Re: [regression] frozen usb mouse pointer at boot

[Dan Williams <dan.j.williams@intel.com>]

Greg Kroah-Hartman wrote:
[..]
> 
> This is odd.
> 
> Does the latest 6.10.y release also show this problem?
> 
> I can't duplicate this here, and it's the first I've heard of it (given
> that USB mice are pretty popular, I would suspect others would have hit
> it as well...)

Sorry for missing this earlier. One thought is that userspace has a
dependency on uevent_show() flushing device probing. In other words the
side effect of taking the device_lock() in uevent_show() is that udev
might enjoy some occasions where the reading the uevent flushes probing
before the udev rule runs. With this change, uevent_show() no longer
waits for any inflight probes to complete.

One idea to fix this problem is to create a special case sysfs attribute
type that takes the device_lock() before kernfs_get_active() to avoid
the deadlock on attribute teardown.

I'll take a look. Thanks for forwarding the report Thorsten!