Re: [Xen-devel] [PATCH] x86: allow easier disabling of BTI mitigations

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 01/02/18 08:52, Jan Beulich wrote:
> @@ -268,6 +271,8 @@ functionality is still set up so IBRS ca
>  On hardware supporting IBPB, the `ibpb=` option can be used to prevent Xen
>  from issuing Branch Prediction Barriers on vcpu context switches.
>  
> +The `rsb=` option can be used to uniformly suppress RSB overwriting.
> +
>  The `rsb_vmexit=` and `rsb_native=` options can be used to fine tune when the
>  RSB gets overwritten.  There are individual controls for an entry from HVM
>  context, and an entry from a native (PV or Xen) context.

It would probably be  better to merge your change into this paragraph. 
How about:

The `rsb=`, `rsb_vmexit=` and `rsb_native=` options can be used to
control when the RSB gets overwritten.  The former control all RSB
overwriting, while the latter two can be used to fine tune overwriting
on from HVM context, and an entry from a native (PV or Xen) context.

?

Otherwise, Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

I really need to find some time to implement bti=hvm-only

~Andrew

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel