Messages in this thread | | | Date | Tue, 23 Jul 2013 17:22:36 -0700 | From | Matt Wilson <> | Subject | Re: [Xen-devel] is kexec on Xen domU possible? |
| |
On Mon, Jul 22, 2013 at 11:33:15AM -0700, Greg KH wrote: > On Mon, Jul 22, 2013 at 11:24:46AM -0700, H. Peter Anvin wrote: > > On 07/22/2013 10:20 AM, Eric W. Biederman wrote: > > >>> > > >>> Also, in any virtualized environment the hypervisor can do a better job > > >>> for things like kdump, simply because it can provide two things that are > > >>> otherwise hard to do: > > >>> > > >>> 1. a known-good system state; > > >>> 2. a known-clean kdump image. > > >>> > > >>> As such, I do encourage the virtualization people to (also) develop > > >>> hypervisor-*aware* solutions for these kinds of things. > > >> > > >> In general I agree but if you could not change hypervisor > > >> and/or dom0 (e.g. you are using cloud providers which are > > >> stick to old versions of Xen) then you have no choice. > > > > > > Which tends to be where kexec on panic comes in most cases. Getting > > > platform vendors to do something sane tends to be a multi-year political > > > effort of dubious worth while just solving the problem locally actually > > > gets the problem solved for those who care. > > > > > > > It should not be a "one or the other" issue. > > I don't care about kdump, I care about kexec on domU for people who are > running on cloud providers with old versions of Xen so that they can > control what kernel they can boot, when they want to boot it. If kdump > works as well, that's just a bonus, but it's down on the list of things > for me to be concerned about.
Many Xen-based cloud providers provide a mechanism for users to boot the kernels they want. For example you can use PV-GRUB on EC2 instances to boot a kernel that is stored within an AMI.
For more info: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/UserProvidedkernels.html
--msw
| |