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 DDA2A606A32D for ; Thu, 29 Oct 2026 20:40:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=BizzfTpX Received: by kanga.kvack.org (Postfix) id 029216B05DF; Thu, 29 Oct 2026 16:40:56 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 000616B05E0; Thu, 29 Oct 2026 16:40:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E59EA6B05E1; Thu, 29 Oct 2026 16:40:55 -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 BEC556B05DF for ; Thu, 29 Oct 2026 16:40:55 -0400 (EDT) Received: from smtpin25.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 566ED8031A for ; Thu, 29 Oct 2026 20:40:55 +0000 (UTC) X-FDA: 85376832870.25.39DE9BD Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf09.hostedemail.com (Postfix) with ESMTP id 7615A14000D for ; Thu, 29 Oct 2026 20:40:53 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=BizzfTpX; spf=pass (imf09.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 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=1793306453; b=cmIyvSGNXrlF1Hasgj1YWbNbrDT9rLiCptRZ++4p4JcTaVlZKN62Dr2lubZPTqRQx/daZl S5t10QRHUT/6h6JsmkVx0ucKTSqzb0e130vZBHxDgX7Jla5je4vWwbMs6dMQpcw/9WCBQ8 AsOek+h5rpP4cyc4U72FHPdYbPsKE80= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=BizzfTpX; spf=pass (imf09.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 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=1793306453; 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=X+A4bDZDQi3RaQKtCdHq4Q8CuoDLcygQanGTwpRAvoc=; b=NT/M707qDJTMwX9Eu4dSgFOhPx9zUUS4aM08WTfApDLk0yVZ35wfh/IDxf8aeBWfHsBFGa idZVC0vxyMYXMJcsPpA71hddDSrRhTZ+nzz96Mr/04LK/u5iwU07DPkZQj8PKCoDbmnsso /K3qo3QBDpq4s7SYaBI+nqd2YDQtO+4= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id B040A43981; Thu, 29 Oct 2026 20:40:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C7BA41F01816; Thu, 29 Oct 2026 20:40:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793306452; bh=X+A4bDZDQi3RaQKtCdHq4Q8CuoDLcygQanGTwpRAvoc=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=BizzfTpXd6POIT2VXSctKqd3AYlrKo21t0yuW7k67ZzOykQkrmsF70tvdF27m6nHR yNjzirG7yxUIMePV6cd6o6LqX0pSAl/IgEUme2KHxm9O9PpZuALo6dRUKAQxGfhH+t DA4gWLZ8yol5BW+DLrHcMvUGxusQPKgKUrtfujihDYvPnJt/TJ6tSS39u2H8P+KZTy nZoUv3JERjR/gKqqgwAYI7hfD8T9nuqpmpfN6GDlxYR++om/RP/DZmQULDWoiS4s/L v9kzIakhQuG4RHlpqlhNNq5l4cyBf7BOUkPJX3p8OED7PzmsQ16EQbSRbPchOgEa/p CExcoOfTYv/tA== From: "David Hildenbrand (Arm)" Date: Thu, 29 Oct 2026 21:33:25 +0100 Subject: [PATCH v2 30/47] mm/mremap: use pudp_huge_get_and_clear() when moving huge PUDs X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261029-fixes_core-v2-30-a64ce7f83abb@kernel.org> References: <20261029-fixes_core-v2-0-a64ce7f83abb@kernel.org> In-Reply-To: <20261029-fixes_core-v2-0-a64ce7f83abb@kernel.org> To: 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 , Dev Jain , 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, stable@vger.kernel.org, "David Hildenbrand (Arm)" X-Mailer: b4 0.16.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1293; i=david@kernel.org; h=from:subject:message-id; bh=Bwj0I+EdpwxOB+DXKGU57G1Zy0OI6QgT1Ao2qNPPN2Q=; b=owGbwMvMwCF2/OVpCdfQ3ZWMp9WSGLIer+1YqffjAfvFE1GvVCPrynaJrxGaF5yRGLK27FbyY f3NFjY8HaUsDGIcDLJiiixBwfcNXr5cV1vtxscMM4eVCWQIAxenAEzEtJDhvzePiszu11vf/Jz+ fcHuUKufNir2r8+1Gp+U2pslsLRl02qG/4lXDK3vLmCe9X8G+/cET8cdsvu85+ru1m57H2Vyc9r crywA X-Developer-Key: i=david@kernel.org; a=openpgp; fpr=1BD9CAAD735C4C3A460DFCCA4DDE10F700FF835A X-Stat-Signature: dqtjzyuu9nahm17u7sexpm979uss4nzx X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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_GIT autolearn=unavailable autolearn_force=no version=4.0.1 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 7615A14000D X-Rspam-User: X-HE-Tag: 1793306453-32435 X-HE-Meta: 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 jlfk8Gir Ctx9JKbmTEiII0mw4eOQaEDTE3NoOAQ0vbuuFs+Xg2A1mB4NOfKQZp406sHRqzAasOBkSpu1ZVEVp29F3TuyjbUQK2DlRBq26l6SAFIurUbH+sngoK0wKQxsM0YMSDHM1fVHPVZkcDnhpLsolsXFhdK6wjBCOSVlogG3gidZCJiQtGlqMb0u3NqTIs70dWFP7pPAOatxPwMU9QIJ5/zUerdvby26o02MpRk6UbYPKYTh70LiZIllB3AzFuofdSjH5ZRRWd7jpUzsAo8+utb6kQFzEP17lqQJZF4hzbWpib/Phx1BdP4LiERuxhyuv2WWFE8rDM603VwzcDN06BhFhcU9n4gcvL6aqQJhBw3RpJwzeMf0KCoAM1bYcapa07rn1Jw+kU3ujLXi/TWPubjmFIb7ukQa/kQm4xdsabfxpxtfByk4= 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 move_huge_pud() reads the old PUD and clears it in separate operations. Hardware accessed or dirty updates between those operations can be lost when the saved entry is installed at the new address. The raw pud_clear() also bypasses page_table_check_pud_clear(), while set_pud_at() accounts for the destination mapping. This leaves the checker counts unbalanced for mappings tracked by page table checking. To fix it, simply use pudp_huge_get_and_clear(). Fixes: 7d846db7d0e2 ("mm/mremap: convert huge PUD move to separate helper") Cc: stable@vger.kernel.org Reviewed-by: Lorenzo Stoakes (ARM) Reviewed-by: Pedro Falcato Reviewed-by: Dev Jain Signed-off-by: David Hildenbrand (Arm) --- mm/mremap.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/mm/mremap.c b/mm/mremap.c index 0d06d7f37f19..16e736c72d9c 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -509,8 +509,7 @@ static bool move_huge_pud(struct pagetable_move_control *pmc, spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING); /* Clear the pud */ - pud = *old_pud; - pud_clear(old_pud); + pud = pudp_huge_get_and_clear(mm, pmc->old_addr, old_pud); VM_BUG_ON(!pud_none(*new_pud)); -- 2.43.0