modpost: Add modname to mod_device_table alias

At this point, if a symbol is compiled as part of the kernel,
information about which module the symbol belongs to is lost.

To save this it is possible to add the module name to the alias name.
It's not very pretty, but it's possible for now.

Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: rust-for-linux@vger.kernel.org
Signed-off-by: Alexey Gladkov <legion@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Nicolas Schier <nsc@kernel.org>
Link: https://patch.msgid.link/1a0d0bd87a4981d465b9ed21e14f4e78eaa03ded.1758182101.git.legion@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>

diff --git a/include/linux/module.h b/include/linux/module.h
index 3319a5269d2865747f0c8ade04394a600303a2ce..e31ee29fac6b755464713d9e8aa4a604b30a24b2 100644 (file)
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -244,10 +244,22 @@ struct module_kobject *lookup_or_create_module_kobject(const char *name);
 /* What your module does. */
 #define MODULE_DESCRIPTION(_description) MODULE_INFO(description, _description)
 
+/*
+ * Format: __mod_device_table__kmod_<modname>__<type>__<name>
+ * Parts of the string `__kmod_` and `__` are used as delimiters when parsing
+ * a symbol in file2alias.c
+ */
+#define __mod_device_table(type, name) \
+       __PASTE(__mod_device_table__,   \
+       __PASTE(__KBUILD_MODNAME,       \
+       __PASTE(__,                     \
+       __PASTE(type,                   \
+       __PASTE(__, name)))))
+
 #ifdef MODULE
 /* Creates an alias so file2alias.c can find device table. */
 #define MODULE_DEVICE_TABLE(type, name)                                        \
-static typeof(name) __mod_device_table__##type##__##name               \
+static typeof(name) __mod_device_table(type, name)                     \
   __attribute__ ((used, alias(__stringify(name))))
 #else  /* !MODULE */
 #define MODULE_DEVICE_TABLE(type, name)

diff --git a/rust/kernel/device_id.rs b/rust/kernel/device_id.rs
index 70d57814ff79bb279c025b379c6ba639a8ce7d1a..62c42da12e9deccd7c402f53417f90f922b3f2be 100644 (file)
--- a/rust/kernel/device_id.rs
+++ b/rust/kernel/device_id.rs
@@ -195,10 +195,10 @@ macro_rules! module_device_table {
     ($table_type: literal, $module_table_name:ident, $table_name:ident) => {
         #[rustfmt::skip]
         #[export_name =
-            concat!("__mod_device_table__", $table_type,
-                    "__", module_path!(),
-                    "_", line!(),
-                    "_", stringify!($table_name))
+            concat!("__mod_device_table__", line!(),
+                    "__kmod_", module_path!(),
+                    "__", $table_type,
+                    "__", stringify!($table_name))
         ]
         static $module_table_name: [::core::mem::MaybeUninit<u8>; $table_name.raw_ids().size()] =
             unsafe { ::core::mem::transmute_copy($table_name.raw_ids()) };

diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 00586119a25b7fd399eeeef3760a26467ffbb50c..1260bc2287fba5eda236695f5d71b42603f5499f 100644 (file)
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1476,7 +1476,7 @@ void handle_moddevtable(struct module *mod, struct elf_info *info,
 {
        void *symval;
        char *zeros = NULL;
-       const char *type, *name;
+       const char *type, *name, *modname;
        size_t typelen;
        static const char *prefix = "__mod_device_table__";
 
@@ -1488,10 +1488,19 @@ void handle_moddevtable(struct module *mod, struct elf_info *info,
        if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT)
                return;
 
-       /* All our symbols are of form __mod_device_table__<type>__<name>. */
+       /* All our symbols are of form __mod_device_table__kmod_<modname>__<type>__<name>. */
        if (!strstarts(symname, prefix))
                return;
-       type = symname + strlen(prefix);
+
+       modname = strstr(symname, "__kmod_");
+       if (!modname)
+               return;
+       modname += strlen("__kmod_");
+
+       type = strstr(modname, "__");
+       if (!type)
+               return;
+       type += strlen("__");
 
        name = strstr(type, "__");
        if (!name)