On Wed, May 27, 2015 at 08:21:16AM -0700, Greg KH wrote: > On Wed, May 27, 2015 at 11:16:34AM -0400, Alan Stern wrote: > > On Wed, 27 May 2015, Heikki Krogerus wrote: > > Maybe we need to test for this in the driver core, not allowing drivers > for busses that are not registered, that might solve the main problem > here. I'll try to look at it tonight. may i suggest something like this ? buildtest with allmodconfig and allyesconfig on x86_64. built and booted on x86. diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 5005924..95cefa0 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -943,6 +943,7 @@ int bus_register(struct bus_type *bus) if (retval) goto bus_groups_fail; + bus->registered = true; pr_debug("bus: '%s': registered\n", bus->name); return 0; diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 4eabfe2..1acae5b 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -150,6 +150,11 @@ int driver_register(struct device_driver *drv) int ret; struct device_driver *other; + if (!drv->bus->registered) { + pr_err("Driver %s registration failed. bus not yet registered\n", + drv->name); + return -ENODEV; + } BUG_ON(!drv->bus->p); if ((drv->bus->probe && drv->probe) || diff --git a/include/linux/device.h b/include/linux/device.h index 00ac57c..8fe4745 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -126,6 +126,7 @@ struct bus_type { const struct dev_pm_ops *pm; const struct iommu_ops *iommu_ops; + bool registered; /* DON'T TOUCH THIS */ struct subsys_private *p; struct lock_class_key lock_key; regards sudip > > thanks, > > greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html