From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757488AbcKBVBG (ORCPT ); Wed, 2 Nov 2016 17:01:06 -0400 Received: from mail-qt0-f173.google.com ([209.85.216.173]:36788 "EHLO mail-qt0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757470AbcKBVBE (ORCPT ); Wed, 2 Nov 2016 17:01:04 -0400 From: Laura Abbott To: Marek Szyprowski , Joonsoo Kim , Mark Rutland , Ard Biesheuvel , Will Deacon , Catalin Marinas Cc: Laura Abbott , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , linux-arm-kernel@lists.infradead.org Subject: [PATCHv2 2/6] mm/cma: Cleanup highmem check Date: Wed, 2 Nov 2016 15:00:50 -0600 Message-Id: <20161102210054.16621-3-labbott@redhat.com> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20161102210054.16621-1-labbott@redhat.com> References: <20161102210054.16621-1-labbott@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 6b101e2a3ce4 ("mm/CMA: fix boot regression due to physical address of high_memory") added checks to use __pa_nodebug on x86 since CONFIG_DEBUG_VIRTUAL complains about high_memory not being linearlly mapped. arm64 is now getting support for CONFIG_DEBUG_VIRTUAL as well. Rather than add an explosion of arches to the #ifdef, switch to an alternate method to calculate the physical start of highmem using the page before highmem starts. This avoids the need for the #ifdef and extra __pa_nodebug calls. Signed-off-by: Laura Abbott --- mm/cma.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/mm/cma.c b/mm/cma.c index 384c2cb..71a2ec1 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -235,18 +235,13 @@ int __init cma_declare_contiguous(phys_addr_t base, phys_addr_t highmem_start; int ret = 0; -#ifdef CONFIG_X86 /* - * high_memory isn't direct mapped memory so retrieving its physical - * address isn't appropriate. But it would be useful to check the - * physical address of the highmem boundary so it's justifiable to get - * the physical address from it. On x86 there is a validation check for - * this case, so the following workaround is needed to avoid it. + * We can't use __pa(high_memory) directly, since high_memory + * isn't a valid direct map VA, and DEBUG_VIRTUAL will (validly) + * complain. Find the boundary by adding one to the last valid + * address. */ - highmem_start = __pa_nodebug(high_memory); -#else - highmem_start = __pa(high_memory); -#endif + highmem_start = __pa(high_memory - 1) + 1; pr_debug("%s(size %pa, base %pa, limit %pa alignment %pa)\n", __func__, &size, &base, &limit, &alignment); -- 2.10.1