On Tue, Dec 20, 2022 at 12:45 AM Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > On Mon, Dec 19, 2022 at 02:46:13PM -0600, Allen Webb wrote: > > Implement MODULE_DEVICE_TABLE for build-in modules to make it possible > > to generate a builtin.alias file to complement modules.alias. > > > > Signed-off-by: Allen Webb <allenwebb@xxxxxxxxxx> > > --- > > include/linux/module.h | 15 ++++++++++++++- > > 1 file changed, 14 insertions(+), 1 deletion(-) > > > > diff --git a/include/linux/module.h b/include/linux/module.h > > index ec61fb53979a..3d1b04ca6350 100644 > > --- a/include/linux/module.h > > +++ b/include/linux/module.h > > @@ -243,7 +243,20 @@ extern void cleanup_module(void); > > extern typeof(name) __mod_##type##__##name##_device_table \ > > __attribute__ ((unused, alias(__stringify(name)))) > > #else /* !MODULE */ > > -#define MODULE_DEVICE_TABLE(type, name) > > +/* > > + * The names may not be unique for built-in modules, so include the module name > > + * to guarantee uniqueness. > > What "names" are you referring to here with the words, "The names"? > > And built-in modules have the same rules as external names, they have to > be unique so I do not understand the problem you are trying to solve > here, which means you need to describe it better in both the changelog > text and the comment. I changed the comment to: /* * Creates an alias so file2alias.c can find device table for built in modules. * * The module name is included for two reasons: * - Adding the module name to the alias avoids creating two aliases with the * same name. Historically MODULE_DEVICE_TABLE was a no-op for built-in * modules, so there was nothing to stop different modules from having the * same device table name and consequently the same alias when building as a * module. * - The module name is needed by files2alias.c to associate a particular * device table with its associated module since files2alias would otherwise * see the module name as `vmlinuz.o` for built-in modules. */ > > > + * > > + * Note that extern is needed because modpost reads these symbols to generate > > + * modalias entries for each match id in each device table. They are not used > > + * at runtime. > > This comment isn't explaining much about what the #define is to be used > for, is it? I will drop this. I originally added the comment because Christophe Leroy said: "'extern' keyword is pointless of function prototypes and deprecated. Don't add new occurences." This is clearly not a typical function prototype and the guidance from: https://www.kernel.org/doc/html/latest/process/coding-style.html#function-prototypes should not apply. > > confused, > > greg k-h
