Re: [PATCH 1/8] x86/mm/cpa: Use flush_tlb_all()

[Peter Zijlstra]

On Wed, Sep 19, 2018 at 10:50:17AM +0200, Peter Zijlstra wrote:
> Instead of open-coding it..
> 
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> ---
>  arch/x86/mm/pageattr.c |   12 +-----------
>  1 file changed, 1 insertion(+), 11 deletions(-)
> 
> --- a/arch/x86/mm/pageattr.c
> +++ b/arch/x86/mm/pageattr.c
> @@ -285,16 +285,6 @@ static void cpa_flush_all(unsigned long
>  	on_each_cpu(__cpa_flush_all, (void *) cache, 1);
>  }
>  
> -static void __cpa_flush_range(void *arg)
> -{
> -	/*
> -	 * We could optimize that further and do individual per page
> -	 * tlb invalidates for a low number of pages. Caveat: we must
> -	 * flush the high aliases on 64bit as well.
> -	 */
> -	__flush_tlb_all();
> -}

Hmm,.. so in patch #4 I do switch to flush_tlb_kernel_range(). What are
those high aliases that comment talks about?