[Bug 220069] [6.13.9] regression USB controller dies

[bugzilla-daemon@kernel.org]

https://bugzilla.kernel.org/show_bug.cgi?id=220069

--- Comment #42 from Mathias Nyman (mathias.nyman@linux.intel.com) ---

The two Reset Device commands followed by an Address Device command
that Michal pointed out earlier could very well be the reason for the issue.

Reset Device Command: slot 16 flags C
Reset Device Command: slot 19 flags C
Reset Device Command: slot 19 flags C
Address Device Command: ctx 00000000fff42000 slot 19 flags b:C

A Reset Device command will move the slot (device) to the Default address 0
state where only one device should be at a time. In default state the device
waits for a address device commands to be given a unique address.

Here we have both slots 16 and 19 in default state at the same time, and both
devices will try to respond to the address device command.

Xhci section 4.5.3.4 "Default" has a note stating that: 
"Software shall ensure that only one Device Slot is in the Default state at
time,otherwise undefined behavior may occur."

The commit 2b66ef84d0d2 "usb: hub: lack of clearing xHC resource" that Michal
pointed out earlier looks like possible cause to me as well.

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