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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 8AD59C433E2 for ; Fri, 3 Jul 2020 04:47:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 580F720771 for ; Fri, 3 Jul 2020 04:47:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="WZEhBaa5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726150AbgGCEq7 (ORCPT ); Fri, 3 Jul 2020 00:46:59 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:32515 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725891AbgGCEq7 (ORCPT ); Fri, 3 Jul 2020 00:46:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1593751617; 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=KcSzgsJYu9sLP23m3DckKrOdBZkrV3N6NwnGG2HbKLQ=; b=WZEhBaa5m3GMF1KSURlTs7xygP4AEAMXi6S+yd5EknfcbJqusHH+QMDotaJU+ddwvngiu/ yhtas3KUxguoZkG8gR8Lri+EqgBUglexwKn190cHDAFq9rDDLtKp5QKE98r25264MdSl9Z ECTX47by/8V85DjzjSY84p4wTK9VH2Y= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-370-AXKcsR8RMH2XUyJBsTRA0A-1; Fri, 03 Jul 2020 00:46:52 -0400 X-MC-Unique: AXKcsR8RMH2XUyJBsTRA0A-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D905DBFD1; Fri, 3 Jul 2020 04:46:49 +0000 (UTC) Received: from dhcp-128-65.nay.redhat.com (ovpn-13-10.pek2.redhat.com [10.72.13.10]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2C64173FFF; Fri, 3 Jul 2020 04:46:38 +0000 (UTC) Date: Fri, 3 Jul 2020 12:46:35 +0800 From: Dave Young To: Chen Zhou Cc: tglx@linutronix.de, mingo@redhat.com, bhe@redhat.com, catalin.marinas@arm.com, will@kernel.org, james.morse@arm.com, robh+dt@kernel.org, arnd@arndb.de, John.P.donnelly@oracle.com, prabhakar.pkin@gmail.com, nsaenzjulienne@suse.de, corbet@lwn.net, bhsharma@redhat.com, horms@verge.net.au, guohanjun@huawei.com, xiexiuqi@huawei.com, huawei.libin@huawei.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kexec@lists.infradead.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v10 5/5] kdump: update Documentation about crashkernel on arm64 Message-ID: <20200703044635.GA28640@dhcp-128-65.nay.redhat.com> References: <20200703035816.31289-1-chenzhou10@huawei.com> <20200703035816.31289-6-chenzhou10@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200703035816.31289-6-chenzhou10@huawei.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Thanks for the update, but still some nitpicks :( I'm sorry I did not catch them previously, but maybe it is not worth to repost the whole series if no other changes needed. On 07/03/20 at 11:58am, Chen Zhou wrote: > Now we support crashkernel=X,[low] on arm64, update the Documentation. > We could use parameters "crashkernel=X crashkernel=Y,low" to reserve > memory above 4G. > > Signed-off-by: Chen Zhou > Tested-by: John Donnelly > Tested-by: Prabhakar Kushwaha > --- > Documentation/admin-guide/kdump/kdump.rst | 14 ++++++++++++-- > Documentation/admin-guide/kernel-parameters.txt | 17 +++++++++++++++-- > 2 files changed, 27 insertions(+), 4 deletions(-) > > diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst > index 2da65fef2a1c..e80fc9e28a9a 100644 > --- a/Documentation/admin-guide/kdump/kdump.rst > +++ b/Documentation/admin-guide/kdump/kdump.rst > @@ -299,7 +299,15 @@ Boot into System Kernel > "crashkernel=64M@16M" tells the system kernel to reserve 64 MB of memory > starting at physical address 0x01000000 (16MB) for the dump-capture kernel. > > - On x86 and x86_64, use "crashkernel=64M@16M". > + On x86 use "crashkernel=64M@16M". > + > + On x86_64, use "crashkernel=Y" to select a region under 4G first, and > + fall back to reserve region above 4G. > + We can also use "crashkernel=X,high" to select a region above 4G, which > + also tries to allocate at least 256M below 4G automatically and > + "crashkernel=Y,low" can be used to allocate specified size low memory. > + Use "crashkernel=Y@X" if we really have to reserve memory from specified s/we/you > + start address X. > > On ppc64, use "crashkernel=128M@32M". > > @@ -316,8 +324,10 @@ Boot into System Kernel > kernel will automatically locate the crash kernel image within the > first 512MB of RAM if X is not given. > > - On arm64, use "crashkernel=Y[@X]". Note that the start address of > + On arm64, use "crashkernel=Y[@X]". Note that the start address of > the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > + If crashkernel=Z,low