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=-17.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 F0C30C433DB for ; Thu, 18 Feb 2021 10:22:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9A9AA64E68 for ; Thu, 18 Feb 2021 10:22:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230026AbhBRJyq (ORCPT ); Thu, 18 Feb 2021 04:54:46 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:60479 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231169AbhBRImA (ORCPT ); Thu, 18 Feb 2021 03:42:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613637633; 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=2qT1dk1aGHMRzxn21hoyRJNd+7TB5SutKvcXqZ00fOs=; b=L05T/8+X94V1xiBI3RBB5LwVjunXj7b/Uwqoy76Xh3WvsXVifR6Vs1LWizebEFg3Ul5h+u bK0mm7jqOjfJKjR/u680+FX1NCowfyxm7dC+MPJuJa1DqWaQgGcC0BBM/hqISzFRPzQN/o xF634ym2vxwREDytifVGIUbqVnsJSUE= 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-269-Jj7_5E49NM2-6xsTsCFijg-1; Thu, 18 Feb 2021 03:40:16 -0500 X-MC-Unique: Jj7_5E49NM2-6xsTsCFijg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1AD37192AB79; Thu, 18 Feb 2021 08:40:13 +0000 (UTC) Received: from localhost (ovpn-12-112.pek2.redhat.com [10.72.12.112]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B238B19C47; Thu, 18 Feb 2021 08:40:08 +0000 (UTC) Date: Thu, 18 Feb 2021 16:40:06 +0800 From: Baoquan He To: Chen Zhou Cc: mingo@redhat.com, tglx@linutronix.de, rppt@kernel.org, dyoung@redhat.com, catalin.marinas@arm.com, will@kernel.org, nsaenzjulienne@suse.de, corbet@lwn.net, John.P.donnelly@oracle.com, prabhakar.pkin@gmail.com, horms@verge.net.au, robh+dt@kernel.org, arnd@arndb.de, james.morse@arm.com, xiexiuqi@huawei.com, guohanjun@huawei.com, huawei.libin@huawei.com, wangkefeng.wang@huawei.com, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org Subject: Re: [PATCH v14 11/11] kdump: update Documentation about crashkernel Message-ID: <20210218083822.GL2871@MiWiFi-R3L-srv> References: <20210130071025.65258-1-chenzhou10@huawei.com> <20210130071025.65258-12-chenzhou10@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210130071025.65258-12-chenzhou10@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/30/21 at 03:10pm, Chen Zhou wrote: > For arm64, the behavior of crashkernel=X has been changed, which > tries low allocation in DMA zone and fall back to high allocation > if it fails. > > We can also use "crashkernel=X,high" to select a high region above > DMA zone, which also tries to allocate at least 256M low memory in > DMA zone automatically and "crashkernel=Y,low" can be used to allocate > specified size low memory. > > So update the Documentation. Nice document adding which also takes care of x86 code implementation, thanks. By the way, maybe you can remove John's 'Tested-by' since it doesn't make much sense to test a document patch. Acked-by: Baoquan He > > Signed-off-by: Chen Zhou > Tested-by: John Donnelly > --- > Documentation/admin-guide/kdump/kdump.rst | 22 ++++++++++++++++--- > .../admin-guide/kernel-parameters.txt | 11 ++++++++-- > 2 files changed, 28 insertions(+), 5 deletions(-) > > diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst > index 75a9dd98e76e..0877c76f8015 100644 > --- a/Documentation/admin-guide/kdump/kdump.rst > +++ b/Documentation/admin-guide/kdump/kdump.rst > @@ -299,7 +299,16 @@ 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=X" to select a region under 4G first, and > + fall back to reserve region above 4G. And go for high allocation > + directly if the required size is too large. > + 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 you really have to reserve memory from specified > + start address X. > > On ppc64, use "crashkernel=128M@32M". > > @@ -316,8 +325,15 @@ 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 > - the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > + On arm64, use "crashkernel=X" to try low allocation in DMA zone and > + fall back to high allocation if it fails. > + We can also use "crashkernel=X,high" to select a high region above > + DMA zone, which also tries to allocate at least 256M low memory in > + DMA zone automatically. > + "crashkernel=Y,low" can be used to allocate specified size low memory. > + Use "crashkernel=Y@X" if you really have to reserve memory from > + specified start address X. Note that the start address of the kernel, > + X if explicitly specified, must be aligned to 2MiB (0x200000). > > Load the Dump-capture Kernel > ============================ > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index a10b545c2070..908e5c8b61ba 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -738,6 +738,9 @@ > [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] Try low allocation in DMA zone and fall back > + to high allocation if it fails when '@offset' hasn't been > + specified. > See Documentation/admin-guide/kdump/kdump.rst for further details. > > crashkernel=range1:size1[,range2:size2,...][@offset] > @@ -754,6 +757,8 @@ > Otherwise memory region will be allocated below 4G, if > available. > It will be ignored if crashkernel=X is specified. > + [KNL, arm64] range in high memory. > + Allow kernel to allocate physical memory region from top. > crashkernel=size[KMG],low > [KNL, X86-64] range under 4G. When crashkernel=X,high > is passed, kernel could allocate physical memory region > @@ -762,13 +767,15 @@ > 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 in low memory. > + This one let user to specify a low range in DMA zone for > + crash dump kernel. > 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=-15.