[patch 02/22] iwlagn: avoid sleep in softirq context

From: Greg KH
Date: Sat Nov 15 2008 - 00:25:51 EST


2.6.27-stable review patch. If anyone has any objections, please let us know.

------------------

From: John W. Linville <linville@xxxxxxxxxxxxx>

commit 964d2777438bf7687324243d38ade538d9bbfe3c upstream.

__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@xxxxxxxxxxxxx>
Cc: Holger Macht <hmacht@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/net/wireless/iwlwifi/iwl-agn.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -3275,7 +3275,11 @@ static void iwl4965_mac_update_tkip_key(
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);

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