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 B316EC43458 for ; Fri, 26 Jun 2026 15:58:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 903AC6B00E7; Fri, 26 Jun 2026 11:58:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8B48D6B00E8; Fri, 26 Jun 2026 11:58:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 77E056B00E9; Fri, 26 Jun 2026 11:58:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 43E3A6B00E7 for ; Fri, 26 Jun 2026 11:58:33 -0400 (EDT) Received: from smtpin12.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id AE0E6C21CD for ; Fri, 26 Jun 2026 15:58:32 +0000 (UTC) X-FDA: 84922521264.12.F807574 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf12.hostedemail.com (Postfix) with ESMTP id E781140006 for ; Fri, 26 Jun 2026 15:58:30 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="eiJy/zda"; spf=pass (imf12.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-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1782489510; b=ZqzZfaAOh+1Ercp9Y8Owx+P+nfg7AcunixYk9c2uv7CKcSai/fSVMcalGm7/ovl8SE8ROQ 587VUMZLglDWQ0L7oD1A1t3pq7gNt7UWT4GBzeSF1MFtak+i4E8BqtBmHKaiiD1k9wPkOo vBNK/4O4sXczHMhI0vGzDjIm/Up7BCk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1782489510; 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=H6d+YLPQTkEvAUlX9G2988IQYpQyGM7qnUDQ1M55AmA=; b=RgbNRGxVt+uD9MYROIlRMOsCQ4bNLIO3usm/YRLrx3lFPanfYYU1SWHaISamPp2kVS2cN7 4cZpDWZv1E2MrwDi1Oxf1yJthdTrZkQHjWyLUfJexvjGgBcSqqbDWkz9KAI8CuWD1GB3OX eIywMwbvwQg29xE2go9FYMpDgiSO6Ng= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="eiJy/zda"; spf=pass (imf12.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 424EC600DA; Fri, 26 Jun 2026 15:58:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B607B1F000E9; Fri, 26 Jun 2026 15:58:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782489510; bh=H6d+YLPQTkEvAUlX9G2988IQYpQyGM7qnUDQ1M55AmA=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=eiJy/zda2dkjWvhl72LqpuslGv70vZCKzdM+1+82fNF3ihLtBA9e5sChiFSthzH6r RMwCIcjusgL3BEtZ67F+LqwaPbgPelTrDjV6bLrgn1wRiIRDtTPU2o80x3YaNQ6KQm UI8m6pDX3AH0G8z6yG+wGMDgorpz2nhU+Qt7h/MEhTtfB33/Ynx+msP9wPYgiGhCNX LRnIxj6OzDpDq1jE8aVgDcRzbMVburr+lv91ybgLHFTBOfJT9FVs66m9UrxlpSjmy8 m5SZZhdJ95aCy0+IAD1fb60OM2XQPEhgK86nLBt0Ot9K27d81gqrHAFGwIEESsUmTW B/F9mEO/OwQAw== Message-ID: Date: Fri, 26 Jun 2026 17:58:25 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/4] mm: mincore: use walk_page_range_vma() in do_mincore() To: Kefeng Wang , Andrew Morton , Alistair Popple , Gregory Price Cc: Pedro Falcato , Zi Yan , "Liam R. Howlett" , Lorenzo Stoakes , Vlastimil Babka , Suren Baghdasaryan , linux-mm@kvack.org References: <20260618092845.3905740-1-wangkefeng.wang@huawei.com> <20260618092845.3905740-2-wangkefeng.wang@huawei.com> <42e167b2-5676-45fd-8f3a-738d2f4f6623@huawei.com> <20260624193852.2a1ac8a187978e4baa75f47e@linux-foundation.org> <1b34ac03-edf7-4219-a334-1e7b7292129b@huawei.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: <1b34ac03-edf7-4219-a334-1e7b7292129b@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Stat-Signature: mkk4ikwcz7ajj74drxoxm143euetr6k6 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: E781140006 X-HE-Tag: 1782489510-864598 X-HE-Meta: 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 aNMfa7tP cyxrYQjAFPLePahYZ952bZ87tzmkThcUQ/UWt98UvvjKAMyR+pWO1U75XGJtyBklCWvDdka7ohBxuSONwHhXOYl14qMoXX+8DbW+W6lbr07RUddFlgoo6shsNN+pSqqWM46+Kn6zZivFxrXFJw/y3doBP1+nbuYKT1m36giZzBLqrQZMLzubUEXm9b7TlKeIy0aPVSYIPmK4FpXc8Zhn3v5Juv6CI922K88FR+37IqwX+UV6HrBzKQjlc3AEgRTB3CHSiRx6tkd9tHgMWY7joJ4mSePvT+/FOBYAZR74gzkBhnyH2ROnzePNW715UaeoOaNN0yiZwQAFuw4KfssdYBpHmAZUaQGVabU9fqLNGBbmV0jaJpuPz1gYM/7DM2eBSsLOmq4d1KL9aJa6fHyr1Z53+UA9vajI/+t52 