Re: Patch "s390: select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP" has been added to the 6.1-stable tree

[Gerald Schaefer <gerald.schaefer@linux.ibm.com>]

On Sun, 22 Feb 2026 18:51:14 -0500
Sasha Levin <sashal@kernel.org> wrote:

> This is a note to let you know that I've just added the patch titled
> 
>     s390: select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
> 
> to the 6.1-stable tree which can be found at:
>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> 
> The filename of the patch is:
>      s390-select-arch_want_hugetlb_page_optimize_vmemmap.patch
> and it can be found in the queue-6.1 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.

Please don't add this to any stable tree. This feature is broken on s390,
and it recently was removed upstream via commit 64e2f60f355e ("s390:
Disable ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP"), which also had a Cc: stable
and Fixes: 00a34d5a99c0.

So we'd rather want commit 64e2f60f355e added to stable v6.2+, than
adding the original commit 00a34d5a99c0 to older trees.

Thanks,
Gerald