Re: [PATCH] x86/mm: Drop usage of __flush_tlb_all() in kernel_physical_mapping_init()

From: Dan Williams
Date: Mon Nov 19 2018 - 18:48:47 EST


On Mon, Nov 19, 2018 at 3:43 PM Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
>
> On 11/19/18 3:19 PM, Dan Williams wrote:
> > Andy wondered why a path that can sleep was using __flush_tlb_all() [1]
> > and Dave confirmed the expectation for TLB flush is for modifying /
> > invalidating existing pte entries, but not initial population [2].
>
> I _think_ this is OK.
>
> But, could we sprinkle a few WARN_ON_ONCE(p*_present()) calls in there
> to help us sleep at night?

Makes sense, I'll add those for v2.