Re: [PATCH 4/7] x86/idle: Disable IBRS entering idle and enable it on wakeup

Andrea Arcangeli
2018-01-04T23:42:31Z

On Thu, Jan 04, 2018 at 03:22:09PM -0800, Tim Chen wrote:
> No one should be calling this with IRQs enabled. This check is probably
> just paranoid. I can get rid of it.

Yes, confirmed.

> It probably doesn't matter as we will be switching the check
> to the spec_ctrl_ibrs a couple of patches later.

The other problem with static_cpu_has is later the code intends to
support the cpuid rescan post late microcode update which will set
bits in boot_cpu_data (and transfer them to each cpu_has). If we'd
only support early microcode update static_cpu_has should have been ok
too.