Re: [PATCH v4 11/12] mm: make userland page table freeing RCU-safe

From: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
To: "David Hildenbrand (Arm)" <david@kernel.org>
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Subject: Re: [PATCH v4 11/12] mm: make userland page table freeing RCU-safe
Date: Wed, 23 Sep 2026 12:48:53 +0100	[thread overview]
Message-ID: <arO7lSy71meks_sW@gremlin> (raw)
In-Reply-To: <802d3999-95fe-4a09-89b4-d01b60f8e963@kernel.org>

On Wed, Sep 23, 2026 at 11:13:36AM +0200, David Hildenbrand (Arm) wrote:
> On 9/23/26 11:06, Lorenzo Stoakes (ARM) wrote:
> > On Wed, Sep 23, 2026 at 11:04:17AM +0200, David Hildenbrand (Arm) wrote:
> >> On 9/22/26 17:35, Lorenzo Stoakes (ARM) wrote:
> >>
> >> The patch subject confused me at first: that's not what the patch is doing, no?
> >> Previous patches did that, and now you're just removing the leftovers?
> >>
> >> Maybe I'm missing something that this patch does along the lines of teaching the
> >> code to be RCU-safe.
> >
> > It is the final piece that makes that the case, so I think it's OK to allow
> > oneself a nice subject line? No? :)
>
> Just took me longer to figure out if I am missing something important.
>
> E.g.,
>
> 	"mm: remove unused RCU-unsafe user page table freeing"
>
> would have been clearer to me. Anyhow, just stumbled over it, I don't care too much.

Compromise on:

mm: now userland pgtable freeing is safe, remove unused bits

?

>
> --
> Cheers,
>
> David

--
Cheers, Lorenzo