kleaf: kernel_module restores Module.symvers to `COMMON_OUT_DIR`.

When ddk_module is building with --config=local:

- OUT_DIR is in out/cache/<hash>/$KERNEL_DIR
- Module.symvers of the depended module is restored to
  out/cache/<hash>/<package>/<name>_Module.symvers
- However, the generated makefile expects the file
  in COMMON_OUT_DIR/<package>/<name>_Module.symvers,
  where COMMON_OUT_DIR is not changed.

  This is because cache_dir.bzl only modifies the
  value of OUT_DIR, not COMMON_OUT_DIR.

Hence, let kernel_module's command to restore its
Module.symvers to use COMMON_OUT_DIR directly.

Bug: 304499217
Change-Id: I28995f30812e7ac2d596982d70e79f9374364787
Signed-off-by: Ulises Mendez Martinez <umendez@google.com>
Signed-off-by: Yifan Hong <elsk@google.com>
(cherry picked from commit 2f12101856d947353d043aec76ed0bf7c09e1c70)

2 files changed, 6 insertions, 5 deletions

diff --git a/kleaf/impl/common_providers.bzl b/kleaf/impl/common_providers.bzl
index fc5173f7..8dd23e52 100644
--- a/kleaf/impl/common_providers.bzl
+++ b/kleaf/impl/common_providers.bzl
@@ -318,8 +318,7 @@ ModuleSymversInfo = provider(
     doc = "A provider that provides `Module.symvers` for `modpost`.",
     fields = {
         "restore_paths": """A [depset](https://bazel.build/extending/depsets) of
-            paths relative to <the root of the output directory> (e.g.
-            `<sandbox_root>/out/<branch>`) where the `Module.symvers` files will be
+            paths relative to `COMMON_OUT_DIR` where the `Module.symvers` files will be
             restored to by `KernelModuleSetupInfo`.""",
     },
 )
diff --git a/kleaf/impl/kernel_module.bzl b/kleaf/impl/kernel_module.bzl
index 7d1975ce..cbd84df9 100644
--- a/kleaf/impl/kernel_module.bzl
+++ b/kleaf/impl/kernel_module.bzl
@@ -550,6 +550,7 @@ def _kernel_module_impl(ctx):
             progress_message = "Copying outputs {}".format(ctx.label),
         )
 
+    module_symvers_restore_path = paths.join(ext_mod, ctx.attr.internal_module_symvers_name)
     setup = """
              # Use a new shell to avoid polluting variables
                (
@@ -559,14 +560,15 @@ def _kernel_module_impl(ctx):
                mkdir -p ${{ROOT_DIR}}/{ext_mod}
                ext_mod_rel=$(realpath ${{ROOT_DIR}}/{ext_mod} --relative-to ${{KERNEL_DIR}})
              # Restore Modules.symvers
-               mkdir -p $(dirname ${{OUT_DIR}}/${{ext_mod_rel}}/{internal_module_symvers_name})
-               rsync -aL {module_symvers} ${{OUT_DIR}}/${{ext_mod_rel}}/{internal_module_symvers_name}
+               mkdir -p $(dirname ${{COMMON_OUT_DIR}}/{module_symvers_restore_path})
+               rsync -aL {module_symvers} ${{COMMON_OUT_DIR}}/{module_symvers_restore_path}
              # New shell ends
                )
     """.format(
         ext_mod = ext_mod,
         module_symvers = module_symvers.path,
         internal_module_symvers_name = ctx.attr.internal_module_symvers_name,
+        module_symvers_restore_path = module_symvers_restore_path,
     )
 
     if ctx.attr.internal_ddk_makefiles_dir:
@@ -615,7 +617,7 @@ def _kernel_module_impl(ctx):
             # path/to/package/target_name/target_name_Module.symvers -> path/to/package/target_name_Module.symvers;
             # This is similar to ${{OUT_DIR}}/${{ext_mod_rel}}
             # It is needed to remove the `target_name` because we declare_file({name}/{internal_module_symvers_name}) above.
-            restore_paths = depset([paths.join(ext_mod, ctx.attr.internal_module_symvers_name)]),
+            restore_paths = depset([module_symvers_restore_path]),
         ),
         ddk_headers_info,
         ddk_config_info,