On 4/29/25 14:49, Alexey Gladkov wrote: > On Tue, Apr 29, 2025 at 12:04:44PM +0200, Alexey Gladkov wrote: >>> I'm not sure it's best to overload this data in this way. I think mixing >>> actual files and "logical" modules in the modules list is somewhat >>> confusing. >>> >>> An alternative would be to keep a single module struct for vmlinux and >>> record the discovered aliases under it? >> >> It is possible to extend struct module_alias and add the module name. The >> problem is that alias is added by module_alias_printf() and we will have >> to add the module name to the arguments to each do_entry handler in >> addition to struct module where there is already a name (but in our case >> it is vmlinux). >> >> I can do that if you think it's a better way. > > If I don't add separate entries for each builtin module, the patch will > look like this: > [...]
I see, that didn't turn out as well as I envisioned. One more approach would be to track builtin modules separately. A patch is below. I'm not sure if it's better. diff --git a/include/linux/module.h b/include/linux/module.h index 7250b4a527ec..6225793ddcd4 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -257,14 +257,10 @@ extern void cleanup_module(void); __PASTE(type, \ __PASTE(__, name))))))) -#ifdef MODULE /* Creates an alias so file2alias.c can find device table. */ #define MODULE_DEVICE_TABLE(type, name) \ extern typeof(name) __mod_device_table(type, name) \ __attribute__ ((unused, alias(__stringify(name)))) -#else /* !MODULE */ -#define MODULE_DEVICE_TABLE(type, name) -#endif /* Version of form [<epoch>:]<version>[-<extra-version>]. * Or for CVS/RCS ID version, everything but the number is stripped. diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index dff1799a4c79..28a4c045f66c 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -1471,8 +1471,8 @@ static const struct devtable devtable[] = { /* Create MODULE_ALIAS() statements. * At this time, we cannot write the actual output C source yet, * so we write into the mod->dev_table_buf buffer. */ -void handle_moddevtable(struct module *mod, struct elf_info *info, - Elf_Sym *sym, const char *symname) +void handle_moddevtable(struct module *mod, struct elf_info *info, Elf_Sym *sym, + const char *symname) { void *symval; char *zeros = NULL; @@ -1509,6 +1509,10 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, typelen = name - type; name += strlen("__"); + if (mod->is_vmlinux) + // XXX Check if the module doesn't already exist? + mod = new_module(modname, modnamelen, true); + /* Handle all-NULL symbols allocated into .bss */ if (info->sechdrs[get_secindex(info, sym)].sh_type & SHT_NOBITS) { zeros = calloc(1, sym->st_size); diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index be89921d60b6..f39e3456e021 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -168,9 +168,12 @@ char *get_line(char **stringp) return orig; } -/* A list of all modules we processed */ +/* A list of all modules (vmlinux or *.ko) we processed */ LIST_HEAD(modules); +/* A list of all builtin modules we processed */ +LIST_HEAD(builtin_modules); + static struct module *find_module(const char *filename, const char *modname) { struct module *mod; @@ -183,7 +186,7 @@ static struct module *find_module(const char *filename, const char *modname) return NULL; } -static struct module *new_module(const char *name, size_t namelen) +struct module *new_module(const char *name, size_t namelen, bool is_builtin) { struct module *mod; @@ -207,7 +210,10 @@ static struct module *new_module(const char *name, size_t namelen) */ mod->is_gpl_compatible = true; - list_add_tail(&mod->list, &modules); + if (is_builtin) + list_add_tail(&mod->list, &builtin_modules); + else + list_add_tail(&mod->list, &modules); return mod; } @@ -1573,7 +1579,7 @@ static void read_symbols(const char *modname) } /* strip trailing .o */ - mod = new_module(modname, strlen(modname) - strlen(".o")); + mod = new_module(modname, strlen(modname) - strlen(".o"), false); /* save .no_trim_symbol section for later use */ if (info.no_trim_symbol_len) { @@ -2021,11 +2027,23 @@ static void write_if_changed(struct buffer *b, const char *fname) static void write_vmlinux_export_c_file(struct module *mod) { struct buffer buf = { }; + struct module_alias *alias, *next; buf_printf(&buf, - "#include <linux/export-internal.h>\n"); + "#include <linux/export-internal.h>\n" + "#include <linux/module.h>\n"); add_exported_symbols(&buf, mod); + + list_for_each_entry(mod, &builtin_modules, list) { + list_for_each_entry_safe(alias, next, &mod->aliases, node) { + buf_printf(&buf, "MODULE_ALIAS_MODNAME(\"%s\", \"%s\");\n", + mod->name, alias->str); + list_del(&alias->node); + free(alias); + } + } + write_if_changed(&buf, ".vmlinux.export.c"); free(buf.p); } @@ -2114,7 +2132,7 @@ static void read_dump(const char *fname) mod = find_module(fname, modname); if (!mod) { - mod = new_module(modname, strlen(modname)); + mod = new_module(modname, strlen(modname), false); mod->dump_file = fname; } s = sym_add_exported(symname, mod, gpl_only, namespace); diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 9133e4c3803f..f2b6d25f00ff 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -107,7 +107,7 @@ struct module_alias { }; /** - * struct module - represent a module (vmlinux or *.ko) + * struct module - represent a module (vmlinux, a builtin module, or *.ko) * * @dump_file: path to the .symvers file if loaded from a file * @aliases: list head for module_aliases @@ -199,6 +199,8 @@ static inline bool is_valid_name(struct elf_info *elf, Elf_Sym *sym) return !is_mapping_symbol(name); } +struct module *new_module(const char *name, size_t namelen, bool is_builtin); + /* symsearch.c */ void symsearch_init(struct elf_info *elf); void symsearch_finish(struct elf_info *elf); -- Cheers, Petr