re: brcm80211: fmac: fix missing completion events issue

[Dan Carpenter <dan.carpenter@oracle.com>]

Hello Franky Lin,

The patch b948a85c1f26: "brcm80211: fmac: fix missing completion 
events issue" from Apr 23, 2012, leads to the following Smatch warning:
drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c:2650 
brcmf_sdbrcm_dpc_thread()
	 error: double unlock 'spin_lock:&bus->dpc_tl_lock'


  2631  
  2632                  spin_lock_irqsave(&bus->dpc_tl_lock, flags);
  2633                  list_for_each_safe(cur_hd, tmp_hd, &bus->dpc_tsklst) {
  2634                          spin_unlock_irqrestore(&bus->dpc_tl_lock, flags);
  2635  
  2636                          if (bus->sdiodev->bus_if->state == BRCMF_BUS_DOWN) {
  2637                                  /* after stopping the bus, exit thread */
  2638                                  brcmf_sdbrcm_bus_stop(bus->sdiodev->dev);
  2639                                  bus->dpc_tsk = NULL;
  2640                                  break;
                                        ^^^^^^
We are not holding the lock here.

  2641                          }
  2642  
  2643                          if (brcmf_sdbrcm_dpc(bus))
  2644                                  brcmf_sdbrcm_adddpctsk(bus);
  2645  
  2646                          spin_lock_irqsave(&bus->dpc_tl_lock, flags);
  2647                          list_del(cur_hd);
  2648                          kfree(cur_hd);
  2649                  }
  2650                  spin_unlock_irqrestore(&bus->dpc_tl_lock, flags);
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Double unlock.  Double IRQ restore.

regards,
dan carpenter