On Saturday, July 20, 2013 05:06:29 AM Rafael J. Wysocki wrote: > On Saturday, July 20, 2013 02:00:44 AM Rafael J. Wysocki wrote: > > On Friday, July 19, 2013 04:16:30 PM Greg Kroah-Hartman wrote: > > > On Fri, Jul 19, 2013 at 11:38:04PM +0200, Rafael J. Wysocki wrote: > > > > Alas, this is not the one I'd like to apply. > > > > > > > > With that patch applied, new device objects are created to avoid binding the > > > > processor driver directly to the cpu system device objects, because that > > > > apparently confuses udev and it starts to ignore the cpu modalias once the > > > > driver has been bound to any of those objects. > > > > > > > > I've verified in the meantime that this indeed is the case. > > > > > > > > A link to the patch in question: https://patchwork.kernel.org/patch/2830561/ > > > > > > > > Greg, I asked you some time ago whether or not it was possible for udev to stop > > > > autoloading modules that matched the cpu modalias after a driver had been bound > > > > to the cpu system device objects and you said "no". However, this time I can > > > > say with certainty that that really is the case. So, the question now is > > > > whether or not we can do anything in the kernel to avoid that confusion in udev > > > > instead of applying the patch linked above (which is beyond ugly in my not so > > > > humble opinion)? > > > > > > udev isn't doing any module loading, 'modprobe' is just being called for > > > any new module alias that shows up in the system, and all of the drivers > > > that match it then get loaded. > > > > The problem is that that doesn't happen when a driver is bound to the > > cpu system device objects. modprobe is just not called for modules that > > match the cpu modalias in that case. > > > > If I call modprobe manually for any of the modules in question, it loads > > and works no problem. > > OK, I know what's up. udev has no rule that would allow it to load stuff on > the basis of MODALIAS if DRIVER is set in the event properties. > > So, the following rule needs to be added to udev rules for things to work > as before: > > DRIVER=="processor", ENV{MODALIAS}=="?*", IMPORT{builtin}="kmod load $env{MODALIAS}" > > To be precise, I added a file called 80-drivers.rules to /etc/udev/rules.d/ Well, that wasn't a good idea, because the original 80-drivers.rules didn't work then, but I renamed the new file (in /etc/udev/rules.d/) to 80-cpu.rules and put this line (alone) into it: ACTION="add", SUBSYSTEM=="cpu", ENV{MODALIAS}=="?*", IMPORT{builtin}="kmod load $env{MODALIAS}" After that change everything works happily again. Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
