mwifiex: fix hang issue for USB chipsets

Bug 60815 - Interface hangs in mwifiex_usb
https://bugzilla.kernel.org/show_bug.cgi?id=60815

We have 4 bytes of interface header for packets delivered to SDIO
and PCIe, but not for USB interface.

In Tx AMSDU case, currently 4 bytes of garbage data is unnecessarily
appended for USB packets. This sometimes leads to a firmware hang,
because it may not interpret the data packet correctly.

Problem is fixed by removing this redundant headroom for USB.

Cc: <stable@vger.kernel.org> # 3.5+
Tested-by: Dmitry Khromov <icechrome@gmail.com>
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 4 insertions, 4 deletions

diff --git a/drivers/net/wireless/mwifiex/11n_aggr.c b/drivers/net/wireless/mwifiex/11n_aggr.c
index 21c688264708..1214c587fd08 100644
--- a/drivers/net/wireless/mwifiex/11n_aggr.c
+++ b/drivers/net/wireless/mwifiex/11n_aggr.c
@@ -150,7 +150,7 @@ mwifiex_11n_form_amsdu_txpd(struct mwifiex_private *priv,
  */
 int
 mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
-                          struct mwifiex_ra_list_tbl *pra_list, int headroom,
+                          struct mwifiex_ra_list_tbl *pra_list,
                           int ptrindex, unsigned long ra_list_flags)
                           __releases(&priv->wmm.ra_list_spinlock)
 {
@@ -160,6 +160,7 @@ mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
         int pad = 0, ret;
         struct mwifiex_tx_param tx_param;
         struct txpd *ptx_pd = NULL;
+        int headroom = adapter->iface_type == MWIFIEX_USB ? 0 : INTF_HEADER_LEN;
 
         skb_src = skb_peek(&pra_list->skb_head);
         if (!skb_src) {
diff --git a/drivers/net/wireless/mwifiex/11n_aggr.h b/drivers/net/wireless/mwifiex/11n_aggr.h
index 900e1c62a0cc..892098d6a696 100644
--- a/drivers/net/wireless/mwifiex/11n_aggr.h
+++ b/drivers/net/wireless/mwifiex/11n_aggr.h
@@ -26,7 +26,7 @@
 int mwifiex_11n_deaggregate_pkt(struct mwifiex_private *priv,
                                 struct sk_buff *skb);
 int mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
-                              struct mwifiex_ra_list_tbl *ptr, int headroom,
+                              struct mwifiex_ra_list_tbl *ptr,
                               int ptr_index, unsigned long flags)
                               __releases(&priv->wmm.ra_list_spinlock);
 
diff --git a/drivers/net/wireless/mwifiex/wmm.c b/drivers/net/wireless/mwifiex/wmm.c
index 2e8f9cdea54d..95fa3599b407 100644
--- a/drivers/net/wireless/mwifiex/wmm.c
+++ b/drivers/net/wireless/mwifiex/wmm.c
@@ -1239,8 +1239,7 @@ mwifiex_dequeue_tx_packet(struct mwifiex_adapter *adapter)
                 if (enable_tx_amsdu && mwifiex_is_amsdu_allowed(priv, tid) &&
                     mwifiex_is_11n_aggragation_possible(priv, ptr,
                                                         adapter->tx_buf_size))
-                        mwifiex_11n_aggregate_pkt(priv, ptr, INTF_HEADER_LEN,
-                                                  ptr_index, flags);
+                        mwifiex_11n_aggregate_pkt(priv, ptr, ptr_index, flags);
                         /* ra_list_spinlock has been freed in
                            mwifiex_11n_aggregate_pkt() */
                 else