Re: [v3] fs/proc/task_mmu: Implement IOCTL for efficient page table scanning

[Michał Mirosław]

On Tue, 25 Jul 2023 at 11:11, Muhammad Usama Anjum
<usama.anjum@xxxxxxxxxxxxx> wrote:
>
> ----
> Michal please post your thoughts before I post this as v26.
> ----
[...]

Looks ok - minor things below.

1. I'd change the _WPASYNC things to something better, if this can
also work with "normal" UFFD WP.

2. For the address tagging part I'd prefer someone who knows how this
is used take a look. We're ignoring the tag (but clear it on return in
->start) - so it doesn't matter for the ioctl() itself.

3. BTW, One of the uses is the GetWriteWatch and I wonder how it
behaves on HugeTLB (MEM_LARGE_PAGES allocation)? Shouldn't it return a
list of huge pages and write *lpdwGranularity = HPAGE_SIZE?

4. The docs and commit messages need some rewording due to the changes
in the API.

Other than that:

Reviewed-by: Michał Mirosław <mirq-linux@xxxxxxxxxxxx>