staging: ozwpan: kobject_uevent_env() from process context

Call kobject_uevent_env() always from process context.

Bug 1523226

Reviewed-on: http://git-master/r/425002
(cherry picked from commit a7168d798724a3049f6dc53cd0f35d2c34163e48)

Change-Id: I65e52eda1349b2a807c323d3f8768e1bda516a45
Signed-off-by: S Tateno <shigekatsu.tateno@atmel.com>
Signed-off-by: Vinayak Pane <vpane@nvidia.com>
Reviewed-on: http://git-master/r/426903
(cherry picked from commit aa608de59a483a9e868bb77b0e9460ec0eb551d6)
Reviewed-on: http://git-master/r/435716
GVS: Gerrit_Virtual_Submit
Reviewed-by: Anshul Jain (SW) <anshulj@nvidia.com>
Tested-by: Anshul Jain (SW) <anshulj@nvidia.com>

3 files changed, 35 insertions, 16 deletions

diff --git a/drivers/staging/ozwpan/ozpd.c b/drivers/staging/ozwpan/ozpd.c
index ad4acb59e8d9..def50af78132 100644
--- a/drivers/staging/ozwpan/ozpd.c
+++ b/drivers/staging/ozwpan/ozpd.c
@@ -268,8 +268,38 @@ void oz_pd_destroy(struct oz_pd *pd)
 	memset(&pd->workitem, 0, sizeof(pd->workitem));
 	INIT_WORK(&pd->workitem, oz_pd_free);
 	ret = schedule_work(&pd->workitem);
+	if (!ret)
+		pr_info("failed to schedule workitem\n");
+}
+/*------------------------------------------------------------------------------
+ */
+static void oz_pd_uevent_workitem(struct work_struct *work)
+{
+	struct oz_pd *pd;
+	char mac_buf[20];
+	char *envp[2];
 
-	if (ret)
+	pd = container_of(work, struct oz_pd, uevent_workitem);
+
+	oz_trace_msg(D, "uevent ID_MAC:%pm\n", pd->mac_addr);
+	snprintf(mac_buf, sizeof(mac_buf), "ID_MAC=%pm", pd->mac_addr);
+	envp[0] = mac_buf;
+	envp[1] = NULL;
+	kobject_uevent_env(&g_oz_wpan_dev->kobj, KOBJ_CHANGE, envp);
+	oz_pd_put(pd);
+}
+/*------------------------------------------------------------------------------
+ */
+void oz_pd_notify_uevent(struct oz_pd *pd)
+{
+	int ret;
+
+	oz_pd_get(pd);
+	memset(&pd->uevent_workitem, 0, sizeof(pd->uevent_workitem));
+	INIT_WORK(&pd->uevent_workitem, oz_pd_uevent_workitem);
+	ret = schedule_work(&pd->uevent_workitem);
+
+	if (!ret)
 		oz_trace("failed to schedule workitem\n");
 }
 
@@ -374,12 +404,6 @@ int oz_pd_sleep(struct oz_pd *pd)
 {
 	int do_stop = 0;
 	u16 stop_apps = 0;
-	char mac_buf[20];
-	char *envp[2];
-
-	snprintf(mac_buf, sizeof(mac_buf), "ID_MAC=%pm", pd->mac_addr);
-	envp[0] = mac_buf;
-	envp[1] = NULL;
 	oz_polling_lock_bh();
 	if (pd->state & (OZ_PD_S_SLEEP | OZ_PD_S_STOPPED)) {
 		oz_polling_unlock_bh();
@@ -389,7 +413,7 @@ int oz_pd_sleep(struct oz_pd *pd)
 		if (pd->keep_alive >= OZ_KALIVE_INFINITE)
 			oz_pd_indicate_farewells(pd);
 		oz_pd_set_state(pd, OZ_PD_S_SLEEP);
-		kobject_uevent_env(&g_oz_wpan_dev->kobj, KOBJ_CHANGE, envp);
+		oz_pd_notify_uevent(pd);
 	} else {
 		do_stop = 1;
 	}
diff --git a/drivers/staging/ozwpan/ozpd.h b/drivers/staging/ozwpan/ozpd.h
index a4270fe69ee5..5f5e7241ff47 100644
--- a/drivers/staging/ozwpan/ozpd.h
+++ b/drivers/staging/ozwpan/ozpd.h
@@ -109,6 +109,7 @@ struct oz_pd {
 	struct tasklet_struct	timeout_tasklet;
 	unsigned long tasklet_sched;
 	struct work_struct workitem;
+	struct work_struct uevent_workitem;
 	u8	up_audio_buf;
 };
 
@@ -134,5 +135,6 @@ int oz_send_isoc_unit(struct oz_pd *pd, u8 ep_num, const u8 *data, int len);
 void oz_handle_app_elt(struct oz_pd *pd, u8 app_id, struct oz_elt *elt);
 void oz_apps_init(void);
 void oz_apps_term(void);
+void oz_pd_notify_uevent(struct oz_pd *pd);
 
 #endif /* Sentry */
diff --git a/drivers/staging/ozwpan/ozproto.c b/drivers/staging/ozwpan/ozproto.c
index 1066c4e49ad7..a9eea6e0692d 100644
--- a/drivers/staging/ozwpan/ozproto.c
+++ b/drivers/staging/ozwpan/ozproto.c
@@ -352,15 +352,8 @@ static void oz_rx_frame(struct sk_buff *skb)
 	pd = oz_pd_find(src_addr);
 	if (pd) {
 		if (!(pd->state & OZ_PD_S_CONNECTED)) {
-			char mac_buf[20];
-			char *envp[2];
-			snprintf(mac_buf, sizeof(mac_buf), "ID_MAC=%pm",
-								pd->mac_addr);
-			envp[0] = mac_buf;
-			envp[1] = NULL;
 			oz_pd_set_state(pd, OZ_PD_S_CONNECTED);
-			kobject_uevent_env(&g_oz_wpan_dev->kobj, KOBJ_CHANGE,
-									envp);
+			oz_pd_notify_uevent(pd);
 		}
 		getnstimeofday(&current_time);
 		if ((current_time.tv_sec != pd->last_rx_timestamp.tv_sec) ||