thunderbolt: Do not double dequeue a configuration request

thunderbolt: Do not double dequeue a configuration request

commit 0f73628e9da1ee39daf5f188190cdbaee5e0c98c upstream.

Some of our devices crash in tb_cfg_request_dequeue():

 general protection fault, probably for non-canonical address 0xdead000000000122

 CPU: 6 PID: 91007 Comm: kworker/6:2 Tainted: G U W 6.6.65
 RIP: 0010:tb_cfg_request_dequeue+0x2d/0xa0
 Call Trace:
 <TASK>
 ? tb_cfg_request_dequeue+0x2d/0xa0
 tb_cfg_request_work+0x33/0x80
 worker_thread+0x386/0x8f0
 kthread+0xed/0x110
 ret_from_fork+0x38/0x50
 ret_from_fork_asm+0x1b/0x30

The circumstances are unclear, however, the theory is that
tb_cfg_request_work() can be scheduled twice for a request:
first time via frame.callback from ring_work() and second
time from tb_cfg_request().  Both times kworkers will execute
tb_cfg_request_dequeue(), which results in double list_del()
from the ctl->request_queue (the list poison deference hints
at it: 0xdead000000000122).

Do not dequeue requests that don't have TB_CFG_REQUEST_ACTIVE
bit set.

Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>