[PATCH v10 08/11] build: Add modules.builtin.alias

[Allen Webb <allenwebb@google.com>]

Generate modules.builtin.alias using modpost and install it with the
modules.

Signed-off-by: Allen Webb <allenwebb@google.com>
---
 .gitignore               |  1 +
 Makefile                 |  1 +
 scripts/Makefile.modpost | 15 +++++++++++++++
 3 files changed, 17 insertions(+)

diff --git a/.gitignore b/.gitignore
index 13a7f08a3d73..ddaa622bddac 100644
--- a/.gitignore
+++ b/.gitignore
@@ -71,6 +71,7 @@ modules.order
 /System.map
 /Module.markers
 /modules.builtin
+/modules.builtin.alias
 /modules.builtin.modinfo
 /modules.nsdeps
 
diff --git a/Makefile b/Makefile
index a2c310df2145..43dcc1ea5fcf 100644
--- a/Makefile
+++ b/Makefile
@@ -1578,6 +1578,7 @@ __modinst_pre:
 	fi
 	@sed 's:^\(.*\)\.o$$:kernel/\1.ko:' modules.order > $(MODLIB)/modules.order
 	@cp -f modules.builtin $(MODLIB)/
+	@cp -f modules.builtin.alias $(MODLIB)/
 	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
 
 endif # CONFIG_MODULES
diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
index 0980c58d8afc..e3ecc17a7a19 100644
--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -15,6 +15,7 @@
 # 2) modpost is then used to
 # 3)  create one <module>.mod.c file per module
 # 4)  create one Module.symvers file with CRC for all exported symbols
+# 5)  create modules.builtin.alias the aliases for built-in modules
 
 # Step 3 is used to place certain information in the module's ELF
 # section, including information such as:
@@ -63,6 +64,20 @@ modpost-args += -T $(MODORDER)
 modpost-deps += $(MODORDER)
 endif
 
+ifneq ($(wildcard vmlinux.o),)
+output-builtin.alias := modules.builtin.alias
+modpost-args += -b .modules.builtin.alias.in
+.modules.builtin.alias.in: $(output-symdump)
+	@# Building $(output-symdump) generates .modules.builtin.alias.in as a
+	@# side effect.
+	@[ -e $@ ] || $(MODPOST) -b .modules.builtin.alias.in vmlinux.o
+
+$(output-builtin.alias): .modules.builtin.alias.in
+	sort -o $@ $^
+
+__modpost: $(output-builtin.alias)
+endif
+
 ifeq ($(KBUILD_EXTMOD),)
 
 # Generate the list of in-tree objects in vmlinux
-- 
2.39.2