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=-9.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 8012BC4338F for ; Tue, 3 Aug 2021 19:10:16 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 442FB60F9C for ; Tue, 3 Aug 2021 19:10:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 442FB60F9C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=zAFpXP3MIAzRArOzXcHedLFEgsXnWOECAMMy2FtYEI4=; b=RRZ80FhCd7ijl7 /SUqWAv4L3RzfJvKMm4q+oRdoiKnf3ht+5gmJU0ln1/xVDuyQThy2jBNIVnFwKf+OBhOk50isGc75 dey4DwZvkNHCqhLvoSqiG+e2waYUlF2WoFAa2bJCKO0E7/MGMV11tyVGKc+nZuMMOkbLyY99jpnXn 5+0a6FVASn75e2meK3SGFiQxBWT4hBPVuMC72LYe6TxIL5cZQglKPssikUfMm2WdvhwEXVagy8r+X TgLqwjLJkqETRgirbCU2RHduXzfi7fmJtKWFa9TbaBMjeyuucUQhrlCy/NOGYWTfXP+z6OnLTo5h1 S5fEKiaXkXfZOp1bSDVw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mAzm3-0040lW-QY; Tue, 03 Aug 2021 19:08:23 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mAzlz-0040kN-Rq; Tue, 03 Aug 2021 19:08:21 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6758760F9C; Tue, 3 Aug 2021 19:07:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628017697; bh=+C3jjxLGYKPgJknmmGMOt0xrAE6Lm0yMyg9+fV845Dg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=C8zqBiAF+/8ByrtHscexhIqNJ3ZB6Q9VGNwYaOueNcmaK2iVDBJ7DZpIMyN51lRoa /kdDa3fYvlvArsXTmjlHyuNAjtVH4DKC+Oco312NYeUL1Iz1dYwnmfI9MKYYGOFCf+ 6fdAPndFlrgVFxJGXwp5I9zXWrfeCx6KfEOihedyO/RE0YoZvI8vFnE09Za7bZxbJQ 5kuCtIORrLGHG2vE4xsI58xJjXeJjCvuKtQyzTekCAL178KuTOc97FuEFAKt8SRvlM 1riAzWuQamXvHnghUF59KN2iD1n7MWJtZ/mPAM7jy2uMfj8GIHqqrCJ5AFZQQeHXLj gDIpHLkooESXg== Date: Tue, 3 Aug 2021 22:07:37 +0300 From: Mike Rapoport To: Catalin Marinas 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: References: <20210803064218.6611-1-rppt@kernel.org> <20210803180526.GD5786@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210803180526.GD5786@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210803_120820_002848_BB4BBA0E X-CRM114-Status: GOOD ( 26.32 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Aug 03, 2021 at 07:05:26PM +0100, Catalin Marinas wrote: > 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). It is already documented: Documentation/admin-guide/kdump/kdump.rst: On arm64, use "crashkernel=Y[@X]". Note that the start address of the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > 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. The doc lies :) memblock_phys_alloc_range() boils down to for_each_free_mem_range_reverse(i, nid, flags, &this_start, &this_end, NULL) { /* clamp this_{start,end} to the user defined limits */ cand = round_down(this_end - size, align); if (cand >= this_start) return cand; } -- Sincerely yours, Mike. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel