From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id AFD176B0269 for ; Tue, 3 Jul 2018 17:10:56 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id h14-v6so1596471pfi.19 for ; Tue, 03 Jul 2018 14:10:56 -0700 (PDT) Received: from mga17.intel.com (mga17.intel.com. [192.55.52.151]) by mx.google.com with ESMTPS id a1-v6si1893157plp.247.2018.07.03.14.10.55 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Jul 2018 14:10:55 -0700 (PDT) Subject: [PATCH] x86/numa_emulation: Fix uniform size build failure From: Dan Williams Date: Tue, 03 Jul 2018 14:00:57 -0700 Message-ID: <153065162801.12250.4860144566061573514.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: mingo@kernel.org Cc: David Rientjes , Thomas Gleixner , Wei Yang , kbuild test robot , x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org The calculation of a uniform numa-node size attempted to perform division with a 64-bit diviser leading to the following failure on 32-bit: arch/x86/mm/numa_emulation.o: In function `split_nodes_size_interleave_uniform': arch/x86/mm/numa_emulation.c:239: undefined reference to `__udivdi3' Convert the implementation to do the division in terms of pages and then shift the result back to an absolute physical address. Fixes: 93e738834fcc ("x86/numa_emulation: Introduce uniform split capability") Cc: David Rientjes Cc: Thomas Gleixner Cc: Wei Yang Reported-by: kbuild test robot Signed-off-by: Dan Williams --- Applies to tip/x86/cpu for 4.19. arch/x86/mm/numa_emulation.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c index 039db00541b7..cc7523e45926 100644 --- a/arch/x86/mm/numa_emulation.c +++ b/arch/x86/mm/numa_emulation.c @@ -198,6 +198,14 @@ static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size) return end; } +static u64 uniform_size(u64 max_addr, u64 base, int nr_nodes) +{ + unsigned long max_pfn = PHYS_PFN(max_addr); + unsigned long base_pfn = PHYS_PFN(base); + + return PFN_PHYS((max_pfn - base_pfn) / nr_nodes); +} + /* * Sets up fake nodes of `size' interleaved over physical nodes ranging from * `addr' to `max_addr'. @@ -236,7 +244,7 @@ static int __init split_nodes_size_interleave_uniform(struct numa_meminfo *ei, } if (uniform) { - min_size = (max_addr - addr) / nr_nodes; + min_size = uniform_size(max_addr, addr, nr_nodes); size = min_size; } else { /*