Re: Kexec and libxenctlr.so

[Jürgen Groß <jgross@xxxxxxxx>]

On 11.06.20 16:57, Julien Grall wrote:
> Hi all,
>
> kexec-tools has an option to load dynamically libxenctlr.so (not 
> .so.4.x) (see [1]).
> Given that the library has never been considered stable, it is probably 
> a disaster that is waiting to happen.
> Looking at the tree kexec is using the follow libxc functions:
>     - xc_kexec_get_range()
>     - xc_kexec_load()
>     - xc_kexec_unload()
>     - xc_kexec_status()
>     - xc_kexec_exec()
>     - xc_version()
>     - xc_interface_open()
>     - xc_interface_close()
>     - xc_get_max_cpus()
>     - xc_get_machine_memory_map()
>
> I think it is uncontroversial that we want a new stable library for all 
> the xc_kexec_* functions (maybe libxenexec)?
> However I am not entirely sure where to put the others.
>
> I am thinking to introduce libxensysctl for xc_get_max_cpus() as it is a 
> XEN_SYSCTL. We could possibly include xc_get_machine_memory_map() 
> (despite it is a XENMEM_).
> For xc_version(), I am thinking to extend libxentoolcore to also include 
> "stable xen API".
> Any opinion on the approach?
You could consider hypfs (at least for some of the functionality).

xc_version() and xc_get_max_cpus() would be rather easy.
xc_get_machine_memory_map() is using a stable hypercall used by
the kernel, too.


Juergen