commit dd4dd08b2c87f226777d7725b8c599641504988e
author Rajeev Kumar <rajekuma@codeaurora.org> Thu Feb 25 12:24:32 2016 -0800
committer Gerrit - the friendly Code Review server <code-review@localhost> Sun Apr 17 18:00:21 2016 -0700
tree 3ad5cb1ab9c0a4cf8f72dee8035ec316cc79f8cd
parent 7e16b0a68f55038df67045bfb7d1bda9e5bf83f1

qcacld-3.0: Fix deadlock in hdd_adapter_lock usage

hdd_adapter_lock is acquired from MC thread and hif_napi soft IRQ
context so it should be acquired using spin_lock_bh such that when
MC thread is holding the lock soft IRQ can't pre-empt it and lead
to deadlock

Change-Id: Iee4a4905bf7cc09cba9bd26f416d505eb47a5c96
CRs-Fixed: 981886

core/hdd/src/wlan_hdd_main.c

diff --git a/core/hdd/src/wlan_hdd_main.c b/core/hdd/src/wlan_hdd_main.c
index 79b5273..2c954e3 100644
--- a/core/hdd/src/wlan_hdd_main.c
+++ b/core/hdd/src/wlan_hdd_main.c
@@ -3272,10 +3272,10 @@
 				 hdd_adapter_list_node_t **padapterNode)
 {
 	QDF_STATUS status;
-	qdf_spin_lock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_lock_bh(&hdd_ctx->hdd_adapter_lock);
 	status = qdf_list_peek_front(&hdd_ctx->hddAdapters,
 				     (qdf_list_node_t **) padapterNode);
-	qdf_spin_unlock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_unlock_bh(&hdd_ctx->hdd_adapter_lock);
 	return status;
 }
 
@@ -3284,12 +3284,12 @@
 				hdd_adapter_list_node_t **pNextAdapterNode)
 {
 	QDF_STATUS status;
-	qdf_spin_lock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_lock_bh(&hdd_ctx->hdd_adapter_lock);
 	status = qdf_list_peek_next(&hdd_ctx->hddAdapters,
 				    (qdf_list_node_t *) adapterNode,
 				    (qdf_list_node_t **) pNextAdapterNode);
 
-	qdf_spin_unlock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_unlock_bh(&hdd_ctx->hdd_adapter_lock);
 	return status;
 }
 
@@ -3297,10 +3297,10 @@
 			      hdd_adapter_list_node_t *adapterNode)
 {
 	QDF_STATUS status;
-	qdf_spin_lock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_lock_bh(&hdd_ctx->hdd_adapter_lock);
 	status = qdf_list_remove_node(&hdd_ctx->hddAdapters,
 				      &adapterNode->node);
-	qdf_spin_unlock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_unlock_bh(&hdd_ctx->hdd_adapter_lock);
 	return status;
 }
 
@@ -3308,10 +3308,10 @@
 				    hdd_adapter_list_node_t **padapterNode)
 {
 	QDF_STATUS status;
-	qdf_spin_lock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_lock_bh(&hdd_ctx->hdd_adapter_lock);
 	status = qdf_list_remove_front(&hdd_ctx->hddAdapters,
 				       (qdf_list_node_t **) padapterNode);
-	qdf_spin_unlock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_unlock_bh(&hdd_ctx->hdd_adapter_lock);
 	return status;
 }
 
@@ -3319,10 +3319,10 @@
 				hdd_adapter_list_node_t *adapterNode)
 {
 	QDF_STATUS status;
-	qdf_spin_lock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_lock_bh(&hdd_ctx->hdd_adapter_lock);
 	status = qdf_list_insert_back(&hdd_ctx->hddAdapters,
 				      (qdf_list_node_t *) adapterNode);
-	qdf_spin_unlock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_unlock_bh(&hdd_ctx->hdd_adapter_lock);
 	return status;
 }
 
@@ -3330,10 +3330,10 @@
 				 hdd_adapter_list_node_t *adapterNode)
 {
 	QDF_STATUS status;
-	qdf_spin_lock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_lock_bh(&hdd_ctx->hdd_adapter_lock);
 	status = qdf_list_insert_front(&hdd_ctx->hddAdapters,
 				       (qdf_list_node_t *) adapterNode);
-	qdf_spin_unlock(&hdd_ctx->hdd_adapter_lock);
+	qdf_spin_unlock_bh(&hdd_ctx->hdd_adapter_lock);
 	return status;
 }