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 C57EAC433DB for ; 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bh=2qT1dk1aGHMRzxn21hoyRJNd+7TB5SutKvcXqZ00fOs=; b=VC+aiYOoj2YdnCbpjqYDuOGjlAxFlZvvZ4nmwsAQNJXYzsz8qyXsMgB+b8QiX06bEjg/Tg 6dIu01NTz4B54vyluUL0sQ9LpRitMOQmHokgOqP9gh+6vguHie7yrecGFlupSqcHQJRdlJ c5X7JnqsMCNjJ7BKoZKgUFnLsv7FI8k= 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-269-Jj7_5E49NM2-6xsTsCFijg-1; Thu, 18 Feb 2021 03:40:16 -0500 X-MC-Unique: Jj7_5E49NM2-6xsTsCFijg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1AD37192AB79; Thu, 18 Feb 2021 08:40:13 +0000 (UTC) Received: from localhost (ovpn-12-112.pek2.redhat.com [10.72.12.112]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B238B19C47; Thu, 18 Feb 2021 08:40:08 +0000 (UTC) Date: Thu, 18 Feb 2021 16:40:06 +0800 From: Baoquan He To: Chen Zhou Subject: Re: [PATCH v14 11/11] kdump: update Documentation about crashkernel Message-ID: <20210218083822.GL2871@MiWiFi-R3L-srv> References: <20210130071025.65258-1-chenzhou10@huawei.com> <20210130071025.65258-12-chenzhou10@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210130071025.65258-12-chenzhou10@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210218_034021_621031_F39592DD X-CRM114-Status: GOOD ( 31.37 ) 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: wangkefeng.wang@huawei.com, linux-doc@vger.kernel.org, catalin.marinas@arm.com, huawei.libin@huawei.com, guohanjun@huawei.com, will@kernel.org, corbet@lwn.net, mingo@redhat.com, dyoung@redhat.com, John.P.donnelly@oracle.com, arnd@arndb.de, xiexiuqi@huawei.com, horms@verge.net.au, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, james.morse@arm.com, rppt@kernel.org, prabhakar.pkin@gmail.com, 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 On 01/30/21 at 03:10pm, Chen Zhou wrote: > For arm64, the behavior of crashkernel=X has been changed, which > tries low allocation in DMA zone and fall back to high allocation > if it fails. > > We can also use "crashkernel=X,high" to select a high region above > DMA zone, which also tries to allocate at least 256M low memory in > DMA zone automatically and "crashkernel=Y,low" can be used to allocate > specified size low memory. > > So update the Documentation. Nice document adding which also takes care of x86 code implementation, thanks. By the way, maybe you can remove John's 'Tested-by' since it doesn't make much sense to test a document patch. Acked-by: Baoquan He > > Signed-off-by: Chen Zhou > Tested-by: John Donnelly > --- > Documentation/admin-guide/kdump/kdump.rst | 22 ++++++++++++++++--- > .../admin-guide/kernel-parameters.txt | 11 ++++++++-- > 2 files changed, 28 insertions(+), 5 deletions(-) > > diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst > index 75a9dd98e76e..0877c76f8015 100644 > --- a/Documentation/admin-guide/kdump/kdump.rst > +++ b/Documentation/admin-guide/kdump/kdump.rst > @@ -299,7 +299,16 @@ 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=X" to select a region under 4G first, and > + fall back to reserve region above 4G. And go for high allocation > + directly if the required size is too large. > + 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 you really have to reserve memory from specified > + start address X. > > On ppc64, use "crashkernel=128M@32M". > > @@ -316,8 +325,15 @@ 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 > - the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > + On arm64, use "crashkernel=X" to try low allocation in DMA zone and > + fall back to high allocation if it fails. > + We can also use "crashkernel=X,high" to select a high region above > + DMA zone, which also tries to allocate at least 256M low memory in > + DMA zone automatically. > + "crashkernel=Y,low" can be used to allocate specified size low memory. > + Use "crashkernel=Y@X" if you really have to reserve memory from > + specified start address X. Note that the start address of the kernel, > + X if explicitly specified, must be aligned to 2MiB (0x200000). > > Load the Dump-capture Kernel > ============================ > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index a10b545c2070..908e5c8b61ba 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -738,6 +738,9 @@ > [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] Try low allocation in DMA zone and fall back > + to high allocation if it fails when '@offset' hasn't been > + specified. > See Documentation/admin-guide/kdump/kdump.rst for further details. > > crashkernel=range1:size1[,range2:size2,...][@offset] > @@ -754,6 +757,8 @@ > Otherwise memory region will be allocated below 4G, if > available. > It will be ignored if crashkernel=X is specified. > + [KNL, arm64] range in high memory. > + Allow kernel to allocate physical memory region from top. > crashkernel=size[KMG],low > [KNL, X86-64] range under 4G. When crashkernel=X,high > is passed, kernel could allocate physical memory region > @@ -762,13 +767,15 @@ > 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 in low memory. > + This one let user to specify a low range in DMA zone for > + crash dump kernel. > 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-124.mimecast.com ([216.205.24.124]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lCerG-00086O-Pz for kexec@lists.infradead.org; Thu, 18 Feb 2021 08:40:23 +0000 Date: Thu, 18 Feb 2021 16:40:06 +0800 From: Baoquan He Subject: Re: [PATCH v14 11/11] kdump: update Documentation about crashkernel Message-ID: <20210218083822.GL2871@MiWiFi-R3L-srv> References: <20210130071025.65258-1-chenzhou10@huawei.com> <20210130071025.65258-12-chenzhou10@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210130071025.65258-12-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: wangkefeng.wang@huawei.com, linux-doc@vger.kernel.org, catalin.marinas@arm.com, huawei.libin@huawei.com, guohanjun@huawei.com, will@kernel.org, corbet@lwn.net, mingo@redhat.com, dyoung@redhat.com, John.P.donnelly@oracle.com, arnd@arndb.de, xiexiuqi@huawei.com, horms@verge.net.au, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, james.morse@arm.com, rppt@kernel.org, prabhakar.pkin@gmail.com, nsaenzjulienne@suse.de On 01/30/21 at 03:10pm, Chen Zhou wrote: > For arm64, the behavior of crashkernel=X has been changed, which > tries low allocation in DMA zone and fall back to high allocation > if it fails. > > We can also use "crashkernel=X,high" to select a high region above > DMA zone, which also tries to allocate at least 256M low memory in > DMA zone automatically and "crashkernel=Y,low" can be used to allocate > specified size low memory. > > So update the Documentation. Nice document adding which also takes care of x86 code implementation, thanks. By the way, maybe you can remove John's 'Tested-by' since it doesn't make much sense to test a document patch. Acked-by: Baoquan He > > Signed-off-by: Chen Zhou > Tested-by: John Donnelly > --- > Documentation/admin-guide/kdump/kdump.rst | 22 ++++++++++++++++--- > .../admin-guide/kernel-parameters.txt | 11 ++++++++-- > 2 files changed, 28 insertions(+), 5 deletions(-) > > diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admin-guide/kdump/kdump.rst > index 75a9dd98e76e..0877c76f8015 100644 > --- a/Documentation/admin-guide/kdump/kdump.rst > +++ b/Documentation/admin-guide/kdump/kdump.rst > @@ -299,7 +299,16 @@ 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=X" to select a region under 4G first, and > + fall back to reserve region above 4G. And go for high allocation > + directly if the required size is too large. > + 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 you really have to reserve memory from specified > + start address X. > > On ppc64, use "crashkernel=128M@32M". > > @@ -316,8 +325,15 @@ 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 > - the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). > + On arm64, use "crashkernel=X" to try low allocation in DMA zone and > + fall back to high allocation if it fails. > + We can also use "crashkernel=X,high" to select a high region above > + DMA zone, which also tries to allocate at least 256M low memory in > + DMA zone automatically. > + "crashkernel=Y,low" can be used to allocate specified size low memory. > + Use "crashkernel=Y@X" if you really have to reserve memory from > + specified start address X. Note that the start address of the kernel, > + X if explicitly specified, must be aligned to 2MiB (0x200000). > > Load the Dump-capture Kernel > ============================ > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index a10b545c2070..908e5c8b61ba 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -738,6 +738,9 @@ > [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] Try low allocation in DMA zone and fall back > + to high allocation if it fails when '@offset' hasn't been > + specified. > See Documentation/admin-guide/kdump/kdump.rst for further details. > > crashkernel=range1:size1[,range2:size2,...][@offset] > @@ -754,6 +757,8 @@ > Otherwise memory region will be allocated below 4G, if > available. > It will be ignored if crashkernel=X is specified. > + [KNL, arm64] range in high memory. > + Allow kernel to allocate physical memory region from top. > crashkernel=size[KMG],low > [KNL, X86-64] range under 4G. When crashkernel=X,high > is passed, kernel could allocate physical memory region > @@ -762,13 +767,15 @@ > 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 in low memory. > + This one let user to specify a low range in DMA zone for > + crash dump kernel. > cryptomgr.notests > [KNL] Disable crypto self-tests > > -- > 2.20.1 > _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec