Re: [PATCH 1/1] usb: xhci: hold lock over xhci_abort_cmd_ring()

[Mathias Nyman <mathias.nyman@linux.intel.com>]

On 23.12.2016 08:46, Lu Baolu wrote:
> In command timer function, xhci_handle_command_timeout(), xhci->lock
> is unlocked before call into xhci_abort_cmd_ring(). This might cause
> race between the timer function and the event handler.
>
> The xhci_abort_cmd_ring() function sets the CMD_RING_ABORT bit in the
> command register and polling it until the setting takes effect. A stop
> command ring event might be handled between writing the abort bit and
> polling for it. The event handler will restart the command ring, which
> causes the failure of polling, and we ever believed that we failed to
> stop it.
>
> As a bonus, this also fixes some issues of calling functions without
> locking in xhci_handle_command_timeout().
>

Did the same thing, moved the unlock to cover also abort_cmd_ring(),

but this one takes care of locking the command ring cleanup as well
so I'll pick up this instead

-Mathias