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Tsirkin" Cc: Gregory Price , linux-kernel@vger.kernel.org, Andrew Morton , Vlastimil Babka , Brendan Jackman , Michal Hocko , Suren Baghdasaryan , Jason Wang , Andrea Arcangeli , linux-mm@kvack.org, virtualization@lists.linux.dev, Johannes Weiner , Zi Yan , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , "Matthew Wilcox (Oracle)" , Muchun Song , Oscar Salvador , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Ying Huang , Alistair Popple , Hugh Dickins , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , linux-fsdevel@vger.kernel.org References: <9dd9deabd42801f3c344326991d1431c3d8db39d.1776808210.git.mst@redhat.com> <20260422171315-mutt-send-email-mst@kernel.org> <20260423074433-mutt-send-email-mst@kernel.org> <88b0765f-7cfc-4e44-83d2-c01a1755c842@kernel.org> <20260423104120-mutt-send-email-mst@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+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: <20260423104120-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam10 X-Stat-Signature: kwsyof1b9d85k8fknk38udaysfjheotk X-Rspam-User: X-Rspamd-Queue-Id: 1DE914000C X-HE-Tag: 1776959681-816180 X-HE-Meta: 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 I4bvVlWa GaVvkpfAyWaFTVMR5Dnm0++SclDnxzz1OYqPd5hAzdal4mXjxG1s0avDsHmbVdhE+QZXgU4Bg+YYx752n04vx55Tq9fESFLxwwXdAAAGbrjbSlj01c1BnQzlU0vq3Oh8aYHEIsRT3DpfTmlRU6KLqK/LEFfOXN2KZWmFg92fhz7ZH5zU1B/vP3S2COhus6eZuJPXNq0LRKzN5p6LpCio5j0O5Tne4i9E+PI6rIvAtRvAHUFf7iow+4JIfnDU1uhAr6G2+flQ/qQIttL1jMR/U+7+Hvrh70wJYO6KS/db+NbQNR9wnZhGJMoRgi8bITUaZEjWDBkn4t+PJY7znQTmZ62JKWpQlJRh9ygSLTVosd2hfDXB6IBcye5u+xsM5ccFWu7bp Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/23/26 16:46, Michael S. Tsirkin wrote: > On Thu, Apr 23, 2026 at 04:13:50PM +0200, David Hildenbrand (Arm) wrote: >> But really, that hugetlb code is rather messy. I'd vote for leaving hugetlb >> alone on a v1, and focusing on non-hugetlb first. > > I just dislike it when things are non orthogonal. > People are used to: hugetlb = same perf as THP but more predictable at the cost > of being harder to use and using more resources. > Here, suddenly, we have an optimization but only for THP. Note that we also didn't care about user_alloc_needs_zeroing() with hugetlb so far. It's not that it cannot be done with hugetlb, it's just a question about how it can be done more cleanly; and that requires more work to clean the hugetlb part up. Best done separately. -- Cheers, David