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b=NYCjmB8ZphGxAmlYSGsmpjEjq6irXQGh39QWaFPq+buycS5sVIog4/k+nuZVTAmIj sqJltnYeiz189lDSwzBqzLuJCAwPUAomyRNAO+5zVt28zKVGMsi62bDts5zgn5pu9l chZ4Z9sKT6wgfHlb1v0m2HkyBvH+OgKXLL+7a4xIok3r7Q3flC9THfiSILZCLJ6LXf RvEfP/oi9ShH0Ddw6XmUn2RW+6Ik+6aFTXI/HghAJ4EZzIUazBelXziA5rsfWRUShm +X6tRmnkJ55Zb6Nkt+fhJYKzPAhIpwzSOZOCcCEtA/6vO9FVQZGWTcNqi0Zug8tQWw OB1486nsghd/g== Message-ID: Date: Fri, 8 May 2026 21:29:38 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/2] mm/khugepaged: fix spurious -EINVAL from sub-PMD MADV_COLLAPSE range To: Lorenzo Stoakes , Chen Wandun Cc: akpm@linux-foundation.org, shuah@kernel.org, zokeefe@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org References: <20260507070558.3064142-1-chenwandun@lixiang.com> <20260507070558.3064142-2-chenwandun@lixiang.com> <9eea2afb-8c35-47eb-b1de-6a08503c9679@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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: F0FAD180008 X-Rspamd-Server: rspam04 X-Stat-Signature: fb3ryre5n3hjf7szm59gyi7qe5m1mes1 X-HE-Tag: 1778268584-768956 X-HE-Meta: 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 C2CAGLxS uPWR2ZCGFGDLc7diMWWgNUIMAecewjw/mSNzbzdlNsr0cKKH05Y/9wQe0GdC/ge2pqire+c+SdaqfzUA+UjNwctV2IXXyJqRxPe8OanqFvJVtid6/sdl4klhNvCjwc/+lQuCQV1hX7ugtBjZWO37ylieVyITzpPnxpvrj/6y89CvSWztH3p6nzxegsipnmnqb6kqmKL3h9Xs3hXg3fsuo3/r1wosz97lSIX7v04sByLPsPIbDVjConrwGpkUKgqRNt+MJJHYKx3E2AFOn1IdzF6neL6vxMr/Rdokv Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: >> >> In general, LGTM, but see for conflict: >> https://lore.kernel.org/all/20260409014323.2385982-1-ye.liu@linux.dev/ > > Please use mm-unstable as a basis for your mm work Chen, this is something you > need to fix, the patch above has been around for a while and is in > mm-unstable. > > You have patches in mm already so you should know better by now. > > But I'm really not sure I'm in favour of this anyway. I'll defer to David but > this feels useless to me. I don't enjoy the underflow in the return statement, so I think we should just clean that up. -- Cheers, David