I triggerd the BUG_ON() in driver_register(), which was added in f48f3febb2cbfd0f2ecee7690835ba745c1034a4, when booting a domU Xen domain. Since there was no contextual information logged, I needed to attach kgdb to determine the culprit (the wmi-bmof driver in my case).
Instead of running into a BUG_ON() we print an error message identifying the driver but continue booting. Signed-off-by: Florian Schmaus <f...@geekplace.eu> --- drivers/base/driver.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/base/driver.c b/drivers/base/driver.c index ba912558a510..63baec586eba 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -148,7 +148,11 @@ int driver_register(struct device_driver *drv) int ret; struct device_driver *other; - BUG_ON(!drv->bus->p); + if (!drv->bus->p) { + printk(KERN_ERR "Driver '%s' was unable to register bus_type\n", + drv->name); + return -EBUSY; + } if ((drv->bus->probe && drv->probe) || (drv->bus->remove && drv->remove) || -- 2.16.1