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 634602F7F01; Wed, 7 Oct 2026 00:52:06 +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=1791334327; cv=none; b=q+jyEEWt5m+ZZk6YKfuS+Bai7tFP0Sf1MfSmISIGrkFU3nDM0nKnXgL1W0cb2AwsmAvxYgRBHGZsJhQJLRbT14DRYX5AiF1GIV/0IOpWW9JP55he7CKbhGosT3KQNQoFHbWarlPnPgjRrNyp7WqImS+7DH0r4NUdfRLJkJQtMKE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791334327; c=relaxed/simple; bh=LOhu/qpeb2fnALucy46mPwI1UuV80iSA2i5iSb8PM64=; h=Date:To:From:Subject:Message-Id; b=PzNxp8h6z8tNqeXcbFEO+vBnM+0ECkkLtpZZDOwZAV2X2SqJ8OiiGm/F9BXhw5dDd9HGMgDD01cjxJHqQHVeTHO8JQKEnY6D8bJQyzW5rNfxeIEyQSrMRrNMscM/Wccy8ZPP/B7V38s3mNSPm8NrCe2leJnYX0aePzP1Wn56H3M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=LGWOWnYD; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="LGWOWnYD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38CB41F008A3; Wed, 7 Oct 2026 00:52:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1791334326; bh=FLyM1HRxah/6l4q2JRzLvBXNhnByqSohY/OoyaVralY=; h=Date:To:From:Subject; b=LGWOWnYDBljWAWs5GStdXuwVLeqjweIoUuLVtfWGV/8XpxBwlsfJZF1ULVJeNNSCa q2FGOEwVfGQi6OQObGz+l4u72adpfk0K40R5XgZ+W+I3xv9yRM7uNqpA0Mvo0xk4wa DMM4jovHUlcf+oKYApVg4eJKqSJjqRXcmlxzllNk= Date: Tue, 06 Oct 2026 17:52:05 -0700 To: mm-commits@vger.kernel.org,vega@nebusec.ai,stable@vger.kernel.org,liuye@kylinos.cn,enjou1224z@gmail.com,roxy520tt@gmail.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-page_table_check-skip-zero-pages.patch removed from -mm tree Message-Id: <20261007005206.38CB41F008A3@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/page_table_check: skip zero pages has been removed from the -mm tree. Its filename was mm-page_table_check-skip-zero-pages.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Zhiling Zou Subject: mm/page_table_check: skip zero pages Date: Tue, 21 Jul 2026 23:56:38 +0800 page_table_check_set() accounts pages by whether they are PageAnon(). The shared zero page is a special page, not an ordinary file-backed page. Read faults on private anonymous mappings can install many read-only PTEs that point at the zero page, but page_table_check currently accounts them in file_map_count. That lets an unprivileged process populate enough zero-page mappings to overflow file_map_count and trip the BUG_ON() in page_table_check_set(). Skip zero pages in page_table_check accounting. They do not need the anonymous/file mapping conflict checks that page_table_check performs for ordinary pages, and this keeps the existing counter size and page_ext layout unchanged. Link: https://lore.kernel.org/1f8848512d2e3ded944f8d595c29faee8fdaeab0.1784645969.git.roxy520tt@gmail.com Fixes: df4e817b7108 ("mm: page table check") Signed-off-by: Zhiling Zou Signed-off-by: Ren Wei Signed-off-by: Andrew Morton Reported-by: Vega Assisted-by: Codex:gpt-5.4 Cc: Ye Liu Cc: --- mm/page_table_check.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/page_table_check.c~mm-page_table_check-skip-zero-pages +++ a/mm/page_table_check.c @@ -67,7 +67,7 @@ static void page_table_check_clear(unsig struct page *page; bool anon; - if (!pfn_valid(pfn)) + if (!pfn_valid(pfn) || is_zero_pfn(pfn) || is_huge_zero_pfn(pfn)) return; page = pfn_to_page(pfn); @@ -102,7 +102,7 @@ static void page_table_check_set(unsigne struct page *page; bool anon; - if (!pfn_valid(pfn)) + if (!pfn_valid(pfn) || is_zero_pfn(pfn) || is_huge_zero_pfn(pfn)) return; page = pfn_to_page(pfn); _ Patches currently in -mm which might be from roxy520tt@gmail.com are