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/26/26 17:21, Kefeng Wang wrote: > > > On 6/25/2026 10:38 AM, Andrew Morton wrote: >> On Mon, 22 Jun 2026 11:23:11 +0800 Kefeng Wang >> wrote: >> >>> >>> Hope Andrew can fix the comments when pickup patches. >> >> I added this: >> >> --- a/mm/mincore.c~mm-mincore-use-walk_page_range_vma-in-do_mincore-fix >> +++ a/mm/mincore.c >> @@ -261,12 +261,7 @@ static long do_mincore(unsigned long add >>       } >>         /* >> -     * walk_page_range_vma() does not call walk_page_test(), which >> -     * handles VM_PFNMAP VMA by invoking ->pte_hole() to skip the >> -     * page table walk. Without this check, PFNMAP PTEs would be >> -     * treated as present by mincore_pte_range(), changing the returned >> -     * residency status from the historical "not resident" to "resident". >> -     * Handle VM_PFNMAP explicitly to preserve the original behavior. >> +     * mincore historically reports PFNMAP mappings as non-resident. >>        */ >>       if (vma->vm_flags & VM_PFNMAP) { >>           __mincore_unmapped_range(addr, end, vma, vec); >> _ >> > > Thanks. > >> >> Sashiko is OK with your patchset, but it might have found four(!) >> pre-existing issues: >> >>     https://sashiko.dev/#/patchset/20260618092845.3905740-1- >> wangkefeng.wang@huawei.com >> > > Sorry for the late, this is pre-existing issue, I am not familiar with > zone devices, so just focus on my changes and the subsequent > changes related to mincore.. After a quick review, most of them are not > issues based on my understanding. > > + CC Alistair and Gregroy for migrate_device.c, also Zi could you help > to check it? > > 1. mlock.c, ACTION_AGAIN > 2. migrate_device.c, goto again array overrun / double counting > 3. migrate_device.c, softleaf_to_folio VM_WARN > 4. migrate_device.c, pte_pfn / pte_dirty on non-present PTE > > I think issue 4 is real issue, a quick fix is > > diff --git a/mm/migrate_device.c b/mm/migrate_device.c > index 554754eb26ff..3ccc4fc1015c 100644 > --- a/mm/migrate_device.c > +++ b/mm/migrate_device.c > @@ -401,7 +401,8 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp, >                         bool anon_exclusive; >                         pte_t swp_pte; > > -                       flush_cache_page(vma, addr, pte_pfn(pte)); > +                       if (pte_present(pte)) > +                               flush_cache_page(vma, addr, pte_pfn(pte)); >                         anon_exclusive = folio_test_anon(folio) && >                                           PageAnonExclusive(page); That looks reasonable. >                         if (anon_exclusive) { > @@ -422,8 +423,12 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp, >                         migrate->cpages++; > >                         /* Set the dirty flag on the folio now the pte is gone. */ > -                       if (pte_dirty(pte)) > +                       if (pte_present(pte)) { > +                               if (pte_dirty(pte)) > +                                       folio_mark_dirty(folio); > +                       } else if (softleaf_is_device_private_write(entry)) { >                                 folio_mark_dirty(folio); > +                       } The pte_presnt() check looks reasonable. But dirty handling is really responsibility of the device side user. So likely just if (pte_present(pte) && pte_dirty(pte)) folio_mark_dirty(folio); -- Cheers, David