No worries Andrew, it was my first patch, thank you for the response.
It's based on Xen 4.8
Dom0 should be controlling it, but I wasn't aware of the Security implications.
The scope isn't well documented:
More experimental as it worked with my Laptop.
Thank you for your time
On 18/04/2019 09:56, Dylanger Daly wrote:
> Giving Laptop Users the ability to Undervolt and change Temp Throttle Limits.
>
> Signed-off-by: Dylanger Daly <dylanger@thegrail.co>
Thankyou for the patch. Which version of Xen is it against? It is
fairly old, given that the function you patch has now moved to
arch/x86/pv/emul-priv-op.c. Furthermore, this is the legacy path, so
the functions this should be added to are guest_{rdmsr,wrmsr}() in
arch/x86/msr.c
What entity is controlling this?
Sadly, there are a number of issues. You open these MSRs up to
unprivileged domUs, and there is a mismatch between the vcpus/pcpus.
What is the scope of these MSRs? I guess dom0 is going to write them on
all cores, but as dom0 gets scheduled around, this wont match up with
the pcpus across the host.
~Andrew