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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 6B84BC433EF for ; Thu, 17 Mar 2022 03:48:51 +0000 (UTC) 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=FniBl/BYO0qXD+PLRb7eDSMi89HT8/VI7k8YCN8nav0=; b=EZpUBd9WRY0KaD kXFXv/AIt9tBa42QWqnSgB9HYWYvN9/nTdYetPC7smhkwghgYTUb5tPraA1aVyD0k2ZqhZOHQFLhB SAAoZGaj/lQam3PAxQnLLv0xbEDN6fYBDMO5qRBa20NTowIyn/ut0efsmE8evFkGDpCDC1HKSTYEk bX+UOeyF0NVUxroLPoOY0tSshuXn+PaG2tajbca9szt8NDMP+ssyOgydCA8kHmlqSf+bcim14iaVl ktdxocW2zG0As8KNsh1XN7cyUE5ye37lnAluz4GN9A9Ov+CbFrOVO79NioY+fgRGxE5Je3Kxcw7nZ LSdKdN83kYnLbzyqgszg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nUh72-00EqNE-Hh; Thu, 17 Mar 2022 03:47:44 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nUh6y-00EqLo-W4 for linux-arm-kernel@lists.infradead.org; Thu, 17 Mar 2022 03:47:42 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1647488860; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=sFQFpL3PGKwla/2hgDhEwqT8DB92GbCW96PCZBbK68s=; b=HrJdJubH8DZciFsP4/AAqGHvsiqbPFyY8imq/+32gmSccb5f0u3by9F1Za0zArCW53jXBU hZ9OWtZTl90mhpPVVB0Xy6ZPdYy4kK6E6KMm5H8gP+WDSFbwjPcOWSigMleN62RRotU9bU BPz9CB5Ke4unHZz3WhhcUShJ7FYHAcc= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-151-BIsiiIozPOuhklban8P0Kg-1; Wed, 16 Mar 2022 23:47:37 -0400 X-MC-Unique: BIsiiIozPOuhklban8P0Kg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id F134C802C16; Thu, 17 Mar 2022 03:47:35 +0000 (UTC) Received: from localhost (ovpn-13-190.pek2.redhat.com [10.72.13.190]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F046E1427B21; Thu, 17 Mar 2022 03:47:34 +0000 (UTC) Date: Thu, 17 Mar 2022 11:47:31 +0800 From: Baoquan He To: "Leizhen (ThunderTown)" Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , linux-kernel@vger.kernel.org, Dave Young , Vivek Goyal , Eric Biederman , kexec@lists.infradead.org, Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, Rob Herring , Frank Rowand , devicetree@vger.kernel.org, Jonathan Corbet , linux-doc@vger.kernel.org, Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou , John Donnelly , Dave Kleikamp Subject: Re: [PATCH v21 3/5] arm64: kdump: reimplement crashkernel=X Message-ID: References: <20220227030717.1464-1-thunder.leizhen@huawei.com> <20220227030717.1464-4-thunder.leizhen@huawei.com> <7d7a3e70-6a46-b722-ef48-7206a47185dd@huawei.com> <05a96786-cfe8-029f-f29a-60fb94129f91@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <05a96786-cfe8-029f-f29a-60fb94129f91@huawei.com> X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220316_204741_192024_FCB272B3 X-CRM114-Status: GOOD ( 35.15 ) 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 03/17/22 at 11:19am, Leizhen (ThunderTown) wrote: > > > On 2022/3/17 10:36, Baoquan He wrote: > > On 03/16/22 at 09:11pm, Leizhen (ThunderTown) wrote: > >> > >> > >> On 2022/3/16 20:11, Baoquan He wrote: > >>> On 02/27/22 at 11:07am, Zhen Lei wrote: > > ...... > > > >>> Hi leizhen, > >>> > >>> I made change on reserve_crashkenrel(), inline comment may be slow. > >>> Please check and consider if they can be taken. > >> > >> That's great. Thank you very much. > >> > >>> > >>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > >>> index 30ae6638ff54..f96351da1e3e 100644 > >>> --- a/arch/arm64/mm/init.c > >>> +++ b/arch/arm64/mm/init.c > >>> @@ -109,38 +109,43 @@ static int __init reserve_crashkernel_low(unsigned long long low_size) > >>> * This function reserves memory area given in "crashkernel=" kernel command > >>> * line parameter. The memory reserved is used by dump capture kernel when > >>> * primary kernel is crashing. > >>> + * > >>> + * NOTE: Reservation of crashkernel,low is special since its existence > >>> + * is not independent, need rely on the existence of crashkernel,high. > >>> + * Hence there are different cases for crashkernel,low reservation: > > > > Considering to update the 3rd line as below: > > > > * NOTE: Reservation of crashkernel,low is special since its existence > > * is not independent, need rely on the existence of crashkernel,high. > > * Here, four cases of crashkernel,low reservation are summarized: > > OK. How about change "crashkernel,low" to "crashkernel low memory"? > "crashkernel=Y,low", "crashkernel=,low" and "crashkernel,low" are very similar, > may dazzle the reader. Fine by me. 