[PATCH 12/17] iwlwifi: mvm: hold mutex when flushing in iwl_mvm_flush_no_vif()

[Luca Coelho]

From: Luca Coelho <luciano.coe...@intel.com>

The iwl_mvm_flush_tx_path() function sends a synchronous command to
the firmware.  When doing that, we must hold the mutex.  The
iwl_mvm_flush_no_vif() function was mistakenly not holding the mutex.
Fix it.

Fixes: 6110d9e5bdd1 ("iwlwifi: mvm: Flush non STA TX queues")
Signed-off-by: Luca Coelho <luciano.coe...@intel.com>
---
 drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c 
b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index ae2eb0c8cbeb..3e92a117c0b8 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -4005,11 +4005,14 @@ static void iwl_mvm_flush_no_vif(struct iwl_mvm *mvm, 
u32 queues, bool drop)
        int i;
 
        if (!iwl_mvm_has_new_tx_api(mvm)) {
-               if (drop)
+               if (drop) {
+                       mutex_lock(&mvm->mutex);
                        iwl_mvm_flush_tx_path(mvm,
                                iwl_mvm_flushable_queues(mvm) & queues, 0);
-               else
+                       mutex_unlock(&mvm->mutex);
+               } else {
                        iwl_trans_wait_tx_queues_empty(mvm->trans, queues);
+               }
                return;
        }
 
-- 
2.14.2