On Wed, Jul 22, 2015 at 09:04:40PM -0500, Felipe Balbi wrote: > On Wed, Jul 22, 2015 at 02:39:34PM -0700, Greg Kroah-Hartman wrote: > > On Tue, Jun 23, 2015 at 01:57:38PM +0300, Heikki Krogerus wrote: > > > On Fri, Jun 19, 2015 at 01:12:36AM +0800, ChengYi He wrote: > > > > put_device is required to release the last reference to the device. > > > > > > > > Signed-off-by: ChengYi He <chengyihetaipei@xxxxxxxxx> > > > > --- > > > > drivers/usb/common/ulpi.c | 4 +++- > > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c > > > > index 0e6f968..bd25bdb 100644 > > > > --- a/drivers/usb/common/ulpi.c > > > > +++ b/drivers/usb/common/ulpi.c > > > > @@ -184,8 +184,10 @@ static int ulpi_register(struct device *dev, struct ulpi *ulpi) > > > > request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product); > > > > > > > > ret = device_register(&ulpi->dev); > > > > - if (ret) > > > > + if (ret) { > > > > + put_device(&ulpi->dev); > > > > > > If device_register returns failure, put_device has already been > > > called. Check device_add in drivers/base/core.c. > > > > Yes, please read the function, which says: > > * NOTE: _Never_ directly free @dev after calling this function, even > > * if it returned an error! Always use put_device() to give up your > > * reference instead. > > > > But, the problem is that the ulpi core doesn't "own" that struct device. > > It comes from elsewhere. It comes from somewhere deep down in the dw3 > > core, which is where I lost the path. Something needs to be fixed in > > dwc3_probe() to properly clean up the device if it fails, which is not > > happening right now. > > > > So this patch would actually cause much bigger problems than fixing > > anything, so it's wrong, but for a different reason than you are talking > > about here. > > > > And ugh, the ulpi and dwc code binding together, what a mess, horrid... > > any suggestions ? DWC *is* the one implementing the bus. If there's a > better way, we can certainly shuffle code around. As dwc is the only thing using the bus, why is it drivers/usb/core/ ? And the error path here is broken, the bus should be creating the device (i.e. no subsystem should ever be registering a device it did not create), so that it can properly clean things up when stuff goes wrong. The whole subsys_init() is also a bad feeling that it's not architected correctly, that shouldn't be needed, which is why I never took that patch. Just noticed it came in through yours, I wanted it "broken" so it would be fixed "properly" and not papered over like this. 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