On Tue, Aug 09, 2022 at 04:31:04PM +0200, Bastien Nocera wrote: > On Tue, 2022-08-09 at 12:38 +0200, Greg Kroah-Hartman wrote: > > Now if you really really want to disable a device from under a user, > > without the file handle present, you can do that today, as root, by > > doing the 'unbind' hack through userspace and sysfs. It's so common > > that this seems to be how virtual device managers handle virtual > > machines, so it should be well tested by now. > > The only thing I know that works that way is usbip, and it requires > unbinding each of the interfaces: > > https://sourceforge.net/p/usbip/git-windows/ci/master/tree/trunk/userspace/src/bind-driver.c#l157 virtio devices also use the api from what I recall. > That means that, for example, revoking access to the raw USB device > that OpenRGB used to blink colours across a keyboard would disconnect > the keyboard from the HID device. No, you unbind the usbfs driver, not the hid driver. > Can you show me any other users of that "trick" that would keep the > "hid" keyboard driver working while access to the /dev/bus/usb/* device > node is revoked/closed/yanked/unbound? Try unbinding usbfs from the device instead. > And if you can't, I would appreciate some efforts being made trying to > understand the use case, along with the limitations we're working > against, so we can find a good solution to the problem, instead of > retreading discussion points. As you have not documented the use case well enough in these changelog entries for me to understand it, the fact that I brought up things you previously discussed seems to mean you didn't document it well enough here for it not to come up again :) thanks, greg k-h
