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 37BFC47ACF0; Sat, 12 Sep 2026 12:01:56 +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=1789214517; cv=none; b=pNvwmuNYBcNlzr09+W+YXyC7dit6m2sFKmL1R+lOXPjYepUUxdfMCL4Kz7y2qVeN8f7WniRVJeEolPvId/US8z0xrJK6Ty45O+/tWyuBW0yyV07aZnASNcl5dnkkkNjtif0htwFZYMdwJ8OLZbvBuy9f8+VHy8Gxnun3x+Ru6cE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789214517; c=relaxed/simple; bh=f1KnR8+/QDikHd8TMHNY2kUmM4V3QN3BTC8PBQ87BKw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=raHreXXYOnvLffde0D9UFqEsDrvUiflHkDvwjgYwAskIeldpn0dkWQIgdbatRjNa6AObEJYXYufVn/Y4SomXwodr+m/SmR9QfjqNR7F9AP7MkhCjRqT7TrXPuIA9h6QB1T67sjHzVwYRAvqbvkWTuwLzzobIiExZ5hYb1d6C+zc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ABhgCzwH; 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="ABhgCzwH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 29C641F000FF; Sat, 12 Sep 2026 12:01:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789214516; bh=krsYG1MBu7f/5DjFaVnr+z1EqbnY23h29dY+kEaaPwQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ABhgCzwHVuym0MgDHgUF8AL2jfzqJAhkHStVINiKUkcoTKdD4IPSrd5hO8EJikPS3 2wGjPPPIf98Ftd5hpjXoT8q7+cRIC8wvmcxhbsV9jMuAtvHgg2+xdV732PrUDrFlSu YoaKc97IiFS7g0o8ElCNIW7m3BGLzrTo9VXHn81M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wei Yang , Yuan Liu , "Mike Rapoport (Microsoft)" , Sasha Levin Subject: [PATCH 6.12 0343/1376] mm/mm_init: fix incorrect node_spanned_pages Date: Sat, 12 Sep 2026 08:46:09 +0200 Message-ID: <20260912065615.196607320@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.535295758@linuxfoundation.org> References: <20260912065607.535295758@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wei Yang [ Upstream commit 7783dcd79ae9c4aa48bc47bd4275772445dc4b2a ] Current node_spanned_pages is got as a summation of all zone's spanned page in calculate_node_totalpages(). Generally this is good, but if we use kernelcore=mirror, it is would be wrong. Without kernelcore=mirror: The test machine has below memory layout: memory[0x0] [0x0000000000001000-0x000000000009efff], 0x000000000009e000 bytes on node 0 flags: 0x0 memory[0x1] [0x0000000000100000-0x00000000bffdefff], 0x00000000bfedf000 bytes on node 0 flags: 0x0 memory[0x2] [0x0000000100000000-0x00000001bfffffff], 0x00000000c0000000 bytes on node 0 flags: 0x0 And the Zone range is: DMA [mem 0x0000000000001000-0x0000000000ffffff] DMA32 [mem 0x0000000001000000-0x00000000ffffffff] Normal [mem 0x0000000100000000-0x00000001bfffffff] Then we see, with spanned_pages printed: On node 0 spanned_pages: 1835007 totalpages: 1572733 With kernelcore=mirror: The test machine has below memory layout: memory[0x0] [0x0000000000001000-0x000000000009efff], 0x000000000009e000 bytes on node 0 flags: 0x2 memory[0x1] [0x0000000000100000-0x00000000bffdefff], 0x00000000bfedf000 bytes on node 0 flags: 0x2 memory[0x2] [0x0000000100000000-0x000000013fffffff], 0x0000000040000000 bytes on node 0 flags: 0x2 memory[0x3] [0x0000000140000000-0x00000001bfffffff], 0x0000000080000000 bytes on node 0 flags: 0x0 And the Zone range is: DMA [mem 0x0000000000001000-0x0000000000ffffff] DMA32 [mem 0x0000000001000000-0x00000000ffffffff] Normal [mem 0x0000000100000000-0x00000001bfffffff] Device empty Movable zone start for each node Node 0: 0x0000000140000000 Then we see, with spanned_pages printed: On node 0 spanned_pages: 2359295 totalpages: 1572733 The total range of memory on node 0 doesn't change, but the spanned_pages becomes much larger. The reason is when kernelcore=mirror is specified, the range of Zone Normal and Zone Movable would overlap. So the overlapped range would be calculated twice. A wrong node_spanned_pages would effect defer_init(), since each zone_end_pfn is less than pgdat_end_pfn(). As we already passed in node_start_pfn and node_end_pfn, fix this by get it from (node_start_pfn - node_end_pfn) directly. Fixes: 342332e6a925 ("mm/page_alloc.c: introduce kernelcore=mirror option") Signed-off-by: Wei Yang Cc: Yuan Liu Link: https://patch.msgid.link/20260622022403.16375-1-richard.weiyang@gmail.com Signed-off-by: Mike Rapoport (Microsoft) Signed-off-by: Sasha Levin --- mm/mm_init.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/mm/mm_init.c b/mm/mm_init.c index 21e01537c9f5f..c8ac7f206f941 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -1310,7 +1310,7 @@ static void __init calculate_node_totalpages(struct pglist_data *pgdat, unsigned long node_start_pfn, unsigned long node_end_pfn) { - unsigned long realtotalpages = 0, totalpages = 0; + unsigned long realtotalpages = 0; enum zone_type i; for (i = 0; i < MAX_NR_ZONES; i++) { @@ -1340,11 +1340,10 @@ static void __init calculate_node_totalpages(struct pglist_data *pgdat, zone->present_early_pages = real_size; #endif - totalpages += spanned; realtotalpages += real_size; } - pgdat->node_spanned_pages = totalpages; + pgdat->node_spanned_pages = node_end_pfn - node_start_pfn; pgdat->node_present_pages = realtotalpages; pr_debug("On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages); } -- 2.53.0