Re: [PATCH 2/7] MAINTAINERS: TMPFS (SHMEM FILESYSTEM) updates

[Hugh Dickins <hughd@google.com>]

On Fri, 30 Oct 2026, David Hildenbrand (Arm) wrote:

> I am not really the best shmem/tmpfs/memfd expert around, but it should
> be good enough to judge when something is ready to be picked up, to then
> pick it up. I'll have to heavily rely on Hugh and Baolin on judgment
> for the more involved and more controversial bits.
> 
> Rename "TMPFS (SHMEM FILESYSTEM)" to "MEMORY MANAGEMENT - SHARED MEMORY
> (SHMEM/TMPFS/MEMFD)" and move it accordingly. Add myself as a MAINTAINER
> so people know whom to CC.

Thank you for taking this on, David. And thank you of course to the
unlisted Andrew Morton, who has been uncomplainingly filling in for
me year after year; and thank you to Baolin too.

"SHARED MEMORY": should ipc/shm.c be added to our list of files below,
as mm/memfd.c is? (Though both can also go off to hugetlbfs instead.)
Or do you prefer to regard ipc/shm.c more as a client of mm/shmem.c,
rather as drivers/gpu/drm is?

We don't often have to touch ipc/shm.c, and generally ipc/ is well cared
for by Manfred Spraul (but I couldn't see a block in MAINTAINERS for it).

> 
> Add mm/core.git as the target git tree. Once shmem becomes a high volume
> component we can dedicate it a separate tree and have dedicated people
> pick it up.

Okay: but do keep in mind that tmpfs is a filesystem, and often the
FS folks make small adjustments to it, which usually go unconflictingly
through Christian Brauner's tree. That generally works well, so please
let's keep on working in that way (just once I remember holding off
intended MM changes to shmem.c for a release, while FS were busy there).

> 
> While at it, add some more shmem/tmpfs/memfd related files+directories
> we missed so far.
> 
> There is also "kernel/pid_sysctl.h", which includes some of the pid
> namespaced sysctl vm.memfd_noexec. But that's really more of a proc/
> namespace thingy, so it's not a good fit here.

Agreed: if I ever heard of it, I soon forgot.

> 
> Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>

Acked-by: Hugh Dickins <hughd@google.com>

> ---
>  MAINTAINERS | 30 +++++++++++++++++++-----------
>  1 file changed, 19 insertions(+), 11 deletions(-)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index dbb5582ec1c74..0baeb37b0dcdc 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -17772,6 +17772,25 @@ S:	Maintained
>  F:	include/linux/secretmem.h
>  F:	mm/secretmem.c
>  
> +MEMORY MANAGEMENT - SHARED MEMORY (SHMEM/TMPFS/MEMFD)
> +M:	Hugh Dickins <hughd@google.com>
> +M:	David Hildenbrand <david@kernel.org>
> +R:	Baolin Wang <baolin.wang@linux.alibaba.com>
> +L:	linux-mm@kvack.org
> +S:	Maintained
> +T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mm/core.git for-next
> +F:	Documentation/filesystems/tmpfs.rst
> +F:	Documentation/mm/shmfs.rst
> +F:	Documentation/userspace-api/mfd_noexec.rst
> +F:	include/linux/memfd.h
> +F:	include/linux/shmem_fs.h
> +F:	include/uapi/linux/memfd.h
> +F:	mm/memfd.c
> +F:	mm/shmem.c
> +F:	mm/shmem_quota.c
> +F:	tools/testing/selftests/memfd/
> +F:	tools/testing/selftests/tmpfs/
> +
>  MEMORY MANAGEMENT - SWAP
>  M:	Andrew Morton <akpm@linux-foundation.org>
>  M:	Chris Li <chrisl@kernel.org>
> @@ -28202,17 +28221,6 @@ S:	Maintained
>  F:	Documentation/hwmon/tmp513.rst
>  F:	drivers/hwmon/tmp513.c
>  
> -TMPFS (SHMEM FILESYSTEM)
> -M:	Hugh Dickins <hughd@google.com>
> -R:	Baolin Wang <baolin.wang@linux.alibaba.com>
> -L:	linux-mm@kvack.org
> -S:	Maintained
> -F:	include/linux/memfd.h
> -F:	include/linux/shmem_fs.h
> -F:	mm/memfd.c
> -F:	mm/shmem.c
> -F:	mm/shmem_quota.c
> -
>  TOMOYO SECURITY MODULE
>  M:	Kentaro Takeda <takedakn@nttdata.co.jp>
>  M:	Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> 
> -- 
> 2.43.0