Port-xen archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: reducing XENU kernel config maintenance



On Wed, Mar 01, 2006 at 02:16:34PM +0100, Hubert Feyrer wrote:
> 
> Is there a good reason not to define XENU in terms of the XEN0 kernel 
> config? Comparing the two configs, how about the following? (I understand 
> that this may leave in all the pci drivers... some change for config(8) to 
> do that properly may be needed).

That's config(1), and it already does the right thing in this case.

> The reason to do something like this would be to reduce maintenance costs 
> and avoid errors (and defining XEN0 in terms of a GENERIC kernel would be 
> nice, too, in turn).
> 
> Open questions:
>  * is options WSDISPLAY_SCROLLSUPPORT left out in XENU on purpose, or was
>     XENU just not updated (see "avoid errors")
>  * should wd*, sd*, cd* at hypervisor be enabled?
>  * A comment on what 'xenevt' is would be nice in XEN0
> 
> 
>  - Hubert
>    Department Against Redundancy Department
> 
> 
> #     $NetBSD$
> #
> # XENU kernel, defined in terms of XEN0
> #
> include "arch/i386/conf/XEN0"
> 
> no options    DOM0OPS
> no options    WSDISPLAY_SCROLLSUPPORT         # is that on purpose?
> 
> xennet*       at hypervisor?          # Xen virtual network interface
> 
> no pci*               at hypervisor? bus ?    # Prevent access to PCI bus

I like "no pci" better, but as there is no other root instance for pci,
just removing that instance is fine.

You want "no isa", too.  I don't think you need to remove anything else,
but  a throrough check has to be done.

> xbd*          at hypervisor?          # Xen virtual block device
> #wd*          at hypervisor?          # Xen vbd (wd identity)         # rm?
> #sd*          at hypervisor?          # Xen vbd (sd identity)         # rm?
> #cd*          at hypervisor?          # Xen vbd (cd identity)         # rm?
> 
> no pseudo-device      xenevt

I have no opinion on the matter, but note that maintaining XEN0 and XENU
won't be that much easier:  when adding something to XEN0, one will have
to check whether it's fine for XENU or not.  Your open questions kind of
make that point.

-- 
Quentin Garnier - cube%cubidou.net@localhost - cube%NetBSD.org@localhost
"When I find the controls, I'll go where I like, I'll know where I want
to be, but maybe for now I'll stay right here on a silent sea."
KT Tunstall, Silent Sea, Eye to the Telescope, 2004.

Attachment: pgpipuAjYuXxE.pgp
Description: PGP signature



Home | Main Index | Thread Index | Old Index