Re: kdump with xen-unstable on efi machine

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 27/11/14 09:49, Ian Campbell wrote:
> On Wed, 2014-11-26 at 14:26 +0000, Andrew Cooper wrote:
>> libxc (or some new alternative) should suck it up and gain some notion
>> of a stable API or ABI (like the rest of the world appears to be able to
>> manage), such that it is possible to compile with an older header and
>> use a newer .so at runtime.
> Retrofitting a stable API/ABI to the melting pot which is libxc simply
> isn't going to work in practice.
>
> IMO the most likely to succeed approach would be to split off the bits
> of libxc which 3rd party's can/should/need to rely on into one of more
> libraries, probably by functional area.
>
> So far I'm aware of plans (or at least desires) to do that for:
>
>       * Interfaces used by device-models/qemu.
>       * The bits which are useful inside a guest (i.e. the
>         various /dev/xen/* related helpers).
>
> So it sounds like libxenkexec should be added to that list.
>
> Ian.
>

Agreed.

For a domU, I think we need libxenevt, libxengnt and libxenstore with
stable API and ABIs.  This in turn will permit libvchan to work without
needing libxenctrl.

For dom0, each of the libraries is going to need basic hypercall
functionality.  It might be worth considering making libxenbasic (name
looking for improvement) which is more along the lines of a privcmd
driver, providing do_hypercall() and bounce buffering.  libxenctrl and
others can then avoid reimplementing the wheel many times.

~Andrew