On Sun, Sep 14, 2014 at 10:05:46PM +0400, Kirill Tkhai wrote: > On 14.09.2014 21:39, Greg KH wrote: > > On Sun, Sep 14, 2014 at 09:31:58PM +0400, Kirill Tkhai wrote: > >> On 14.09.2014 19:38, Greg KH wrote: > >>> On Sun, Sep 14, 2014 at 02:18:13PM +0400, Kirill Tkhai wrote: > >>>> This series implements a possibility to show the list of built-in drivers > >>>> to userspace. The names of drivers will be the same as when they are modules. > >>> > >>> Have you looked at /sys/modules/ ? Doesn't that show what you want > >>> here? > >> > >> There are only the drivers in "/sys/module" which have parameters. > >> Drivers without parameters do not appear there. > > > > Ah, didn't realize that. Should be easy to fix though, if you really > > wanted to list the modules. Much better than a random proc file that > > you have to parse :) > > But it looks like one file is better than many new directories. Why? > Furthermore some utils already may consider /sys/module directory as > a directory where all drivers have parameters. Is it good if we add > new ones of different type there? What would break if you add new directories there with no parameters? > >>>> So, if your system has "loop" driver then it appears either in /proc/modules > >>>> or in /proc/built-in and userspace will be able to know about this. > >>>> > >>>> Now this is impossible. The only way to get kernel configuration is > >>>> /proc/config.gz, but CONFIG_* names can change from time to time. Module > >>>> names are more or less standardized. > >>> > >>> Module names aren't "standardized", we change them at times when needed, > >>> just like CONFIG_ names. > >>> > >>> What is your end goal here? As you say, config.gz is the real kernel > >>> configuration, just having a list of modules built in isn't going to > >>> help much in getting a working kernel config without it. > >> > >> It looks like userspace applications oriented on modules names rather > >> than on CONFIG_XXX parameters. /proc/config.gz is optional and userspace > >> applications can't base on it. > >> > >> For example, when I compile "loop" module built-in and "loop" is in > >> /etc/modules, init script warns about this module is not present and > >> can't be autoloaded. The script does not store CONFIG_XXX <-> module_xxx > >> conformity. And nobody stores it. > >> > >> When iptables wants extra functionality, it requests a module. Etc. > >> > >> Nobody is oriented on CONFIG_XXX parameters. It would be simple for > >> userspace to add a support of /proc/built-in analysing. It's very > >> similar to /proc/modules. > > > > Shouldn't userspace focus on the functionality a module provides, not > > the module name itself? Can't a test for the loop "module" just test to > > see if the loop control device is present? Same for iptables (there's > > modprobe rules for iptable modules I think...) > > > > In other words, don't focus on the module names, focus on the userspace > > function a module provides, there should always be a way to check that > > at run time (if not, then the module doesn't actually do much...) > > Hm, I'm not sure that anybody stores CONFIG_XXX <-> module_xxx > conformity. Everybody bases on module name. If application is seeing > CONFIG_XXX=m, but the functionality, which it want's, is not available, > what it has to do? How should it convert CONFIG_XXX to module name? Why would an application ever care about CONFIG_XXX at runtime? > So, many applications want module name instead of CONFIG_XXX, I believe. No, they want the functionality that a module provides, not the module name, or some random configuation option. It seems like you are trying to solve a problem that isn't there. What program is broken right now that this new proc file (or sysfs directory) would fix? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
