[dpdk-dev] [PATCH] net/kni: fix crash caused by double stop

[Ferruh Yigit <ferruh.yigit@intel.com>]

'close()' calls 'stop()' and 'stop()' cancels pthread without any check.
Calling 'stop()' & 'close()' sequentially tries to cancel pthread twice
which will cause a crash.

Adding a state check in 'stop()' before canceling the pthread to prevent
multiple stop.

Fixes: 696fbc7bb4fc ("net/kni: remove resources when port is closed")

Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
---
 drivers/net/kni/rte_eth_kni.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/kni/rte_eth_kni.c b/drivers/net/kni/rte_eth_kni.c
index 7cba92e2e..d88cb1778 100644
--- a/drivers/net/kni/rte_eth_kni.c
+++ b/drivers/net/kni/rte_eth_kni.c
@@ -156,6 +156,8 @@ eth_kni_dev_start(struct rte_eth_dev *dev)
 	}
 
 	if (internals->no_request_thread == 0) {
+		internals->stop_thread = 0;
+
 		ret = rte_ctrl_thread_create(&internals->thread,
 			"kni_handle_req", NULL,
 			kni_handle_request, internals);
@@ -177,7 +179,7 @@ eth_kni_dev_stop(struct rte_eth_dev *dev)
 	struct pmd_internals *internals = dev->data->dev_private;
 	int ret;
 
-	if (internals->no_request_thread == 0) {
+	if (internals->no_request_thread == 0 && internals->stop_thread == 0) {
 		internals->stop_thread = 1;
 
 		ret = pthread_cancel(internals->thread);
@@ -187,8 +189,6 @@ eth_kni_dev_stop(struct rte_eth_dev *dev)
 		ret = pthread_join(internals->thread, NULL);
 		if (ret)
 			PMD_LOG(ERR, "Can't join the thread");
-
-		internals->stop_thread = 0;
 	}
 
 	dev->data->dev_link.link_status = 0;
-- 
2.21.0