Add a `prebuilt_kernel_modules` prop to skip debug symbol strip

`Strip_debug_symbols` will default to true. If this property is set to
false explicitly, the .ko files will be installed without running
llvm-strip. The use case for this is (system|vendor|odm)_dlkm
filesystems, which package the source *.ko files without stripping
debug symbols.

This CL also fixes a bug where the output of `addLeadingSlashToPaths`
was getting ignored, since it assigned its output to a variable that was
scoped locally (via :=) instead of updating the variable in its outer
scope (via =)

Bug: 383357338
Test: mounted system_dlkm, vendor_dlkm, odm_dlkm image files built by
make and soong (top of CL stack). NOTICE is the last diff.

Change-Id: Ie5ecef0c3f6d024fe413106e17f22dee3fb18d61

1 files changed, 11 insertions, 5 deletions

diff --git a/kernel/prebuilt_kernel_modules.go b/kernel/prebuilt_kernel_modules.go
index 001a1e732..ec7a9714b 100644
--- a/kernel/prebuilt_kernel_modules.go
+++ b/kernel/prebuilt_kernel_modules.go
@@ -67,6 +67,10 @@ type prebuiltKernelModulesProperties struct {
 
 	// Whether this module is directly installable to one of the partitions. Default is true
 	Installable *bool
+
+	// Whether debug symbols should be stripped from the *.ko files.
+	// Defaults to true.
+	Strip_debug_symbols *bool
 }
 
 // prebuilt_kernel_modules installs a set of prebuilt kernel module files to the correct directory.
@@ -100,7 +104,9 @@ func (pkm *prebuiltKernelModules) GenerateAndroidBuildActions(ctx android.Module
 	systemModules := android.PathsForModuleSrc(ctx, pkm.properties.System_deps)
 
 	depmodOut := pkm.runDepmod(ctx, modules, systemModules)
-	strippedModules := stripDebugSymbols(ctx, modules)
+	if proptools.BoolDefault(pkm.properties.Strip_debug_symbols, true) {
+		modules = stripDebugSymbols(ctx, modules)
+	}
 
 	installDir := android.PathForModuleInstall(ctx, "lib", "modules")
 	// Kernel module is installed to vendor_ramdisk/lib/modules regardless of product
@@ -114,7 +120,7 @@ func (pkm *prebuiltKernelModules) GenerateAndroidBuildActions(ctx android.Module
 		installDir = installDir.Join(ctx, pkm.KernelVersion())
 	}
 
-	for _, m := range strippedModules {
+	for _, m := range modules {
 		ctx.InstallFile(installDir, filepath.Base(m.String()), m)
 	}
 	ctx.InstallFile(installDir, "modules.load", depmodOut.modulesLoad)
@@ -165,9 +171,9 @@ var (
 		}, "stripCmd")
 )
 
-func stripDebugSymbols(ctx android.ModuleContext, modules android.Paths) android.OutputPaths {
+func stripDebugSymbols(ctx android.ModuleContext, modules android.Paths) android.Paths {
 	dir := android.PathForModuleOut(ctx, "stripped").OutputPath
-	var outputs android.OutputPaths
+	var outputs android.Paths
 
 	for _, m := range modules {
 		stripped := dir.Join(ctx, filepath.Base(m.String()))
@@ -305,7 +311,7 @@ func (pkm *prebuiltKernelModules) runDepmod(ctx android.ModuleContext, modules a
 	finalModulesDep := modulesDep
 	// Add a leading slash to paths in modules.dep of android dlkm
 	if ctx.InstallInSystemDlkm() || ctx.InstallInVendorDlkm() || ctx.InstallInOdmDlkm() {
-		finalModulesDep := modulesDep.ReplaceExtension(ctx, "intermediates")
+		finalModulesDep = modulesDep.ReplaceExtension(ctx, "intermediates")
 		ctx.Build(pctx, android.BuildParams{
 			Rule:   addLeadingSlashToPaths,
 			Input:  modulesDep,