Re: [PATCH] fs/proc/task_mmu: fix missed VMAs when reading /proc/PID/maps and friends

[Lorenzo Stoakes (ARM)]

On Mon, Oct 26, 2026 at 06:19:18PM +0100, David Hildenbrand (Arm) wrote:
> >> +       /*
> >> +        * No lock was held since the last call, so the iterator's cached range
> >> +        * may no longer be valid. Always restart by address.
> >> +        *
> >> +        * The vma_range_is_empty() checks below avoid unnecessary mmap_lock
> >> +        * fallbacks.
> >> +        */
> >> +       vma_iter_set(vmi, from_addr);
> >
> > This is clearly simpler but this unconditional vmi reset is not ideal.
>
> Yes, exactly how I ended up where we am right now.
>
> I pref my current fix as something to backport that avoids performance changes.
>
> If you two disagree, please take it over and drag it over the finishing line in
> a timely manner.
>
> I wasted enough of my weekend with this over-enginered piece of software. (had
> to change one word before sending, can you guess which :P )

No problem, will take over.

--
Cheers, Lorenzo