Re: [PATCH v2 0/3] Create 'old' ptes for faultaround mappings on arm64 with hardware access flag

[Will Deacon]

On Mon, Jan 11, 2021 at 01:03:29PM -0800, Hugh Dickins wrote:
> On Mon, 11 Jan 2021, Will Deacon wrote:
> > On Fri, Jan 08, 2021 at 11:34:08AM -0800, Linus Torvalds wrote:
> > > On Fri, Jan 8, 2021 at 9:15 AM Will Deacon <will@xxxxxxxxxx> wrote:
> > > >
> > > > The big difference in this version is that I have reworked it based on
> > > > Kirill's patch which he posted as a follow-up to the original. However,
> > > > I can't tell where we've landed on that -- Linus seemed to like it, but
> > > > Hugh was less enthusiastic.
> > > 
> > > Yeah, I like it, but I have to admit that it had a disturbingly high
> > > number of small details wrong for several versions. I hope you picked
> > > up the final version of the code.
> > 
> > I picked the version from here:
> > 
> >   https://lore.kernel.org/r/20201229132819.najtavneutnf7ajp@box
> > 
> > and actually, I just noticed that willy spotted a typo in a comment, so
> > I'll fix that locally as well as adding the above to a 'Link:' tag for
> > reference.
> > 
> > > At the same time, I do think that the "disturbingly high number of
> > > issues" was primarily exactly _because_ the old code was so
> > > incomprehensible, and I think the end result is much cleaner, so I
> > > still like it.
> 
> Just to report that I gave this v2 set a spin on a few (x86_64 and i386)
> machines, and found nothing objectionable this time around.

Thanks, Hugh.

> And the things that I'm unenthusiastic about are exactly those details
> that you and Kirill and Linus find unsatisfactory, but awkward to
> eliminate: expect no new insights from me!

Well, I'll keep you on CC for v3 -- just in case!

Will