Re: [PATCH v4] mm/gup: honour FOLL_PIN in NOMMU __get_user_pages_locked()

[David Hildenbrand <david@kernel.org>]

On Mon, 21 Sep 2026 11:57:29 +0200, David Hildenbrand (Arm) wrote:
> The !CONFIG_MMU implementation of __get_user_pages_locked() takes a bare
> get_page() reference for each page regardless of foll_flags:
> 	if (pages[i])
> 		get_page(pages[i]);
> 
> This is reached from pin_user_pages*() with FOLL_PIN set.
> unpin_user_page() is shared between MMU and NOMMU configurations and
> unconditionally calls gup_put_folio(..., FOLL_PIN), which subtracts
> GUP_PIN_COUNTING_BIAS (1024) from the folio refcount.
> 
> [...]

Applied, thanks!

tree: mm/core.git
branch: gup-7.4.misc

Applied patches will appear soon in mm-next, followed by linux-next.

Please report any outstanding bugs that were missed during review, so we
can either drop the patch series or decide how to fix it up.

It is encouraged to provide Acked-bys, Reviewed-bys, and Tested-bys even
though the patches have already been applied. If possible, patch trailers
will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. Further, this is not a guarantee that the
patches will go upstream. If in doubt, please check the listed branch.

[1/1] mm/gup: honour FOLL_PIN in NOMMU __get_user_pages_locked()
      https://git.kernel.org/mm/core/c/da01399b

-- 
Cheers,

David