon.com, ardb@kernel.org, willy@infradead.org, apopple@nvidia.com, samuel.holland@sifive.com, luxu.kernel@bytedance.com, abrestic@rivosinc.com, yongxuan.wang@sifive.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org Cc: wangkefeng.wang@huawei.com, chenjun102@huawei.com References: <20250923133104.926672-1-yintirui@huawei.com> <20250923133104.926672-3-yintirui@huawei.com> <8313b0c1-bf62-4257-951c-fd7e29193ae2@huawei.com> From: David Hildenbrand Content-Language: en-US Autocrypt: addr=david@redhat.com; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 25.09.25 03:43, Yin Tirui wrote: > > > On 9/24/2025 5:50 PM, David Hildenbrand wrote: >>> Introduce pfnmap_max_page_shift parameter to control maximum page >>> size and "nohugepfnmap" boot option to disable huge pfnmap entirely. >> >> Why? If an arch supports it we should just do it. Or what's the reason >> behind that? >> > There's no specific reason for this - it was just intended to provide an > additional option. I'll remove it in the next version. Good, then let's keep it simple :) -- Cheers David / dhildenb