From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A788AC9833F for ; Mon, 28 Sep 2026 12:09:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9DF746B00AA; Mon, 28 Sep 2026 08:09:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9903A6B00AB; Mon, 28 Sep 2026 08:09:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 831D06B00AC; Mon, 28 Sep 2026 08:09:01 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 5F0E16B00AA for ; Mon, 28 Sep 2026 08:09:01 -0400 (EDT) Received: from smtpin08.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay08.hostedemail.com (Postfix) with ESMTP id D8A911401CC for ; Mon, 28 Sep 2026 12:09:00 +0000 (UTC) X-FDA: 85263050040.08.EC12E41 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf11.hostedemail.com (Postfix) with ESMTP id 237DA40006 for ; Mon, 28 Sep 2026 12:08:59 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="DK/DhmZE"; spf=pass (imf11.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790597339; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=flBS/IV2cTEEpYFIE9hkK0/gJv363zv18xBTvbduC1Q=; b=i9cRTILIh/pWosTBGXaaLZtNpajFmPM6iPkkSyDtqefuPtscu7UAX/uWaoUxE/SkTJGWRY 0az16tGn/W75nv+cbjHHWNAElDW0pY1yQzG9cqn7Mxy1oXH22O55YdehnIvNHBM4gkRdRq iPD2AdhjM1fi/5V7uE2jp2G3SiVK1tQ= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790597339; b=1is5msF6aK1S2kBOwmvpKdYkSLWRcWfKRPTKAxbmzGtTNszVv6mIJzmddEKMMUDKDjShaJ 1f9A7nQWFQTt2KFoMd2hKrndfLIYCHlWrp0Ww0VckkIXYulD5T+RS1T0XQtBWjiECDLV0F WRyAFq7Tn0Qh8YL0owZ/fv/CdH36mZc= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="DK/DhmZE"; spf=pass (imf11.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id A3FF960052; Mon, 28 Sep 2026 12:08:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD7CE1F000FF; Mon, 28 Sep 2026 12:08:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790597338; bh=flBS/IV2cTEEpYFIE9hkK0/gJv363zv18xBTvbduC1Q=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=DK/DhmZE5PxjjfiTysNrAMQsD0tPfbAlK4N0oGiIoKpm38aVEaVy4jAC1Y+K6ec4O IHihgKxwhcgEQbMwynntS1fJakS8jaWRXcnkQ6ZPuWLd9u1hAHxvQ/ohwFAkbdRlY/ rwgISzCsiwPvL9fX/0Dvrq9/ZLHGjgYxVIN2OzWRbioTSr3hjdaoaL3Yu6xvbcyGDS oLJhM7NBnxMup0u+/pPwdJzHPb19xd05lEGC/VIZzLlMnYyowqUgQvss4lUJre4ZW7 oHiDaBdfqwJUfUjnKUNON2bn+UlTXjhpRRR8qBxzHlZxV74PLDGNsaTSkWP6cx46iO usPjeC9PiMZrQ== Message-ID: Date: Mon, 28 Sep 2026 14:08:51 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] selftests/mm: check MREMAP_DONTUNMAP mlock accounting To: "Jose A. Perez de Azpillaga" , Andrew Morton , Shuah Khan Cc: Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260928111055.482136-1-azpijr@gmail.com> 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: <20260928111055.482136-1-azpijr@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: t5boucjsyqeto1qmogpwgzrzahm19xij X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 237DA40006 X-HE-Tag: 1790597339-312334 X-HE-Meta: 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 fHqhbceX voRbN2+UIlhfdVZpVMEc4X8suozbOuEe91vwlucAjanB/enKilxTM+FAQSOXspSEJM/A5kmXFoTUkOdL+wVXgPvp9E/2hJJhkd2/hcB+3CHZdNo8r4aIKmF6PviXi3bvwELMKdkdSN+FQWXiDfnp7fck6zCqOCWE+eCMmeNjFAMJAjdSfgPNxzHtC7jNZRq58wnV6FUzOv/GLlgyX2lXkJeci2CecuK/G0GqDbdl03USlmUeD29vOZCzCzYfljXZqBKIt05XTemh034fImNyEKlKDJlqh8gvk89c8lcwjYrE0edurcoOyejZfK89LguQrM8LHhlrh9MO22co= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/28/26 13:10, Jose A. Perez de Azpillaga wrote: > MREMAP_DONTUNMAP keeps the source VMA in place, but clears its mlock flags > for the whole VMA while setting them on the destination VMA. Two cases > leak mm->locked_vm as a result: > > - an unfaulted mlock-on-fault VMA moved behind itself self-merges, so the > single resulting VMA loses the flags without the accounting being > dropped; > > - a partial mremap() moves only part of the range, leaving the pages which > are not moved accounted as locked in a VMA whose flags were cleared. > > Add three cases to the MREMAP_DONTUNMAP selftest which mlock() the source > VMA, with and without MLOCK_ONFAULT, perform the operation and check that > VmLck comes back to zero once everything is unmapped. Each case runs in > its own process, so it starts from a clean mm with VmLck at zero and a > failure cannot propagate to the cases which follow. > > Verified on x86_64: the three cases fail on v7.3-rc5 and pass on > mm-unstable with the fixes from the "mm/mremap: fix two issues with > MREMAP_DONTUNMAP" series applied. > > Signed-off-by: Jose A. Perez de Azpillaga > --- > tools/testing/selftests/mm/mremap_dontunmap.c | 273 +++++++++++++++++- @Lorenzo, could something like this also be implemented (maybe with less churn) in the vma.c selftests? -- Cheers, David