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Howlett" , Lorenzo Stoakes , Vlastimil Babka , Jann Horn References: <20250303163014.1128035-1-david@redhat.com> <20250303163014.1128035-21-david@redhat.com> <20251014122335.dpyk5advbkioojnm@master> <71380b43-c23c-42b5-8aab-f158bb37bc75@redhat.com> <20251015004543.md5x4cjtkyjzpf4b@master> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZoEEwEIAEQCGwMCF4ACGQEFCwkIBwICIgIG FQoJCAsCBBYCAwECHgcWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaJzangUJJlgIpAAKCRBN 3hD3AP+DWhAxD/9wcL0A+2rtaAmutaKTfxhTP0b4AAp1r/eLxjrbfbCCmh4pqzBhmSX/4z11 opn2KqcOsueRF1t2ENLOWzQu3Roiny2HOU7DajqB4dm1BVMaXQya5ae2ghzlJN9SIoopTWlR 0Af3hPj5E2PYvQhlcqeoehKlBo9rROJv/rjmr2x0yOM8qeTroH/ZzNlCtJ56AsE6Tvl+r7cW 3x7/Jq5WvWeudKrhFh7/yQ7eRvHCjd9bBrZTlgAfiHmX9AnCCPRPpNGNedV9Yty2Jnxhfmbv Pw37LA/jef8zlCDyUh2KCU1xVEOWqg15o1RtTyGV1nXV2O/mfuQJud5vIgzBvHhypc3p6VZJ lEf8YmT+Ol5P7SfCs5/uGdWUYQEMqOlg6w9R4Pe8d+mk8KGvfE9/zTwGg0nRgKqlQXrWRERv cuEwQbridlPAoQHrFWtwpgYMXx2TaZ3sihcIPo9uU5eBs0rf4mOERY75SK+Ekayv2ucTfjxr Kf014py2aoRJHuvy85ee/zIyLmve5hngZTTe3Wg3TInT9UTFzTPhItam6dZ1xqdTGHZYGU0O otRHcwLGt470grdiob6PfVTXoHlBvkWRadMhSuG4RORCDpq89vu5QralFNIf3EysNohoFy2A LYg2/D53xbU/aa4DDzBb5b1Rkg/udO1gZocVQWrDh6I2K3+cCs7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20251015004543.md5x4cjtkyjzpf4b@master> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: yWYcmZXhw3gmETfzS-SUELo8d4GldYzs_2DYGasP_GU_1760968388 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam05 X-Stat-Signature: o1i6f4b37njrf7ri9dawbotuuahdz1rt X-Rspam-User: X-Rspamd-Queue-Id: 87C8F20005 X-HE-Tag: 1760968391-979634 X-HE-Meta: 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 +PPJgqIz 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 15.10.25 02:45, Wei Yang wrote: > On Tue, Oct 14, 2025 at 04:38:38PM +0200, David Hildenbrand wrote: >> On 14.10.25 16:32, Matthew Wilcox wrote: >>> On Tue, Oct 14, 2025 at 02:59:30PM +0200, David Hildenbrand wrote: >>>>> As commit 349994cf61e6 mentioned, we don't support partially mapped PUD-sized >>>>> folio yet. >>>> >>>> We do support partially mapped PUD-sized folios I think, but not anonymous >>>> PUD-sized folios. >>> >>> I don't think so? The only mechanism I know of to allocate PUD-sized >>> chunks of memory is hugetlb, and that doesn't permit partial mappings. >> >> Greetings from the latest DAX rework :) > > After a re-think, do you think it's better to align the behavior between > CONFIG_NO_PAGE_MAPCOUNT and CONFIG_PAGE_MAPCOUNT? > > It looks we treat a PUD-sized folio partially_mapped if CONFIG_NO_PAGE_MAPCOUNT, > but !partially_mapped if CONFIG_PAGE_MAPCOUNT, if my understanding is correct. I'd just leave it alone unless there is a problem right now. -- Cheers David / dhildenb