Re: [PATCH 0/7] IBRS patch series

Paolo Bonzini
2018-01-05T11:32:18Z

On 04/01/2018 22:22, Van De Ven, Arjan wrote:
> this is about a level of paranoia you are comfortable with.
>
> Retpoline on Skylake raises the bar for the issue enormously, but
> there are a set of corner cases that exist and that are not trivial
> to prove you dealt with them.
>
> personally I am comfortable with retpoline on Skylake, but I would
> like to have IBRS as an opt in for the paranoid.
>

IBRS actually seems to perform more than decently on Skylake with the
microcode updates we're shipping in RHEL---much more so than Broadwell
or Haswell. Can you confirm that this is expected?

Paolo