Re: [RFC 11/20] mm/tlb: remove arch-specific tlb_start/end_vma()

Peter Zijlstra
2021-02-02T11:05:07Z

On Tue, Feb 02, 2021 at 09:54:36AM +0000, Nadav Amit wrote:
> > On Feb 2, 2021, at 1:31 AM, Peter Zijlstra <peterz@infradead.org> wrote:
> >
> > On Tue, Feb 02, 2021 at 07:20:55AM +0000, Nadav Amit wrote:
> >> Arm does not define tlb_end_vma, and consequently it flushes the TLB after
> >> each VMA. I suspect it is not intentional.
> >
> > ARM is one of those that look at the VM_EXEC bit to explicitly flush
> > ITLB IIRC, so it has to.
>
> Hmm… I don’t think Arm is doing that. At least arm64 does not use the
> default tlb_flush(), and it does not seem to consider VM_EXEC (at least in
> this path):
>

ARM != ARM64. ARM certainly does, but you're right, I don't think ARM64
does this.