is specified simultaneously, reserve spcified size s/spcified/specified > + low memory firstly and then reserve memory above 4G. > > Load the Dump-capture Kernel > ============================ > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index fb95fad81c79..58a731eed011 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -722,6 +722,9 @@ > [KNL, x86_64] select a region under 4G first, and > fall back to reserve region above 4G when '@offset' > hasn't been specified. > + [KNL, arm64] If crashkernel=X,low is specified, reserve > + spcified size low memory firstly, and then reserve memory s/spcified/specified > + above 4G. > See Documentation/admin-guide/kdump/kdump.rst for further details. > > crashkernel=range1:size1[,range2:size2,...][@offset] > @@ -746,13 +749,23 @@ > requires at least 64M+32K low memory, also enough extra > low memory is needed to make sure DMA buffers for 32-bit > devices won't run out. Kernel would try to allocate at > - at least 256M below 4G automatically. > + least 256M below 4G automatically. > This one let user to specify own low range under 4G > for second kernel instead. > 0: to disable low allocation. > It will be ignored when crashkernel=X,high is not used > or memory reserved is below 4G. > - > + [KNL, arm64] range under 4G. > + This one let user to specify own low range under 4G s/own low/a low > + for crash dump kernel instead. > + Be different from x86_64, kernel reserves specified size > + physical memory region only when this parameter is specified > + instead of trying to reserve at least 256M below 4G > + automatically. > + Use this parameter along with crashkernel=X when we want > + to reserve crashkernel above 4G. If there are devices > + need to use ZONE_DMA in crash dump kernel, it is also > + a good choice. > cryptomgr.notests > [KNL] Disable crypto self-tests > > -- > 2.20.1 > 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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 04C48C433DF for ; Fri, 3 Jul 2020 04:48:13 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 C1EEE20760 for ; 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bh=KcSzgsJYu9sLP23m3DckKrOdBZkrV3N6NwnGG2HbKLQ=; b=RMrHZBfmzhaPZ/gE/12X8x6K59HXnz2/wv4zeG6Y5h+8BRTVSECKKMVarMRLSRCR+TrW29 9J4hxkWpdqsrayc9U77bizCs9OewjOMtPY4p6yQUoD0aY0XN5Pz2TkYJiOa+CSpasprrG4 ZPA1Sez0exjNNW/WBvkmRShSotUfRXE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-370-AXKcsR8RMH2XUyJBsTRA0A-1; Fri, 03 Jul 2020 00:46:52 -0400 X-MC-Unique: AXKcsR8RMH2XUyJBsTRA0A-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D905DBFD1; Fri, 3 Jul 2020 04:46:49 +0000 (UTC) Received: from dhcp-128-65.nay.redhat.com (ovpn-13-10.pek2.redhat.com [10.72.13.10]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2C64173FFF; Fri, 3 Jul 2020 04:46:38 +0000 (UTC) Date: Fri, 3 Jul 2020 12:46:35 +0800 From: Dave Young To: Chen Zhou Subject: Re: [PATCH v10 5/5] kdump: update Documentation about crashkernel on arm64 Message-ID: <20200703044635.GA28640@dhcp-128-65.nay.redhat.com> References: <20200703035816.31289-1-chenzhou10@huawei.com> <20200703035816.31289-6-chenzhou10@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200703035816.31289-6-chenzhou10@huawei.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200703_004656_152870_DF8EF522 X-CRM114-Status: GOOD ( 28.13 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: horms@verge.net.au, John.P.donnelly@oracle.com, xiexiuqi@huawei.com, arnd@arndb.de, bhe@redhat.com, corbet@lwn.net, catalin.marinas@arm.com, bhsharma@redhat.com, guohanjun@huawei.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, linux-doc@vger.kernel.org, mingo@redhat.com, james.morse@arm.com, linux-arm-kernel@lists.infradead.org, huawei.libin@huawei.com, prabhakar.pkin@gmail.com, tglx@linutronix.de, will@kernel.org, nsaenzjulienne@suse.de 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 Hi, Thanks for the update, but still some nitpicks :( I'm sorry I did not catch them previously, but maybe it is not worth to repost the whole series if no other changes needed. On 07/03/20 at 11:58am, Chen Zhou wrote: > Now we support crashkernel=X,[low] on arm64, update the Documentation. > We could use parameters "crashkernel=X crashkernel=Y,low" to reserve > memory above 4G. > > Signed-off-by: