iwpm: crash fix for large connections test

During large connection test, there is a crash at wake_up() in the callback as waitq is
not yet initialized. Callback can happen before iwpm_wait_complete_req() is called to
initialize waitq.
To resolve, using signaling semaphore instead of waitq.

Signed-off-by: Mustafa Ismail <mustafa.ismail@intel.com>
Reviewed-by: Tatyana E Nikolova <tatyana.e.nikolova@intel.com>
Signed-off-by: Faisal Latif <faisal.latif@intel.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

3 files changed, 13 insertions, 13 deletions

diff --git a/drivers/infiniband/core/iwpm_msg.c b/drivers/infiniband/core/iwpm_msg.c
index c2b4ce67fd4a..43e3fa27102b 100644
--- a/drivers/infiniband/core/iwpm_msg.c
+++ b/drivers/infiniband/core/iwpm_msg.c
@@ -89,7 +89,7 @@ int iwpm_register_pid(struct iwpm_dev_data *pm_msg, u8 nl_client)
         if (ret)
                 goto pid_query_error;
         ret = ibnl_put_attr(skb, nlh, IFNAMSIZ,
-                                pm_msg->if_name, IWPM_NLA_REG_IF_NAME);
+                            pm_msg->if_name, IWPM_NLA_REG_IF_NAME);
         if (ret)
                 goto pid_query_error;
         ret = ibnl_put_attr(skb, nlh, IWPM_DEVNAME_SIZE,
@@ -394,7 +394,7 @@ register_pid_response_exit:
         /* always for found nlmsg_request */
         kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
         barrier();
-        wake_up(&nlmsg_request->waitq);
+        up(&nlmsg_request->sem);
         return 0;
 }
 EXPORT_SYMBOL(iwpm_register_pid_cb);
@@ -463,7 +463,7 @@ add_mapping_response_exit:
         /* always for found request */
         kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
         barrier();
-        wake_up(&nlmsg_request->waitq);
+        up(&nlmsg_request->sem);
         return 0;
 }
 EXPORT_SYMBOL(iwpm_add_mapping_cb);
@@ -555,7 +555,7 @@ query_mapping_response_exit:
         /* always for found request */
         kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
         barrier();
-        wake_up(&nlmsg_request->waitq);
+        up(&nlmsg_request->sem);
         return 0;
 }
 EXPORT_SYMBOL(iwpm_add_and_query_mapping_cb);
@@ -749,7 +749,7 @@ int iwpm_mapping_error_cb(struct sk_buff *skb, struct netlink_callback *cb)
         /* always for found request */
         kref_put(&nlmsg_request->kref, iwpm_free_nlmsg_request);
         barrier();
-        wake_up(&nlmsg_request->waitq);
+        up(&nlmsg_request->sem);
         return 0;
 }
 EXPORT_SYMBOL(iwpm_mapping_error_cb);
diff --git a/drivers/infiniband/core/iwpm_util.c b/drivers/infiniband/core/iwpm_util.c
index 5fb089e91353..9b2bf2fb2b00 100644
--- a/drivers/infiniband/core/iwpm_util.c
+++ b/drivers/infiniband/core/iwpm_util.c
@@ -254,9 +254,9 @@ void iwpm_add_remote_info(struct iwpm_remote_info *rem_info)
 }
 
 int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
-                                struct sockaddr_storage *mapped_rem_addr,
-                                struct sockaddr_storage *remote_addr,
-                                u8 nl_client)
+                         struct sockaddr_storage *mapped_rem_addr,
+                         struct sockaddr_storage *remote_addr,
+                         u8 nl_client)
 {
         struct hlist_node *tmp_hlist_node;
         struct hlist_head *hash_bucket_head;
@@ -322,6 +322,8 @@ struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
         nlmsg_request->nl_client = nl_client;
         nlmsg_request->request_done = 0;
         nlmsg_request->err_code = 0;
+        sema_init(&nlmsg_request->sem, 1);
+        down(&nlmsg_request->sem);
         return nlmsg_request;
 }
 
@@ -364,11 +366,9 @@ struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq)
 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request)
 {
         int ret;
-        init_waitqueue_head(&nlmsg_request->waitq);
 
-        ret = wait_event_timeout(nlmsg_request->waitq,
-                        (nlmsg_request->request_done != 0), IWPM_NL_TIMEOUT);
-        if (!ret) {
+        ret = down_timeout(&nlmsg_request->sem, IWPM_NL_TIMEOUT);
+        if (ret) {
                 ret = -EINVAL;
                 pr_info("%s: Timeout %d sec for netlink request (seq = %u)\n",
                         __func__, (IWPM_NL_TIMEOUT/HZ), nlmsg_request->nlmsg_seq);
diff --git a/drivers/infiniband/core/iwpm_util.h b/drivers/infiniband/core/iwpm_util.h
index b7b9e194ce81..af1fc14a0d3d 100644
--- a/drivers/infiniband/core/iwpm_util.h
+++ b/drivers/infiniband/core/iwpm_util.h
@@ -69,7 +69,7 @@ struct iwpm_nlmsg_request {
         u8                  nl_client;
         u8                  request_done;
         u16                 err_code;
-        wait_queue_head_t   waitq;
+        struct semaphore    sem;
         struct kref         kref;
 };