Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755993AbdGCOPD (ORCPT ); Mon, 3 Jul 2017 10:15:03 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:37024 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933128AbdGCNpx (ORCPT ); Mon, 3 Jul 2017 09:45:53 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Doug Berger , Mark Rutland , Russell King Subject: [PATCH 4.9 150/172] ARM: 8685/1: ensure memblock-limit is pmd-aligned Date: Mon, 3 Jul 2017 15:35:30 +0200 Message-Id: <20170703133421.351084498@linuxfoundation.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170703133414.260777365@linuxfoundation.org> References: <20170703133414.260777365@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2021 Lines: 56 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Doug Berger commit 9e25ebfe56ece7541cd10a20d715cbdd148a2e06 upstream. The pmd containing memblock_limit is cleared by prepare_page_table() which creates the opportunity for early_alloc() to allocate unmapped memory if memblock_limit is not pmd aligned causing a boot-time hang. Commit 965278dcb8ab ("ARM: 8356/1: mm: handle non-pmd-aligned end of RAM") attempted to resolve this problem, but there is a path through the adjust_lowmem_bounds() routine where if all memory regions start and end on pmd-aligned addresses the memblock_limit will be set to arm_lowmem_limit. Since arm_lowmem_limit can be affected by the vmalloc early parameter, the value of arm_lowmem_limit may not be pmd-aligned. This commit corrects this oversight such that memblock_limit is always rounded down to pmd-alignment. Fixes: 965278dcb8ab ("ARM: 8356/1: mm: handle non-pmd-aligned end of RAM") Signed-off-by: Doug Berger Suggested-by: Mark Rutland Signed-off-by: Russell King Signed-off-by: Greg Kroah-Hartman --- arch/arm/mm/mmu.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -1211,15 +1211,15 @@ void __init adjust_lowmem_bounds(void) high_memory = __va(arm_lowmem_limit - 1) + 1; + if (!memblock_limit) + memblock_limit = arm_lowmem_limit; + /* * Round the memblock limit down to a pmd size. This * helps to ensure that we will allocate memory from the * last full pmd, which should be mapped. */ - if (memblock_limit) - memblock_limit = round_down(memblock_limit, PMD_SIZE); - if (!memblock_limit) - memblock_limit = arm_lowmem_limit; + memblock_limit = round_down(memblock_limit, PMD_SIZE); if (!IS_ENABLED(CONFIG_HIGHMEM) || cache_is_vipt_aliasing()) { if (memblock_end_of_DRAM() > arm_lowmem_limit) {