Hi--
On 10/1/20 1:39 PM, Chang S. Bae wrote:
> diff --git a/Documentation/admin-guide/kernel-parameters.txt
> b/Documentation/admin-guide/kernel-parameters.txt
> index a1068742a6df..742167c6f789 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -5838,6 +5838,21 @@
> which allow the hypervisor to 'idle' the guest on lock
> contention.
>
> + xstate.enable= [X86-64]
> + xstate.disable= [X86-64]
> + The kernel is compiled with a default xstate bitmask --
> + enabling it to use the XSAVE hardware to efficiently
> + save and restore thread states on context switch.
> + xstate.enable allows adding to that default mask at
> + boot-time without recompiling the kernel just to support
> + the new thread state. (Note that the kernel will ignore
> + any bits in the mask that do not correspond to features
> + that are actually available in CPUID) xstate.disable
in CPUID.)
> + allows clearing bits in the default mask, forcing the
> + kernel to forget that it supports the specified thread
> + state. When a bit set for both, the kernel takes
> + xstate.disable in a priority.
as a priority.
What do these bitmasks look like? what do the bits mean?
Where does a user find this info?
thanks.
--
~Randy
