From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from kirsty.vergenet.net ([202.4.237.240]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a3eJ8-0005CL-B2 for kexec@lists.infradead.org; Tue, 01 Dec 2015 06:20:59 +0000 Date: Tue, 1 Dec 2015 15:20:32 +0900 From: Simon Horman Subject: Re: [RFC PATCH] crashdump/x86: Add option to get crash kernel region size Message-ID: <20151201062032.GC16260@verge.net.au> References: <1448741644-905-1-git-send-email-daniel.kiper@oracle.com> <20151129235532.GB13342@verge.net.au> <20151130073931.GZ4768@olila.local.net-space.pl> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20151130073931.GZ4768@olila.local.net-space.pl> 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: Daniel Kiper Cc: keir@xen.org, konrad.wilk@oracle.com, andrew.cooper3@citrix.com, kexec@lists.infradead.org, david.vrabel@citrix.com, jbeulich@suse.com, xen-devel@lists.xenproject.org On Mon, Nov 30, 2015 at 08:39:31AM +0100, Daniel Kiper wrote: > On Mon, Nov 30, 2015 at 08:55:32AM +0900, Simon Horman wrote: > > On Sat, Nov 28, 2015 at 09:14:04PM +0100, Daniel Kiper wrote: > > > Crash kernel region size is available via sysfs on Linux running on > > > bare metal. However, this does not work when Linux runs as Xen dom0. > > > In this case Xen crash kernel region size should be established using > > > __HYPERVISOR_kexec_op hypercall (Linux kernel kexec functionality does > > > not make a lot of sense in Xen dom0). Sadly hypercalls are not easily > > > accessible using shell scripts or something like that. Potentially we > > > can check "xl dmesg" output for crashkernel option but this is not nice. > > > So, let's add this functionality, for Linux running on bare metal and > > > as Xen dom0, to kexec-tools. This way kdump scripts may establish crash > > > kernel region size in one way regardless of platform. All burden of > > > platform detection lies on kexec-tools. > > > > > > Figure (and unit) displayed by this new kexec-tools functionality is > > > the same as one taken from /sys/kernel/kexec_crash_size. > > > > > > This functionality is available on x86 platform only. If idea is acceptable > > > then I can prepare patches for other platforms (if it is possible and make > > > sense) and repost them as fully flagged patch series. > > > > > > Signed-off-by: Daniel Kiper > > > > Thanks, applied. > > Thanks a lot. However, this patch itself breaks build on other platforms. > That is why I posted it as a RFC. To fix this I can post similar patches > for other platforms (this will happen probably tomorrow or on Wednesday > but no later than by the end of this week). Or you can revert this patch > and than I repost it as a part of fully functional patch series. Sorry for being a bit too hasty. I will revert. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec