diff options
| author | Pasha Tatashin <pasha.tatashin@soleen.com> | 2025-11-14 14:00:02 -0500 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-11-27 14:24:37 -0800 |
| commit | 7bd3643f94a357863beef646b85cf10292398629 (patch) | |
| tree | abe596233647010fe9e8b7294184cdeea53729a5 | |
| parent | de51999e687c70a41997124b43291f84324c7924 (diff) | |
kho: add Kconfig option to enable KHO by default
Currently, Kexec Handover must be explicitly enabled via the kernel
command line parameter `kho=on`.
For workloads that rely on KHO as a foundational requirement (such as the
upcoming Live Update Orchestrator), requiring an explicit boot parameter
adds redundant configuration steps.
Introduce CONFIG_KEXEC_HANDOVER_ENABLE_DEFAULT. When selected, KHO
defaults to enabled. This is equivalent to passing kho=on at boot. The
behavior can still be disabled at runtime by passing kho=off.
Link: https://lkml.kernel.org/r/20251114190002.3311679-14-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Coiby Xu <coxu@redhat.com>
Cc: Dave Vasilevsky <dave@vasilevsky.ca>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Kees Cook <kees@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | kernel/liveupdate/Kconfig | 14 | ||||
| -rw-r--r-- | kernel/liveupdate/kexec_handover.c | 2 |
2 files changed, 15 insertions, 1 deletions
diff --git a/kernel/liveupdate/Kconfig b/kernel/liveupdate/Kconfig index eae428309332..a973a54447de 100644 --- a/kernel/liveupdate/Kconfig +++ b/kernel/liveupdate/Kconfig @@ -37,4 +37,18 @@ config KEXEC_HANDOVER_DEBUGFS Also, enables inspecting the KHO fdt trees with the debugfs binary blobs. +config KEXEC_HANDOVER_ENABLE_DEFAULT + bool "Enable kexec handover by default" + depends on KEXEC_HANDOVER + help + Enable Kexec Handover by default. This avoids the need to + explicitly pass 'kho=on' on the kernel command line. + + This is useful for systems where KHO is a prerequisite for other + features, such as Live Update, ensuring the mechanism is always + active. + + The default behavior can still be overridden at boot time by + passing 'kho=off'. + endmenu diff --git a/kernel/liveupdate/kexec_handover.c b/kernel/liveupdate/kexec_handover.c index a7f876ece445..224bdf5becb6 100644 --- a/kernel/liveupdate/kexec_handover.c +++ b/kernel/liveupdate/kexec_handover.c @@ -52,7 +52,7 @@ union kho_page_info { static_assert(sizeof(union kho_page_info) == sizeof(((struct page *)0)->private)); -static bool kho_enable __ro_after_init; +static bool kho_enable __ro_after_init = IS_ENABLED(CONFIG_KEXEC_HANDOVER_ENABLE_DEFAULT); bool kho_is_enabled(void) { |