On Wed, 2010-06-02 at 23:01 +0200, Coelho Luciano (Nokia-D/Helsinki) wrote: > On Wed, 2010-06-02 at 22:04 +0200, Coelho Luciano (Nokia-D/Helsinki) > wrote: > > What causes printk to appear under /sys/module even when compiled in, is > > that it uses a module param. This line: > > > > module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR); > > > > ...is what triggers the printk directory to be created in sysfs. If I > > add a similar line in my module, it shows up there too. > > > > I still don't know if there is an actual kobject associated with it, > > I'll check that next. > > Okay, so here is how it goes: if the module is linked into the kernel > and it has module parameters, the kernel creates a kobj for it as a > module_ktype without parent, which will cause it to show up > in /sys/modules. > > I could do the same in the module initialization when THIS_MODULE == > NULL, but I don't see any other module doing this. In fact, I only see > the kernel itself creating kobjects of module_ktype (in load_module() > and in the case I just described). Smells like a terrible hack to do > that in the module itself... :( > > Adding bogus parameters to the module just to trig the kernel to create > the kobject also seems to be too hacky... Looking closer, it seems that it makes a bit of sense to add a kernel module to /sys/device/system. I think it makes more sense than adding to the module class or to the net class, actually. The idletimer is not a net device (so it doesn't fit in /sys/class/net) and it is not a module, even though it may be handled by the xt_IDLETIMER module. So we can look at the xt_idletimer as a system device, which is not a peripheral device in itself, but a software timer device (there are already similar components). I'll add the kernel object we need as a system class device, so it will go under /sys/devices/system/xt_idletimer. Does that make sense to you? -- Cheers, Luca. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
