On 12/23/20 7:57 AM, Chang S. Bae wrote: > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 44fde25bb221..a67ae04d43c5 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -6002,6 +6002,21 @@ > 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 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. ? thanks. -- ~Randy
