iwlagn: avoid sleep in softirq context

__ieee80211_tasklet_handler -> __ieee80211_rx ->
	__ieee80211_rx_handle_packet -> ieee80211_invoke_rx_handlers ->
	ieee80211_rx_h_decrypt -> ieee80211_crypto_tkip_decrypt ->
	ieee80211_tkip_decrypt_data -> iwl4965_mac_update_tkip_key ->
	iwl_scan_cancel_timeout -> msleep

Ooops!

Avoid the sleep by changing iwl_scan_cancel_timeout with
iwl_scan_cancel and simply returning on failure if the scan persists.
This will cause hardware decryption to fail and we'll handle a few more
frames with software decryption.

Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 321dbc8c034a9d608fff552fc90cafc3c1480777..8d690a0eb1a967722508942d9fdd90225c98be47 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -3252,7 +3252,11 @@ static void iwl4965_mac_update_tkip_key(struct ieee80211_hw *hw,
                return;
        }
 
-       iwl_scan_cancel_timeout(priv, 100);
+       if (iwl_scan_cancel(priv)) {
+               /* cancel scan failed, just live w/ bad key and rely
+                  briefly on SW decryption */
+               return;
+       }
 
        key_flags |= (STA_KEY_FLG_TKIP | STA_KEY_FLG_MAP_KEY_MSK);
        key_flags |= cpu_to_le16(keyconf->keyidx << STA_KEY_FLG_KEYID_POS);