diff options
| author | Pasha Tatashin <pasha.tatashin@soleen.com> | 2025-12-30 11:14:02 -0500 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-01-26 19:07:10 -0800 |
| commit | 998be0a4dbcaa796a05c7b52327f3a09c29d3662 (patch) | |
| tree | f70609f0500210049402d1745315c6b8173cd3e0 | |
| parent | 1921044eebf1d6861a6de1a76e3f63729a45e712 (diff) | |
liveupdate: separate memfd support into LIVEUPDATE_MEMFD
Decouple memfd preservation support from the core Live Update Orchestrator
configuration.
Previously, enabling CONFIG_LIVEUPDATE forced a dependency on CONFIG_SHMEM
and unconditionally compiled memfd_luo.o. However, Live Update may be
used for purposes that do not require memfd-backed memory preservation.
Introduce CONFIG_LIVEUPDATE_MEMFD to gate memfd_luo.o. This moves the
SHMEM and MEMFD_CREATE dependencies to the specific feature that needs
them, allowing the base LIVEUPDATE option to be selected independently of
shared memory support.
Link: https://lkml.kernel.org/r/20251230161402.1542099-1-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | kernel/liveupdate/Kconfig | 17 | ||||
| -rw-r--r-- | mm/Makefile | 2 |
2 files changed, 17 insertions, 2 deletions
diff --git a/kernel/liveupdate/Kconfig b/kernel/liveupdate/Kconfig index d2aeaf13c3ac..1a8513f16ef7 100644 --- a/kernel/liveupdate/Kconfig +++ b/kernel/liveupdate/Kconfig @@ -54,7 +54,6 @@ 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 @@ -73,4 +72,20 @@ config LIVEUPDATE If unsure, say N. +config LIVEUPDATE_MEMFD + bool "Live update support for memfd" + depends on LIVEUPDATE + depends on MEMFD_CREATE + depends on SHMEM + default LIVEUPDATE + help + Enable live update support for memfd regions. This allows preserving + memfd-backed memory across kernel live updates. + + This can be used to back VM memory with memfds, allowing the guest + memory to persist, or for other user workloads needing to preserve + pages. + + If unsure, say N. + endmenu diff --git a/mm/Makefile b/mm/Makefile index 2d0570a16e5b..e38fcfbb805c 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -100,7 +100,7 @@ obj-$(CONFIG_NUMA) += memory-tiers.o obj-$(CONFIG_DEVICE_MIGRATION) += migrate_device.o obj-$(CONFIG_TRANSPARENT_HUGEPAGE) += huge_memory.o khugepaged.o obj-$(CONFIG_PAGE_COUNTER) += page_counter.o -obj-$(CONFIG_LIVEUPDATE) += memfd_luo.o +obj-$(CONFIG_LIVEUPDATE_MEMFD) += memfd_luo.o obj-$(CONFIG_MEMCG_V1) += memcontrol-v1.o obj-$(CONFIG_MEMCG) += memcontrol.o vmpressure.o ifdef CONFIG_SWAP |