Re: [PATCH V3] selftests: vm: Add test for Soft-Dirty PTE bit

[Shuah Khan]

On 3/3/22 11:39 AM, Gabriel Krisman Bertazi wrote:
> Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> writes:
>
> > On 2/28/22 2:37 AM, David Hildenbrand wrote:
> > > On 24.02.22 22:23, Muhammad Usama Anjum wrote:
> > > > This introduces three tests:
> > > > 1) Sanity check soft dirty basic semantics: allocate area, clean, dirty,
> > > > check if the SD bit flipped.
> > > > 2) Check VMA reuse: validate the VM_SOFTDIRTY usage
> > > > 3) Check soft-dirty on huge pages
> > > >
> > > > This was motivated by Will Deacon's fix commit 912efa17e512 ("mm: proc:
> > > > Invalidate TLB after clearing soft-dirty page state"). I was tracking the
> > > > same issue that he fixed, and this test would have caught it.
> > > A note that madv_populate.c already contains some SOFTDIRTY tests
> > > regarding MADV_POPULATE. Eventually we want to factor out
> > > softdirty/pagemap handling+checks for easier reuse.
> >
> > Is this patch unnecessary then?
>
> It is not unnecessary since the madv test doesn't cover the bug tested
> here, afaik.  But, as mentioned when I originally submitted this patch,
> it should be merged into selftests/vm/madv_populate.c or, at least,
> reuse that existing infrastructure.
>
> https://lore.kernel.org/lkml/87lf553z5g.fsf@xxxxxxxxxxxxx/

Oops this one came in a few months ago and appears to have slipped
through and didn't get the right attention. Sorry about that.

Please resend the patch and cc all the everybody on this thread.

I would like to have your patch reviewed and looked at first. This
patch needs rework sine it has several comments to be addressed.

thanks,
-- Shuah