CHROMEOS: ath9k: fix power save race conditions

chromeos/compat-wireless/drivers/net/wireless/ath/ath9k/recv.c

 /*
  * Copyright (c) 2008-2009 Atheros Communications Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
@@ skipping 1081 matching lines @@
         struct ieee80211_hdr *hdr;
         int retval;
         bool decrypt_error = false;
         struct ath_rx_status rs;
         enum ath9k_rx_qtype qtype;
         bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
         int dma_type;
         u8 rx_status_len = ah->caps.rx_status_len;
         u64 tsf = 0;
         u32 tsf_lower = 0;
+        unsigned long flags;
 
         if (edma)
                 dma_type = DMA_BIDIRECTIONAL;
         else
                 dma_type = DMA_FROM_DEVICE;
 
         qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
         spin_lock_bh(&sc->rx.rxbuflock);
 
         tsf = ath9k_hw_gettsf64(ah);
@@ skipping 88 matching lines @@
                  * change the default rx antenna if rx diversity chooses the
                  * other antenna 3 times in a row.
                  */
                 if (sc->rx.defant != rs.rs_antenna) {
                         if (++sc->rx.rxotherant >= 3)
                                 ath_setdefantenna(sc, rs.rs_antenna);
                 } else {
                         sc->rx.rxotherant = 0;
                 }
 
+                spin_lock_irqsave(&sc->sc_pm_lock, flags);
                 if (unlikely(ath9k_check_auto_sleep(sc) ||
                              (sc->ps_flags & (PS_WAIT_FOR_BEACON |
                                               PS_WAIT_FOR_CAB |
                                               PS_WAIT_FOR_PSPOLL_DATA))))
                         ath_rx_ps(sc, skb);
+                spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 
                 ath_rx_send_to_mac80211(hw, sc, skb, rxs);
 
 requeue:
                 if (edma) {
                         list_add_tail(&bf->list, &sc->rx.rxbuf);
                         ath_rx_edma_buf_link(sc, qtype);
                 } else {
                         list_move_tail(&bf->list, &sc->rx.rxbuf);
                         ath_rx_buf_link(sc, bf);
                 }
         } while (1);
 
         spin_unlock_bh(&sc->rx.rxbuflock);
 
         return 0;
 }