Re: Mirage Xenstore Stub Domain

[Anil Madhavapeddy <anil@xxxxxxxxxx>]

It would certainly be nicer to arrange for the Xenstore stub domain to have 
access to an emergency console ring in this case.  Is there a Xenconsoled stub 
domain too, Dave, or would this have to be the hypervisor console ring?

-anil

On 15 Jul 2013, at 22:59, James Bielman <jamesjb@xxxxxxxxx> wrote:

> I've hit another snag with the Xenstore stub domain.  I've built 
> "ocaml-xenstore-xen" with Mirari, and I'm launching it early in the dom0 boot 
> process with "init-xenstore-domain".  The xenstore kernel seems to hang with 
> 100% CPU usage trying to write to the console (which makes some sense to me, 
> since nothing is reading from the ring buffer yet).  My guess is that the 
> loop in "OS.Console.write_all" is the culprit---if I stub this function out 
> to return zero, it starts up and works just fine.
> 
> I've been trying to figure out if this is a bootstrapping issue that's 
> somewhat unavoidable or a bug, but I don't yet have enough of a handle on how 
> LWT works to be sure.
> 
> James
> 
> 
> 
> On Mon, Jul 8, 2013 at 4:25 PM, James Bielman <jamesjb@xxxxxxxxx> wrote:
> Thanks! It builds for me now after following your process and hacking up a 
> quick and dirty mirari config file.
> 
> Cheers,
> James
> 
> 
> On Mon, Jul 8, 2013 at 3:10 PM, David Scott <scott.dj@xxxxxxxxx> wrote:
> Hi James,
> 
> I think you're right -- some key interfaces have changed. Since some of the 
> changes are fairly fresh in my memory, I did a first pass at fixing the code.
> 
> The blog post is a bit out of date now. The best way to start is to:
> 
> opam init
> opam switch 4.00.1
> opam remote add xapi-project git://github.com/xapi-project/opam-repo-dev
> opam remote add mirage git://github.com/mirage/opam-repo-dev
> opam install mirage-xen xenstore
> 
> and then clone the repo and build in the 'xen' directory. For me the files 
> compile but fail to link. The next thing to do is to investigate using the 
> 'mirari' tool to link a xen kernel, like the other examples in the 
> mirage/mirage-skeleton repo. This is fallout from the recent (very good IMHO) 
> change to avoid using a special 'opam compiler switch' to install mirage 
> kernels. You can now use a regular (unpatched) compiler and link in the 
> 'mirage-xen' package.
> 
> Sorry for the build breakage!
> 
> Cheers
> Dave
> 
> 
> On Mon, Jul 8, 2013 at 10:10 PM, James Bielman <jamesjb@xxxxxxxxx> wrote:
> Hi all,
> 
> I am attempting to build the Mirage Xenstore stub domain by following these 
> instructions on the Mirage blog:
> 
>   http://www.openmirage.org/blog/xenstore-stub-domain
> 
> However, I'm running into some trouble---it looks like the interfaces for 
> shared memory rings and grant tables have changed since the 
> "xs_transport_domain" module was written.  I'm using Mirage as installed from 
> "opam" and the "ocaml-xenstore-xen" module from the Git  repository at:
> 
>    git://github.com/djs55/ocaml-xenstore-xen
> 
> Is there is an updated repository elsewhere that works with the latest 
> Mirage?  If not, I may take a stab at bringing it up to date, and would 
> appreciate any insight available on gotchas I might run into.
> 
> Thanks,
> James
> 
> 
> 
> 
> -- 
> Dave Scott
> 
>