'crashkernel low memory' is formal, just make sentence a little longer. Please take what you think fitter. > > > > >>> + * 1) crashkernel=Y,low is specified explicitly, crashkernel,low takes Y; > >>> + * 2) crashkernel=,low is not given, while crashkernel=,high is specified, > >>> + * take the default crashkernel,low value; > >>> + * 3) crashkernel=X is specified, while fallback to get a memory region > >>> + * in high memory, take the default crashkernel,low value; > >>> + * 4) crashkernel='invalid value',low is specified, failed the whole > >>> + * crashkernel reservation and bail out. > >>> */ > >>> static void __init reserve_crashkernel(void) > >>> { > >>> unsigned long long crash_base, crash_size; > >>> unsigned long long crash_low_size; > >>> unsigned long long crash_max = CRASH_ADDR_LOW_MAX; > >>> - int ret; > >>> bool fixed_base, high = false; > >>> char *cmdline = boot_command_line; > >>> + int ret; > >>> > >>> /* crashkernel=X[@offset] */ > >>> ret = parse_crashkernel(cmdline, memblock_phys_mem_size(), > >>> &crash_size, &crash_base); > >>> if (ret || !crash_size) { > >>> - /* crashkernel=X,high */ > >>> ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base); > >>> if (ret || !crash_size) > >>> return; > >>> > >>> - /* crashkernel=Y,low */ > >>> ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base); > >>> if (ret == -ENOENT) > >>> - /* > >>> - * crashkernel=Y,low is not specified explicitly, use > >>> - * default size automatically. > >>> - */ > >>> + /* case #2 of crashkernel,low reservation */ > >>> crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; > >>> else if (ret) > >>> - /* crashkernel=Y,low is specified but Y is invalid */ > >>> + /* case #4 of crashkernel,low reservation */ > >>> return; > >>> > >>> - /* Mark crashkernel=X,high is specified */ > >>> high = true; > >>> crash_max = CRASH_ADDR_HIGH_MAX; > >>> } > >>> @@ -148,7 +153,6 @@ static void __init reserve_crashkernel(void) > >>> fixed_base = !!crash_base; > >>> crash_size = PAGE_ALIGN(crash_size); > >>> > >>> - /* User specifies base address explicitly. */ > >>> if (fixed_base) > >>> crash_max = crash_base + crash_size; > >>> > >>> @@ -172,11 +176,7 @@ static void __init reserve_crashkernel(void) > >>> } > >>> > >>> if (crash_base >= SZ_4G) { > >>> - /* > >>> - * For case crashkernel=X, low memory is not enough and fall > >>> - * back to reserve specified size of memory above 4G, try to > >>> - * allocate minimum required memory below 4G again. > >>> - */ > >>> + /* case #3 of crashkernel,low reservation */ > >>> if (!high) > >>> crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; > >>> > >>> > >>>> > >>>> - /* Current arm64 boot protocol requires 2MB alignment */ > >>>> - crash_base = memblock_phys_alloc_range(crash_size, SZ_2M, > >>>> +retry: > >>>> + crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, > >>>> crash_base, crash_max); > >>>> if (!crash_base) { > >>>> + /* > >>>> + * Attempt to fully allocate low memory failed, fall back > >>>> + * to high memory, the minimum required low memory will be > >>>> + * reserved later. > >>>> + */ > >>>> + if (!fixed_base && (crash_max == CRASH_ADDR_LOW_MAX)) { > >>>> + crash_max = CRASH_ADDR_HIGH_MAX; > >>>> + goto retry; > >>>> + } > >>>> + > >>>> pr_warn("cannot allocate crashkernel (size:0x%llx)\n", > >>>> crash_size); > >>>> return; > >>>> } > >>>> > >>>> + if (crash_base >= SZ_4G) { > >>>> + /* > >>>> + * For case crashkernel=X, low memory is not enough and fall > >>>> + * back to reserve specified size of memory above 4G, try to > >>>> + * allocate minimum required memory below 4G again. > >>>> + */ > >>>> + if (!high) > >>>> + crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; > >>>> + > >>>> + if (reserve_crashkernel_low(crash_low_size)) { > >>>> + memblock_phys_free(crash_base, crash_size); > >>>> + return; > >>>> + } > >>>> + } > >>>> + > >>>> pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", > >>>> crash_base, crash_base + crash_size, crash_size >> 20); > >>>> > >>>> @@ -107,6 +194,9 @@ static void __init reserve_crashkernel(void) > >>>> * map. Inform kmemleak so that it won't try to access it. > >>>> */ > >>>> kmemleak_ignore_phys(crash_base); > >>>> + if (crashk_low_res.end) > >>>> + kmemleak_ignore_phys(crashk_low_res.start); > >>>> + > >>>> crashk_res.start = crash_base; > >>>> crashk_res.end = crash_base + crash_size - 1; > >>>> insert_resource(&iomem_resource, &crashk_res); > >>>> -- > >>>> 2.25.1 > >>>> > >>> > >>> . > >>> > >> > >> -- > >> Regards, > >> Zhen Lei > >> > > > > . > > > > -- > Regards, > Zhen Lei > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel