Re: [RFC PATCH] ovl: keep merged and impure readdir caches separate

[Amir Goldstein]

On Thu, May 14, 2026 at 5:16 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote:
>
> On Thu, May 14, 2026 at 4:55 PM Nirmoy Das <nirmoyd@xxxxxxxxxx> wrote:
> > On 14.05.26 16:09, Amir Goldstein wrote:
> ...
> >> Patch looks great - real root cause, gave you minor comments.
> >>
> >> IIUC, as far as you know, the repro never triggered the theoretic
> >> OVL_WHITEOUTS race?
> >>
> >> It was always just this ERR_PTR(PTR_ERR()) black magic?
> >
> >
> > Yes, with this particular syzkaller reproducer, it was always this black magic. I tried with and without your suggested changes and saw no difference in the crash behavior.
> >
> > But I think we should also have the fix for OVL_WHITEOUTS race as well.
> >
>
> Yeh maybe.
> I don't like making fixes to theoretical races without reproducers.
> I'll think about it.
> Maybe I'll try to reproduce synthetically.
> Or maybe I'll just do a fortify patch.

FYI pushed readdir cache fortify patch to ovl-fixes in github.
It is based on the idea of your first patch, but implementation
is different.

Feel free to review.
I will post it later after testing and deciding what to do about the
"race fix" patch.

Thanks,
Amir.