Chen Zhou > Tested-by: John Donnelly > Tested-by: Prabhakar Kushwaha > --- > Documentation/admin-guide/kdump/kdump.rst | 14 ++++++++++++-- > Documentation/admin-guide/kernel-parameters.txt | 17 +++++++++++++++-- > 2 files changed, 27 insertions(+), 4 deletions(-) > > diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst > index 2da65fef2a1c..e80fc9e28a9a 100644 > --- a/Documentation/admin-guide/kdump/kdump.rst > +++ b/Documentation/admin-guide/kdump/kdump.rst > @@ -299,7 +299,15 @@ Boot into System Kernel > "crashkernel=64M@16M" tells the system kernel to reserve 64 MB of memory > starting at physical address 0x01000000 (16MB) for the dump-capture kernel. > > - On x86 and x86_64, use "crashkernel=64M@16M". > + On x86 use "crashkernel=64M@16M". > + > + On x86_64, use "crashkernel=Y" to select a region under 4G first, and > + fall back to reserve region above 4G. > + We can also use "crashkernel=X,high" to select a region above 4G, which > + also tries to allocate at least 256M below 4G automatically and > + "crashkernel=Y,low" can be used to allocate specified size low memory. > + Use "crashkernel=Y@X" if we really have to reserve memory from specified s/we/you > + start address X. > > On ppc64, use "crashkernel=128M@32M". > > @@ -316,8 +324,10 @@ Boot into System Kernel > kernel will automatically locate the crash kernel image within the > first 512MB of RAM if X is not given. > > - On arm64, use "crashkernel=Y[@X]". Note that the start address of > + On arm64, use "crashkernel=Y[@X]". Note that the start address of > the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > + If crashkernel=Z,low is specified simultaneously, reserve spcified size s/spcified/specified > + low memory firstly and then reserve memory above 4G. > > Load the Dump-capture Kernel > ============================ > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index fb95fad81c79..58a731eed011 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -722,6 +722,9 @@ > [KNL, x86_64] select a region under 4G first, and > fall back to reserve region above 4G when '@offset' > hasn't been specified. > + [KNL, arm64] If crashkernel=X,low is specified, reserve > + spcified size low memory firstly, and then reserve memory s/spcified/specified > + above 4G. > See Documentation/admin-guide/kdump/kdump.rst for further details. > > crashkernel=range1:size1[,range2:size2,...][@offset] > @@ -746,13 +749,23 @@ > requires at least 64M+32K low memory, also enough extra > low memory is needed to make sure DMA buffers for 32-bit > devices won't run out. Kernel would try to allocate at > - at least 256M below 4G automatically. > + least 256M below 4G automatically. > This one let user to specify own low range under 4G > for second kernel instead. > 0: to disable low allocation. > It will be ignored when crashkernel=X,high is not used > or memory reserved is below 4G. > - > + [KNL, arm64] range under 4G. > + This one let user to specify own low range under 4G s/own low/a low > + for crash dump kernel instead. > + Be different from x86_64, kernel reserves specified size > + physical memory region only when this parameter is specified > + instead of trying to reserve at least 256M below 4G > + automatically. > + Use this parameter along with crashkernel=X when we want > + to reserve crashkernel above 4G. If there are devices > + need to use ZONE_DMA in crash dump kernel, it is also > + a good choice. > cryptomgr.notests > [KNL] Disable crypto self-tests > > -- > 2.20.1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120] helo=us-smtp-1.mimecast.com) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrDbD-0003ji-UH for kexec@lists.infradead.org; Fri, 03 Jul 2020 04:46:57 +0000 Date: Fri, 3 Jul 2020 12:46:35 +0800 From: Dave Young Subject: Re: [PATCH v10 5/5] kdump: update Documentation about crashkernel on arm64 Message-ID: <20200703044635.GA28640@dhcp-128-65.nay.redhat.com> References: <20200703035816.31289-1-chenzhou10@huawei.com> <20200703035816.31289-6-chenzhou10@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200703035816.31289-6-chenzhou10@huawei.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Chen Zhou Cc: horms@verge.net.au, John.P.donnelly@oracle.com, xiexiuqi@huawei.com, arnd@arndb.de, bhe@redhat.com, corbet@lwn.net, catalin.marinas@arm.com, bhsharma@redhat.com, guohanjun@huawei.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, linux-doc@vger.kernel.org, mingo@redhat.com, james.morse@arm.com, linux-arm-kernel@lists.infradead.org, huawei.libin@huawei.com, prabhakar.pkin@gmail.com, tglx@linutronix.de, will@kernel.org, nsaenzjulienne@suse.de Hi, Thanks for the update, but still some nitpicks :( I'm sorry I did not catch them previously, but maybe it is not worth to repost the whole series if no other changes needed. On 07/03/20 at 11:58am, Chen Zhou wrote: > Now we support crashkernel=X,[low] on arm64, update the Documentation. > We could use parameters "crashkernel=X crashkernel=Y,low" to reserve > memory above 4G. > > Signed-off-by: Chen Zhou > Tested-by: John Donnelly > Tested-by: Prabhakar Kushwaha > --- > Documentation/admin-guide/kdump/kdump.rst | 14 ++++++++++++-- > Documentation/admin-guide/kernel-parameters.txt | 17 +++++++++++++++-- > 2 files changed, 27 insertions(+), 4 deletions(-) > > diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst > index 2da65fef2a1c..e80fc9e28a9a 100644 > --- a/Documentation/admin-guide/kdump/kdump.rst > +++ b/Documentation/admin-guide/kdump/kdump.rst > @@ -299,7 +299,15 @@ Boot into System Kernel > "crashkernel=64M@16M" tells the system kernel to reserve 64 MB of memory > starting at physical address 0x01000000 (16MB) for the dump-capture kernel. > > - On x86 and x86_64, use "crashkernel=64M@16M". > + On x86 use "crashkernel=64M@16M". > + > + On x86_64, use "crashkernel=Y" to select a region under 4G first, and > + fall back to reserve region above 4G. > + We can also use "crashkernel=X,high" to select a region above 4G, which > + also tries to allocate at least 256M below 4G automatically and > + "crashkernel=Y,low" can be used to allocate specified size low memory. > + Use "crashkernel=Y@X" if we really have to reserve memory from specified s/we/you > + start address X. > > On ppc64, use "crashkernel=128M@32M". > > @@ -316,8 +324,10 @@ Boot into System Kernel > kernel will automatically locate the crash kernel image within the > first 512MB of RAM if X is not given. > > - On arm64, use "crashkernel=Y[@X]". Note that the start address of > + On arm64, use "crashkernel=Y[@X]". Note that the start address of > the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > + If crashkernel=Z,low is specified simultaneously, reserve spcified size s/spcified/specified > + low memory firstly and then reserve memory above 4G. > > Load the Dump-capture Kernel > ============================ > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index fb95fad81c79..58a731eed011 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -722,6 +722,9 @@ > [KNL, x86_64] select a region under 4G first, and > fall back to reserve region above 4G when '@offset' > hasn't been specified. > + [KNL, arm64] If crashkernel=X,low is specified, reserve > + spcified size low memory firstly, and then reserve memory s/spcified/specified > + above 4G. > See Documentation/admin-guide/kdump/kdump.rst for further details. > > crashkernel=range1:size1[,range2:size2,...][@offset] > @@ -746,13 +749,23 @@ > requires at least 64M+32K low memory, also enough extra > low memory is needed to make sure DMA buffers for 32-bit > devices won't run out. Kernel would try to allocate at > - at least 256M below 4G automatically. > + least 256M below 4G automatically. > This one let user to specify own low range under 4G > for second kernel instead. > 0: to disable low allocation. > It will be ignored when crashkernel=X,high is not used > or memory reserved is below 4G. > - > + [KNL, arm64] range under 4G. > + This one let user to specify own low range under 4G s/own low/a low > + for crash dump kernel instead. > + Be different from x86_64, kernel reserves specified size > + physical memory region only when this parameter is specified > + instead of trying to reserve at least 256M below 4G > + automatically. > + Use this parameter along with crashkernel=X when we want > + to reserve crashkernel above 4G. If there are devices > + need to use ZONE_DMA in crash dump kernel, it is also > + a good choice. > cryptomgr.notests > [KNL] Disable crypto self-tests > > -- > 2.20.1 > _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec