From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pf1-f194.google.com ([209.85.210.194]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hQmH4-0002Tl-B4 for kexec@lists.infradead.org; Wed, 15 May 2019 05:16:19 +0000 Received: by mail-pf1-f194.google.com with SMTP id g9so708904pfo.11 for ; Tue, 14 May 2019 22:16:16 -0700 (PDT) Subject: Re: [PATCH 4/4] kdump: update Documentation about crashkernel on arm64 References: <20190507035058.63992-1-chenzhou10@huawei.com> <20190507035058.63992-5-chenzhou10@huawei.com> From: Bhupesh Sharma Message-ID: Date: Wed, 15 May 2019 10:46:05 +0530 MIME-Version: 1.0 In-Reply-To: <20190507035058.63992-5-chenzhou10@huawei.com> Content-Language: en-US List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Chen Zhou , catalin.marinas@arm.com, will.deacon@arm.com, akpm@linux-foundation.org, ard.biesheuvel@linaro.org, rppt@linux.ibm.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, ebiederm@xmission.com Cc: wangkefeng.wang@huawei.com, takahiro.akashi@linaro.org, "kexec@lists.infradead.org" , linux-kernel@vger.kernel.org, linux-mm@kvack.org, horms@verge.net.au, Bhupesh SHARMA , linux-arm-kernel@lists.infradead.org On 05/07/2019 09:20 AM, Chen Zhou wrote: > Now we support crashkernel=X,[high,low] on arm64, update the > Documentation. > > Signed-off-by: Chen Zhou > --- > Documentation/admin-guide/kernel-parameters.txt | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 268b10a..03a08aa 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -705,7 +705,7 @@ > memory region [offset, offset + size] for that kernel > image. If '@offset' is omitted, then a suitable offset > is selected automatically. > - [KNL, x86_64] select a region under 4G first, and > + [KNL, x86_64, arm64] select a region under 4G first, and > fall back to reserve region above 4G when '@offset' > hasn't been specified. > See Documentation/kdump/kdump.txt for further details. > @@ -718,14 +718,14 @@ > Documentation/kdump/kdump.txt for an example. > > crashkernel=size[KMG],high > - [KNL, x86_64] range could be above 4G. Allow kernel > + [KNL, x86_64, arm64] range could be above 4G. Allow kernel > to allocate physical memory region from top, so could > be above 4G if system have more than 4G ram installed. > Otherwise memory region will be allocated below 4G, if > available. > It will be ignored if crashkernel=X is specified. > crashkernel=size[KMG],low > - [KNL, x86_64] range under 4G. When crashkernel=X,high > + [KNL, x86_64, arm64] range under 4G. When crashkernel=X,high > is passed, kernel could allocate physical memory region > above 4G, that cause second kernel crash on system > that require some amount of low memory, e.g. swiotlb > IMO, it is a good time to update 'Documentation/kdump/kdump.txt' with this patchset itself for both x86_64 and arm64, where we still specify only the old format for 'crashkernel' boot-argument: Section: Boot into System Kernel ======================= On arm64, use "crashkernel=Y[@X]". Note that the start address of the kernel, X if explicitly specified, must be aligned to 2MiB (0x200000). ... We can update this to add the new crashkernel=size[KMG],low or crashkernel=size[KMG],high format as well. Thanks, Bhupesh _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec