On 22.11.2021 17.41, Hans de Goede wrote:

Hi,

On 11/22/21 11:50, Mathias Nyman wrote:

quoted

Fix the circular lock dependency and unbalanced unlock of addess0_mutex
introduced when fixing an address0_mutex enumeration retry race in commit
ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0 race")

Make sure locking order between port_dev->status_lock and address0_mutex
is correct, and that address0_mutex is not unlocked in hub_port_connect
"done:" codepath which may be reached without locking address0_mutex

Fixes: 6ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0 race")
Cc: <redacted>
Signed-off-by: Mathias Nyman <redacted>

Oh, this is great, with this patch I can finally hot-plug my
thunderbolt dock (and thus a XHCI controller) without the XHCI
controller given a whole bunch of weird errors (and some USB
devices not working), which it does not when already connected at boot.

I also tried the hotplug thingy with the previous fix without
this locking fix and then I actually hit the deadlock and things
like lsusb would hang.

If we can get these 2 fixes together merged soon and also backported
to the stable series that would be great:

Acked-by: Hans de Goede <redacted>
Tested-by: Hans de Goede <redacted>

Regards,

Hans

Thanks for testing, I'll add your tags and submit this.

-Mathias