+ mm-memfd_luo-add-config_shmem-dependency.patch added to mm-nonmm-unstable branch

+ mm-memfd_luo-add-config_shmem-dependency.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: memfd_luo: add CONFIG_SHMEM dependency
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     mm-memfd_luo-add-config_shmem-dependency.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memfd_luo-add-config_shmem-dependency.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Arnd Bergmann <arnd@arndb.de>
Subject: mm: memfd_luo: add CONFIG_SHMEM dependency
Date: Thu, 4 Dec 2025 11:01:58 +0100

The new memfd code fails to link without SHMEM:

aarch64-linux-ld: mm/memfd_luo.o: in function `memfd_luo_retrieve_folios':
memfd_luo.c:(.text.memfd_luo_retrieve_folios+0xdc): undefined reference to `shmem_add_to_page_cache'
memfd_luo.c:(.text.memfd_luo_retrieve_folios+0x11c): undefined reference to `shmem_inode_acct_blocks'
memfd_luo.c:(.text.memfd_luo_retrieve_folios+0x134): undefined reference to `shmem_recalc_inode'

Add a Kconfig dependency to disallow that configuration.

Link: https://lkml.kernel.org/r/20251204100203.1034394-1-arnd@kernel.org
Fixes: b3749f174d68 ("mm: memfd_luo: allow preserving memfd")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/liveupdate/Kconfig |    1 +
 1 file changed, 1 insertion(+)

--- a/kernel/liveupdate/Kconfig~mm-memfd_luo-add-config_shmem-dependency
+++ a/kernel/liveupdate/Kconfig
@@ -54,6 +54,7 @@ config KEXEC_HANDOVER_ENABLE_DEFAULT
 config LIVEUPDATE
 	bool "Live Update Orchestrator"
 	depends on KEXEC_HANDOVER
+	depends on SHMEM
 	help
 	  Enable the Live Update Orchestrator. Live Update is a mechanism,
 	  typically based on kexec, that allows the kernel to be updated
_

Patches currently in -mm which might be from arnd@arndb.de are

mm-damon-tests-core-kunit-avoid-damos_test_commit-stack-warning.patch
mm-shmem-avoid-build-warning-for-config_shmem=n.patch
mm-memfd_luo-add-config_shmem-dependency.patch