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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT 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 E9E6FC10F0C for ; Thu, 4 Apr 2019 14:46:55 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 96CD02171F for ; Thu, 4 Apr 2019 14:46:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 96CD02171F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2862F6B0007; Thu, 4 Apr 2019 10:46:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 20D2B6B0008; Thu, 4 Apr 2019 10:46:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 087D06B000A; Thu, 4 Apr 2019 10:46:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by kanga.kvack.org (Postfix) with ESMTP id A7E326B0007 for ; Thu, 4 Apr 2019 10:46:54 -0400 (EDT) Received: by mail-ed1-f70.google.com with SMTP id j3so1566190edb.14 for ; Thu, 04 Apr 2019 07:46:54 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:date:from:to :cc:subject:references:mime-version:content-disposition:in-reply-to :user-agent:message-id; bh=by+qc73PFufYAJcEzQJv2SX/8Vxa3BKPss43cTpMvFU=; b=rsxGgGpsYP1iquj/MBc1dt24zWtX1IlfCTikxgKRrMVyX+/NdjV7vu75IPrhHP/AaR I0fgzY+ShD8TJMzUL9XRX/Jdk5wn0+I6WTgwWN9nrfO2nMd6dOzVb680FMRleODK041e NaC9d+aOboqvzSsZwRlI+hJKEjhFD48b1rcEMCT8m/ZOXMFnmLQbH7GG85fG1BoeFqXi y5DiU86HYwpvhQYyhkObVRRHw0KhYMZFD2RzazX860t2ZJewxv3YHnY9CMvkWqZhBH3L 3pl6ZU0qs8MZMjeO4FtZpo2u67d4/7AaWURWjEvKwRUO5Hz3T/cFTYY56fxZyWoWj3u5 bSVQ== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of rppt@linux.ibm.com designates 148.163.158.5 as permitted sender) smtp.mailfrom=rppt@linux.ibm.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ibm.com X-Gm-Message-State: APjAAAXmKOLC54v8A3naT8U+cewpyb8fp1+Jutrrm/OyzKWdj7nSB+XG Zo1lc7/8PqHF5+L8ANrPUfu6JJkwEygk9Bmf+zi1wBOdvGG2N/IciiwEH+JrrOUgN0GPI6Nl8TJ M5yGKN1jDrrT4VuzWGKysPqO4EdEaSybb0E29+rDln1Mw5xuybLZJdTPbTTMqFFoQRA== X-Received: by 2002:a50:e609:: with SMTP id y9mr4043518edm.81.1554389214232; Thu, 04 Apr 2019 07:46:54 -0700 (PDT) X-Google-Smtp-Source: APXvYqy5Q1KpdP6OCvx1/5FtAsvHU1/zmTZUzysznHbE/z1Jme/k13ntnepilRz+F4kKk+owUHbW X-Received: by 2002:a50:e609:: with SMTP id y9mr4043470edm.81.1554389213390; Thu, 04 Apr 2019 07:46:53 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1554389213; cv=none; d=google.com; s=arc-20160816; b=u6Rm//oO9mu5lwSgPB6IiU0wo/Cj026FR6t4OlCJawJewSqrrHxWMOjSt6I4zsV3GZ RJpGUPHdoqJ/wXAK6hBqBS6kNHGa7Lnfks6sQtBTtbEVWWNH1B9/+0zB6Uoy9O8OQ8Zd GmxSrUkJQePFFQj9h9gqZUHBda26jioduKhuJSjh9yh6OcJaseSrM0XY4LlnoqpzoXAN Emw2HeSVPXqRk1mOAvKupXpuq8y2DRacj5SLCMy+UgGdggtozoLKePpf44Xjd7MnYM6H Xu1FFfBo/9tNSGSsR88023YkkMRuzVuHDZDdLSuQ2RsLMv1t6f6ORYj1bp0gmCyvo4XS D4EQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=message-id:user-agent:in-reply-to:content-disposition:mime-version :references:subject:cc:to:from:date; bh=by+qc73PFufYAJcEzQJv2SX/8Vxa3BKPss43cTpMvFU=; b=Cj3n89XXTHoEE8l5x36z2rJ8ujcZH9dKJ2px/sqoComB4Cx0Iu/IQRdUNktYjw9zGP zbc63dOZPuRbmdcj22aqOsbUc59C1bRVceJTa7qs0FgH4A1L4nZQ7+kXdaOwRKk/OHJM hmlnzS4z4D0d1kLU2FegTHydNeEmsSdQ+iT0sIAdVz2wm6nT68b+rZnB4+5qyGGgUu9j U6CJ+U41nsI9lUICc8250s+Lbdd5TmI4aN+/pti3u5j8lrM2b5jVO9STIkf+bTCQLN57 uqsuJEEv7g0hxcdeqwI3BCE9qs3jOAjlJnSpRO1Yjii20NqqQpu4/6FtrrxlpNOzRkpf rsSw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of rppt@linux.ibm.com designates 148.163.158.5 as permitted sender) smtp.mailfrom=rppt@linux.ibm.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id q2si5552311edn.429.2019.04.04.07.46.52 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 04 Apr 2019 07:46:53 -0700 (PDT) Received-SPF: pass (google.com: domain of rppt@linux.ibm.com designates 148.163.158.5 as permitted sender) client-ip=148.163.158.5; Authentication-Results: mx.google.com; spf=pass (google.com: domain of rppt@linux.ibm.com designates 148.163.158.5 as permitted sender) smtp.mailfrom=rppt@linux.ibm.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ibm.com Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x34EjH7e106967 for ; Thu, 4 Apr 2019 10:46:52 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0b-001b2d01.pphosted.com with ESMTP id 2rnjrevk9n-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 04 Apr 2019 10:46:47 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 4 Apr 2019 15:46:28 +0100 Received: from b06cxnps3075.portsmouth.uk.ibm.com (9.149.109.195) by e06smtp03.uk.ibm.com (192.168.101.133) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 4 Apr 2019 15:46:24 +0100 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x34EkNON60031206 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 4 Apr 2019 14:46:23 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2BDEAA405B; Thu, 4 Apr 2019 14:46:23 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B260BA4060; Thu, 4 Apr 2019 14:46:21 +0000 (GMT) Received: from rapoport-lnx (unknown [9.148.205.215]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Thu, 4 Apr 2019 14:46:21 +0000 (GMT) Date: Thu, 4 Apr 2019 17:46:19 +0300 From: Mike Rapoport To: Chen Zhou Cc: catalin.marinas@arm.com, will.deacon@arm.com, akpm@linux-foundation.org, ard.biesheuvel@linaro.org, takahiro.akashi@linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, linux-mm@kvack.org, wangkefeng.wang@huawei.com Subject: Re: [PATCH 1/3] arm64: kdump: support reserving crashkernel above 4G References: <20190403030546.23718-1-chenzhou10@huawei.com> <20190403030546.23718-2-chenzhou10@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190403030546.23718-2-chenzhou10@huawei.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-TM-AS-GCONF: 00 x-cbid: 19040414-0012-0000-0000-0000030B47C8 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19040414-0013-0000-0000-000021435741 Message-Id: <20190404144618.GB6433@rapoport-lnx> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-04-04_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1904040095 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: Hi, On Wed, Apr 03, 2019 at 11:05:44AM +0800, Chen Zhou wrote: > When crashkernel is reserved above 4G in memory, kernel should > reserve some amount of low memory for swiotlb and some DMA buffers. > > Kernel would try to allocate at least 256M below 4G automatically > as x86_64 if crashkernel is above 4G. Meanwhile, support > crashkernel=X,[high,low] in arm64. > > Signed-off-by: Chen Zhou > --- > arch/arm64/kernel/setup.c | 3 ++ > arch/arm64/mm/init.c | 71 +++++++++++++++++++++++++++++++++++++++++++++-- > 2 files changed, 71 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c > index 413d566..82cd9a0 100644 > --- a/arch/arm64/kernel/setup.c > +++ b/arch/arm64/kernel/setup.c > @@ -243,6 +243,9 @@ static void __init request_standard_resources(void) > request_resource(res, &kernel_data); > #ifdef CONFIG_KEXEC_CORE > /* Userspace will find "Crash kernel" region in /proc/iomem. */ > + if (crashk_low_res.end && crashk_low_res.start >= res->start && > + crashk_low_res.end <= res->end) > + request_resource(res, &crashk_low_res); > if (crashk_res.end && crashk_res.start >= res->start && > crashk_res.end <= res->end) > request_resource(res, &crashk_res); > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index 6bc1350..ceb2a25 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -64,6 +64,57 @@ EXPORT_SYMBOL(memstart_addr); > phys_addr_t arm64_dma_phys_limit __ro_after_init; > > #ifdef CONFIG_KEXEC_CORE > +static int __init reserve_crashkernel_low(void) > +{ > + unsigned long long base, low_base = 0, low_size = 0; > + unsigned long total_low_mem; > + int ret; > + > + total_low_mem = memblock_mem_size(1UL << (32 - PAGE_SHIFT)); > + > + /* crashkernel=Y,low */ > + ret = parse_crashkernel_low(boot_command_line, total_low_mem, &low_size, &base); > + if (ret) { > + /* > + * two parts from lib/swiotlb.c: > + * -swiotlb size: user-specified with swiotlb= or default. > + * > + * -swiotlb overflow buffer: now hardcoded to 32k. We round it > + * to 8M for other buffers that may need to stay low too. Also > + * make sure we allocate enough extra low memory so that we > + * don't run out of DMA buffers for 32-bit devices. > + */ > + low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20); > + } else { > + /* passed with crashkernel=0,low ? */ > + if (!low_size) > + return 0; > + } > + > + low_base = memblock_find_in_range(0, 1ULL << 32, low_size, SZ_2M); > + if (!low_base) { > + pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", > + (unsigned long)(low_size >> 20)); > + return -ENOMEM; > + } > + > + ret = memblock_reserve(low_base, low_size); > + if (ret) { > + pr_err("%s: Error reserving crashkernel low memblock.\n", __func__); > + return ret; > + } > + > + pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System RAM: %ldMB)\n", > + (unsigned long)(low_size >> 20), > + (unsigned long)(low_base >> 20), > + (unsigned long)(total_low_mem >> 20)); > + > + crashk_low_res.start = low_base; > + crashk_low_res.end = low_base + low_size - 1; > + > + return 0; > +} > + > /* > * reserve_crashkernel() - reserves memory for crash kernel > * > @@ -74,19 +125,28 @@ phys_addr_t arm64_dma_phys_limit __ro_after_init; > static void __init reserve_crashkernel(void) > { > unsigned long long crash_base, crash_size; > + bool high = false; > int ret; > > ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), > &crash_size, &crash_base); > /* no crashkernel= or invalid value specified */ > - if (ret || !crash_size) > - return; > + if (ret || !crash_size) { > + /* crashkernel=X,high */ > + ret = parse_crashkernel_high(boot_command_line, memblock_phys_mem_size(), > + &crash_size, &crash_base); > + if (ret || !crash_size) > + return; > + high = true; > + } > > crash_size = PAGE_ALIGN(crash_size); > > if (crash_base == 0) { > /* Current arm64 boot protocol requires 2MB alignment */ > - crash_base = memblock_find_in_range(0, ARCH_LOW_ADDRESS_LIMIT, > + crash_base = memblock_find_in_range(0, > + high ? memblock_end_of_DRAM() > + : ARCH_LOW_ADDRESS_LIMIT, > crash_size, SZ_2M); > if (crash_base == 0) { > pr_warn("cannot allocate crashkernel (size:0x%llx)\n", > @@ -112,6 +172,11 @@ static void __init reserve_crashkernel(void) > } > memblock_reserve(crash_base, crash_size); > > + if (crash_base >= SZ_4G && reserve_crashkernel_low()) { > + memblock_free(crash_base, crash_size); > + return; > + } > + This very reminds what x86 does. Any chance some of the code can be reused rather than duplicated? > pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", > crash_base, crash_base + crash_size, crash_size >> 20); > > -- > 2.7.4 > -- Sincerely yours, Mike.