From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6C5A2606A323 for ; Wed, 28 Oct 2026 08:26:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=tK8FPKJ7 Received: by kanga.kvack.org (Postfix) id 7792C6B05B1; Wed, 28 Oct 2026 04:26:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 751886B05B2; Wed, 28 Oct 2026 04:26:26 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 640056B05BC; Wed, 28 Oct 2026 04:26:26 -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 3F7836B05B1 for ; Wed, 28 Oct 2026 04:26:26 -0400 (EDT) Received: from smtpin19.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id C7584A89E0 for ; Wed, 28 Oct 2026 08:26:25 +0000 (UTC) X-FDA: 85371353130.19.310FA40 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf16.hostedemail.com (Postfix) with ESMTP id E40A9180008 for ; Wed, 28 Oct 2026 08:26:23 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b=tK8FPKJ7; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf16.hostedemail.com: domain of dev.jain@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=dev.jain@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793175984; 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=ZqxvUOYEnw6epSxNJkOsH/iPXoP3tG6fnt6qx+16CDI=; b=iNT+lv0hPK2d+FD6d+o5gSxeC/qXy1xXR1G99DyOCaYcM4QgwFg1V/gBw7iT7Ljc3wmkyQ RmXsSXiLzcvq1PQa8Eeysecui5ib8tdZG5+AAbLiETX99KqtUusGN1jfTcQGMfksV5zPub 299Pai5aBJZPCEAr1kK+OSF9LUnoOQ8= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b=tK8FPKJ7; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf16.hostedemail.com: domain of dev.jain@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=dev.jain@arm.com ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793175984; b=WG6Z49bjC6hoI+UQ7CuFc5MZNomCWWze3MAe2H7ht0P5VRnF9IWtfTKxGdCkYcWbhkvTSN SpZTkHXaMewYHPZoMZfaJy3mnMkVcN3X31Ea5hh6F3YmcaoC/DnrBWUTNAhS+IeyvEjNTT gVGY7ykUo4xzQSeBqp1uDunXqCIvfnQ= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6ECF2175D; Wed, 28 Oct 2026 01:26:19 -0700 (PDT) Received: from [10.163.164.200] (unknown [10.163.164.200]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7FA7C3F7B4; Wed, 28 Oct 2026 01:26:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1793175982; bh=/EbjTDVkdW0F57Y0gRKQi9v+oLhQOt+D3xEeKM70nII=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=tK8FPKJ775LMj/HKo8mObMmx6qKh5HiYiCirC0X5N+Uj94ZXLcgBO0gJmsuhWRb4A Le1KG8SJsaJkW/YAWbL9G7bsI6/KPkhwkETh7gUgwJbaEDX8Eg/t78/F2JU1nNSeDl jDJpfCYMNVh0lVMDuVYpKwlU4CCZEtAy7DaSDSSM= Message-ID: <50f426ea-7477-4fb4-a520-0d7fe4b84c37@arm.com> Date: Wed, 28 Oct 2026 13:55:59 +0530 X-Archived-By: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 14/46] mm/huge_memory: fix zapping migration entries for device-private THPs To: "David Hildenbrand (Arm)" , Andrew Morton , Johannes Weiner , Michal Hocko , Qi Zheng , Shakeel Butt , Lorenzo Stoakes , Kairui Song , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baoquan He , Baolin Wang , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kees Cook , Peter Zijlstra , Jann Horn , Pedro Falcato , Hugh Dickins , Pasha Tatashin , Pratyush Yadav , "Matthew Wilcox (Oracle)" , Jan Kara , Zi Yan , Lance Yang , Rik van Riel , Harry Yoo , Alistair Popple , Nico Pache , Ryan Roberts , Usama Arif , Kiryl Shutsemau , Matthew Brost , John Hubbard , Peter Xu , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Oscar Salvador , Minchan Kim , Muchun Song , Xu Xin , Chengming Zhou , Chris Li , Kemeng Shi , Nhat Pham , Youngjun Park , Gregory Price , Joshua Hahn , Rakie Kim , Ying Huang , Jason Gunthorpe Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-cxl@vger.kernel.org, Chris Mason , stable@vger.kernel.org References: <20261027-fixes_core-v1-0-6f74bec9a5bb@kernel.org> <20261027-fixes_core-v1-14-6f74bec9a5bb@kernel.org> Content-Language: en-US From: Dev Jain In-Reply-To: <20261027-fixes_core-v1-14-6f74bec9a5bb@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: E40A9180008 X-Stat-Signature: ka3ojkh8eoaf1ziinnhg3hasbwyr6hqg X-Spam-Status: No, score=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=4.0.1 X-Rspam-User: X-HE-Tag: 1793175983-175384 X-HE-Meta: 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 s+B+vXbX t38/A2XafznCzut6XQti6ioD+6WQAhSSS0V5nT9uK5gaMcB3/+F5bMJFkmeV8EIalvkcpx1nNxotzrcy3zTpFSHFPv8fUnR5USZtyLKdPaZKKd1vyuFHyHF2Kc2+tcD4X3yQG1ip/yjveTajO4cmo3pWHgdFh1NwjaTiiHmBTNfKhlhnkqlSicuyFznZ4Aohcz+G6rwyxT54iXpPgpifKxSt7u8EeR0Z8dlPRkT5l/inxK7O5obzUvQbs2e0/F2r2TXiJvjZDo8VMl1udKyRpvhHvjwkhGH/R1zZy52LePWKt8+Ke4dx+BYKjlvLkhAxrefZPT9LmRd1cilk0DAXq968MbanlfkM2+Xm7iT/QmFwmh1pWkYYb1PdrKwDTwDNqnmaXd8/GEZhqOyQX0K1RZ2Wvl/I9MAwbDCCnXBSf19ZQyBqjMzJdxBr/Nw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 27/10/26 4:47 am, David Hildenbrand (Arm) wrote: > From: Chris Mason > > A PMD migration entry can refer to a device-private folio. > zap_huge_pmd_folio() checks the folio type instead of the entry type, > so it treats such a migration entry as a device-private entry. > > Installing the migration entry already removed the reverse mapping and > dropped the mapping reference. Zapping it must not repeat those > operations. Concurrent MADV_DONTNEED during migration back to system > memory can trigger this. > > Check the PMD entry type using pmd_is_device_private_entry(). > > Fix generated by an LLM and sent by Chris Mason in private. > > Fixes: 368076f52ebe ("mm/huge_memory: add device-private THP support to PMD operations") > Cc: stable@vger.kernel.org > Signed-off-by: Chris Mason > [ david: simplify description ] > Signed-off-by: David Hildenbrand (Arm) > --- Matches zap_nonpresent_ptes. Reviewed-by: Dev Jain > mm/huge_memory.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index eda020dd6e33f..1b50cc2b35351 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -2493,7 +2493,7 @@ static inline void zap_deposited_table(struct mm_struct *mm, pmd_t *pmd) > static void zap_huge_pmd_folio(struct mm_struct *mm, struct vm_area_struct *vma, > pmd_t pmdval, struct folio *folio, bool is_present) > { > - const bool is_device_private = folio_is_device_private(folio); > + const bool is_device_private = !is_present && pmd_is_device_private_entry(pmdval); > > /* Transfer young+dirty while the folio is still mapped. */ > if (is_present && !folio_test_anon(folio)) { >