[PATCH 2/6] module: add CONFIG_BUILTIN_RANGES option

From: Kris Van Hees
Date: Fri Dec 08 2023 - 00:12:02 EST


The CONFIG_BUILTIN_RANGES option controls whether offset range data is
generated for kernel modules that are built into the kernel image.

Signed-off-by: Kris Van Hees <kris.van.hees@xxxxxxxxxx>
Reviewed-by: Nick Alcock <nick.alcock@xxxxxxxxxx>
Reviewed-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
---
kernel/module/Kconfig | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig
index 33a2e991f608..0798439b11ac 100644
--- a/kernel/module/Kconfig
+++ b/kernel/module/Kconfig
@@ -389,4 +389,21 @@ config MODULES_TREE_LOOKUP
def_bool y
depends on PERF_EVENTS || TRACING || CFI_CLANG

+config BUILTIN_RANGES
+ bool "Generate address range information for builtin modules"
+ depends on VMLINUX_MAP
+ help
+ When modules are built into the kernel, there will be no module name
+ associated with its symbols in /proc/kallsyms. Tracers may want to
+ identify symbols by module name and symbol name regardless of whether
+ the module is configured as loadable or not.
+
+ This option generates modules.builtin.ranges in the build tree with
+ offset ranges (per ELF section) for the module(s) they belong to.
+ It also records an anchor symbol to determine the load address of the
+ section.
+
+ It is fully compatible with CONFIG_RANDOMIZE_BASE and similar late-
+ address-modification options.
+
endif # MODULES
--
2.42.0