Re: [PATCH 3/7] x86/enter: Use IBRS on syscall and interrupts

[Greg KH]

On Thu, Jan 04, 2018 at 09:56:44AM -0800, Tim Chen wrote:
> 
> That is a minor inefficiency only, but we can eliminate it by saving
> the MSR when entering the NMI in save_paranoid and restoring it when
> exiting the NMI.

Any hints as to what exactly "minor" means in cycles here?  :)

thanks,

greg k-h