From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 79036C55178 for ; Fri, 30 Oct 2020 18:11:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BC5A622283 for ; Fri, 30 Oct 2020 18:11:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BC5A622283 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 95A126B0036; Fri, 30 Oct 2020 14:11:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 902C06B005C; Fri, 30 Oct 2020 14:11:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 735206B005D; Fri, 30 Oct 2020 14:11:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0207.hostedemail.com [216.40.44.207]) by kanga.kvack.org (Postfix) with ESMTP id 3C6506B0036 for ; Fri, 30 Oct 2020 14:11:43 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id CC0C133C4 for ; Fri, 30 Oct 2020 18:11:42 +0000 (UTC) X-FDA: 77429384844.21.kitty99_2d16df827298 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin21.hostedemail.com (Postfix) with ESMTP id 9FAA1180442C3 for ; Fri, 30 Oct 2020 18:11:42 +0000 (UTC) X-HE-Tag: kitty99_2d16df827298 X-Filterd-Recvd-Size: 4410 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf18.hostedemail.com (Postfix) with ESMTP for ; Fri, 30 Oct 2020 18:11:41 +0000 (UTC) Received: from gaia (unknown [95.145.162.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D3A17206E5; Fri, 30 Oct 2020 18:11:37 +0000 (UTC) Date: Fri, 30 Oct 2020 18:11:35 +0000 From: Catalin Marinas To: Nicolas Saenz Julienne Cc: robh+dt@kernel.org, hch@lst.de, ardb@kernel.org, linux-kernel@vger.kernel.org, robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org, linux-rpi-kernel@lists.infradead.org, jeremy.linton@arm.com, iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, will@kernel.org, lorenzo.pieralisi@arm.com, guohanjun@huawei.com, linux-acpi@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v5 0/7] arm64: Default to 32-bit wide ZONE_DMA Message-ID: <20201030181134.GE23196@gaia> References: <20201029172550.3523-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201029172550.3523-1-nsaenzjulienne@suse.de> User-Agent: Mutt/1.10.1 (2018-07-13) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Oct 29, 2020 at 06:25:43PM +0100, Nicolas Saenz Julienne wrote: > Ard Biesheuvel (1): > arm64: mm: Set ZONE_DMA size based on early IORT scan > > Nicolas Saenz Julienne (6): > arm64: mm: Move reserve_crashkernel() into mem_init() > arm64: mm: Move zone_dma_bits initialization into zone_sizes_init() > of/address: Introduce of_dma_get_max_cpu_address() > of: unittest: Add test for of_dma_get_max_cpu_address() > arm64: mm: Set ZONE_DMA size based on devicetree's dma-ranges > mm: Remove examples from enum zone_type comment Thanks for putting this together. I had a minor comment but the patches look fine to me. We still need an ack from Rob on the DT patch and I can queue the series for 5.11. Could you please also test the patch below on top of this series? It's the removal of the implied DMA offset in the max_zone_phys() calculation. --------------------------8<----------------------------- >From 3ae252d888be4984a612236124f5b099e804c745 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Fri, 30 Oct 2020 18:07:34 +0000 Subject: [PATCH] arm64: Ignore any DMA offsets in the max_zone_phys() calculation Currently, the kernel assumes that if RAM starts above 32-bit (or zone_bits), there is still a ZONE_DMA/DMA32 at the bottom of the RAM and such constrained devices have a hardwired DMA offset. In practice, we haven't noticed any such hardware so let's assume that we can expand ZONE_DMA32 to the available memory if no RAM below 4GB. Similarly, ZONE_DMA is expanded to the 4GB limit if no RAM addressable by zone_bits. Signed-off-by: Catalin Marinas --- arch/arm64/mm/init.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 095540667f0f..362160e16fb2 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -175,14 +175,21 @@ static void __init reserve_elfcorehdr(void) #endif /* CONFIG_CRASH_DUMP */ /* - * Return the maximum physical address for a zone with a given address size - * limit. It currently assumes that for memory starting above 4G, 32-bit - * devices will use a DMA offset. + * Return the maximum physical address for a zone accessible by the given bits + * limit. If the DRAM starts above 32-bit, expand the zone to the maximum + * available memory, otherwise cap it at 32-bit. */ static phys_addr_t __init max_zone_phys(unsigned int zone_bits) { - phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, zone_bits); - return min(offset + (1ULL << zone_bits), memblock_end_of_DRAM()); + phys_addr_t zone_mask = (1ULL << zone_bits) - 1; + phys_addr_t phys_start = memblock_start_of_DRAM(); + + if (!(phys_start & U32_MAX)) + zone_mask = PHYS_ADDR_MAX; + else if (!(phys_start & zone_mask)) + zone_mask = U32_MAX; + + return min(zone_mask + 1, memblock_end_of_DRAM()); } static void __init zone_sizes_init(unsigned long min, unsigned long max)