Re: [PATCH v3 4/4] mm/page_table_check: check entries at pmd levels

[Pasha Tatashin]

On Wed, Jan 26, 2022 at 1:45 AM David Rientjes <rientjes@xxxxxxxxxx> wrote:
>
> On Wed, 26 Jan 2022, Pasha Tatashin wrote:
>
> > syzbot detected a case where the page table counters were not properly
> > updated.
> >
>
> Is there a Reported-by tag that syzbot wants us to use to track this?

Google internal syzbot found it, so I did not add Reported-by as there
is no  public e-mail to reference. However, I added all the necessary
steps to repro this problem to the cover letter.

>
>
> This looks right, I'm wondering if we want to add a
> mmap_assert_write_locked(mm) to collapse_and_free_pmd().

Good idea, I will add it in the next revision.

Thanks,
Pasha