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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 C3E06C4338F for ; Tue, 3 Aug 2021 18:05:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A1F4D6105A for ; Tue, 3 Aug 2021 18:05:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238628AbhHCSFv (ORCPT ); Tue, 3 Aug 2021 14:05:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:52728 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233498AbhHCSFu (ORCPT ); Tue, 3 Aug 2021 14:05:50 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2E36260F48; Tue, 3 Aug 2021 18:05:34 +0000 (UTC) Date: Tue, 3 Aug 2021 19:05:26 +0100 From: Catalin Marinas To: Mike Rapoport Cc: Andrew Morton , Albert Ou , Andy Lutomirski , Borislav Petkov , Christian Borntraeger , Dave Hansen , Frank Rowand , Greg Kroah-Hartman , "H. Peter Anvin" , Heiko Carstens , Ingo Molnar , "Kirill A. Shutemov" , Len Brown , Marc Zyngier , Mike Rapoport , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , "Rafael J. Wysocki" , Rob Herring , Russell King , Thomas Bogendoerfer , Thomas Gleixner , Vasily Gorbik , Will Deacon , devicetree@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v3] memblock: make memblock_find_in_range method private Message-ID: <20210803180526.GD5786@arm.com> References: <20210803064218.6611-1-rppt@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210803064218.6611-1-rppt@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Tue, Aug 03, 2021 at 09:42:18AM +0300, Mike Rapoport wrote: > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index 8490ed2917ff..0bffd2d1854f 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -74,6 +74,7 @@ phys_addr_t arm64_dma_phys_limit __ro_after_init; > static void __init reserve_crashkernel(void) > { > unsigned long long crash_base, crash_size; > + unsigned long long crash_max = arm64_dma_phys_limit; > int ret; > > ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), > @@ -84,33 +85,18 @@ static void __init reserve_crashkernel(void) > > crash_size = PAGE_ALIGN(crash_size); > > - if (crash_base == 0) { > - /* Current arm64 boot protocol requires 2MB alignment */ > - crash_base = memblock_find_in_range(0, arm64_dma_phys_limit, > - crash_size, SZ_2M); > - if (crash_base == 0) { > - pr_warn("cannot allocate crashkernel (size:0x%llx)\n", > - crash_size); > - return; > - } > - } else { > - /* User specifies base address explicitly. */ > - if (!memblock_is_region_memory(crash_base, crash_size)) { > - pr_warn("cannot reserve crashkernel: region is not memory\n"); > - return; > - } > + /* User specifies base address explicitly. */ > + if (crash_base) > + crash_max = crash_base + crash_size; > > - if (memblock_is_region_reserved(crash_base, crash_size)) { > - pr_warn("cannot reserve crashkernel: region overlaps reserved memory\n"); > - return; > - } > - > - if (!IS_ALIGNED(crash_base, SZ_2M)) { > - pr_warn("cannot reserve crashkernel: base address is not 2MB aligned\n"); > - return; > - } > + /* Current arm64 boot protocol requires 2MB alignment */ > + crash_base = memblock_phys_alloc_range(crash_size, SZ_2M, > + crash_base, crash_max); > + if (!crash_base) { > + pr_warn("cannot allocate crashkernel (size:0x%llx)\n", > + crash_size); > + return; > } > - memblock_reserve(crash_base, crash_size); We'll miss a bit on debug information provided to the user in case of a wrong crash_base/size option on the command line. Not sure we care much, though the alignment would probably be useful (maybe we document it somewhere). What I haven't checked is whether memblock_phys_alloc_range() aims to get a 2MB aligned end (size) as well. If crash_size is not 2MB aligned, crash_max wouldn't be either and the above could fail. We only care about the crash_base to be aligned but the memblock_phys_alloc_range() doc says that both the start and size would be aligned to this. -- Catalin