From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DEE0B357D14; Tue, 16 Jun 2026 15:33:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781624010; cv=none; b=PMF1Qi0CVcl+ukUXmMZY7kILdHk3H75aj1/DPCwpZfaTBw9CaI5x8tSjohIHUVc4hpIyS0JSKdaZNgE8yz3xejSONlAlChaLqIAoNR6/jv7rP+i6IsvRZY9VeGZVCFoXZS0fpcYlO49v6kYoVO5y3C9ZikVpqoj9lZe+O0ZR3b0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781624010; c=relaxed/simple; bh=0Ka5c85E/v+cYfER3ln3ug3ecyBt4naL1RP5M2yBHqk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ffpWMiL5VyTNsedldJSL3WS2sfshmiEo416rwFEtTWEhP1GI5aZGKDh/A0eVS5E1a3swsgwr+d/93d3RmyWMf/3jij8RvwWh+c/aUWFZSwDUR9VCAog3ImlbO2UaHStbWaOWLAMJ7LgyiPn2ORQ1Io2aIiBZT9p9Ky9Xbybf7ks= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qvuw2nyV; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="qvuw2nyV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E5C511F000E9; Tue, 16 Jun 2026 15:33:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781624009; bh=psJF92ZTkJKqlQaFWM9bmaLN0/jN5A4LhvufK6QDHOo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=qvuw2nyV3oyUpyXyNcD+CrgkeEwFKF5KYvSgILrrQS25qo8z66g6CnzazyrPF964D vSHmpGyu1B/dEXbFDbRyq8/XiRnqWv1GSNupAuQCOgcYjvEExaeACKgielghXSxUJK BcKz5H9M5TbqFLfzYnnW+JE5CXH5yLAg4zUXD6/U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alistair Popple , Catalin Marinas , David Hildenbrand , Will Deacon , Andrew Morton Subject: [PATCH 7.0 229/378] arm64: mm: call pagetable dtor when freeing hot-removed page tables Date: Tue, 16 Jun 2026 20:27:40 +0530 Message-ID: <20260616145122.328768376@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145109.744539446@linuxfoundation.org> References: <20260616145109.744539446@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alistair Popple commit c594b83457ccdee76d458416fb3bc9348a37592f upstream. Since 5e8eb9aeeda3 ("arm64: mm: always call PTE/PMD ctor in __create_pgd_mapping()") page-table allocation on ARM64 always calls pagetable_{pte,pmd,pud,p4d}_ctor(). This sets the page_type to PGTY_table, increments NR_PAGETABLE and possible allocates a PTL. However the matching pagetable_dtor() calls were never added. With DEBUG_VM enabled on kernel versions prior to v6.17 without 2dfcd1608f3a9 ("mm/page_alloc: let page freeing clear any set page type") this leads to the following warning when freeing these pages due to page->page_type sharing page->_mapcount: BUG: Bad page state in process ... pfn:284fbb page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x284fbb flags: 0x17fffc000000000(node=0|zone=2|lastcpupid=0x1ffff) page_type: f2(table) page dumped because: nonzero mapcount Call trace: bad_page+0x13c/0x160 __free_frozen_pages+0x6cc/0x860 ___free_pages+0xf4/0x180 free_pages+0x54/0x80 free_hotplug_page_range.part.0+0x58/0x90 free_empty_tables+0x438/0x500 __remove_pgd_mapping.constprop.0+0x60/0xa8 arch_remove_memory+0x48/0x80 try_remove_memory+0x158/0x1d8 offline_and_remove_memory+0x138/0x180 It can also lead to leaking the ptl allocation if ALLOC_SPLIT_PTLOCKS is defined and incorrect NR_PAGETABLE stats. Fix this by calling pagetable_dtor() in free_hotplug_pgtable_page() prior to freeing the page to undo the effects of calling pagetable_*_ctor(). Link: https://lore.kernel.org/20260521032730.2104017-1-apopple@nvidia.com Fixes: 5e8eb9aeeda3 ("arm64: mm: always call PTE/PMD ctor in __create_pgd_mapping()") Signed-off-by: Alistair Popple Cc: Catalin Marinas Cc: David Hildenbrand Cc: Will Deacon Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- arch/arm64/mm/mmu.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -1445,6 +1445,7 @@ static void free_hotplug_page_range(stru static void free_hotplug_pgtable_page(struct page *page) { + pagetable_dtor(page_ptdesc(page)); free_hotplug_page_range(page, PAGE_SIZE, NULL); }