Re: [PATCH] io_uring: take page references for NOMMU pbuf_ring mmaps

Jens Axboe
2026-04-21T13:50:34Z

On 4/21/26 7:46 AM, Greg Kroah-Hartman wrote:
> Note, I have no way of testing this, I'm only forwarding this on because
> I got the bug report and was able to generate something that "seems"

AI bug report I presume? Because I can't imagine anyone ever attempted
to run this.

> correct, but it might be a total load of crap here, my knowledge of the
> vm layer is very low so take this for where it is coming from (i.e. a
> non-deterministic pattern matching system.)
>
> I do have another patch that just disables io_uring for !MMU systems, if
> you want that instead? Or is this feature something that !MMU devices
> actually care about?

I mean, who really cares about !MMU in the first place, we should just
kill that off with a passion.

Let me take a closer look at this and bounce it past some vm people, my
nommu knowledge is close to zero as it's never been relevant in my
professional life time. Which is saying something...

--
Jens Axboe