[PATCH v4 6/8] eal/freebsd: fix interrupt source handle leak

[Anatoly Burakov]

Each interrupt source keeps a private copy of the interrupt handle it was
registered with, but the copy is never freed when the source is removed,
leaking the handle and its event arrays.

Free the copy with the source. The copy owns none of the file
descriptors it references, so clear them first.

Fixes: bbbac4cd6ed2 ("interrupts: remove direct access to interrupt handle")
Cc: stable at dpdk.org

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
---
 lib/eal/freebsd/eal_interrupts.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/lib/eal/freebsd/eal_interrupts.c b/lib/eal/freebsd/eal_interrupts.c
index bb2bc529f2e..09ba76b378f 100644
--- a/lib/eal/freebsd/eal_interrupts.c
+++ b/lib/eal/freebsd/eal_interrupts.c
@@ -57,6 +57,25 @@ static rte_thread_t intr_thread;
 
 static volatile int kq = -1;
 
+/*
+ * An interrupt source holds a copy of the handle it was registered with
+ * and owns none of the file descriptors. Clear the references before
+ * freeing the copy so they are not reported as leaks.
+ */
+static void
+eal_intr_source_free(struct rte_intr_source *src)
+{
+	struct rte_intr_handle *intr_handle = src->intr_handle;
+	int i;
+
+	rte_intr_fd_set(intr_handle, -1);
+	rte_intr_dev_fd_set(intr_handle, -1);
+	for (i = 0; i < rte_intr_nb_intr_get(intr_handle); i++)
+		rte_intr_efds_index_set(intr_handle, i, -1);
+	rte_intr_instance_free(intr_handle);
+	free(src);
+}
+
 static int
 intr_source_to_kevent(const struct rte_intr_handle *ih, struct kevent *ke)
 {
@@ -204,7 +223,7 @@ rte_intr_callback_register(const struct rte_intr_handle *intr_handle,
 			TAILQ_REMOVE(&(src->callbacks), callback, next);
 		if (TAILQ_EMPTY(&(src->callbacks))) {
 			TAILQ_REMOVE(&intr_sources, src, next);
-			free(src);
+			eal_intr_source_free(src);
 		}
 	}
 	free(callback);
@@ -347,7 +366,7 @@ rte_intr_callback_unregister(const struct rte_intr_handle *intr_handle,
 		/* all callbacks for that source are removed. */
 		if (TAILQ_EMPTY(&src->callbacks)) {
 			TAILQ_REMOVE(&intr_sources, src, next);
-			free(src);
+			eal_intr_source_free(src);
 		}
 	}
 out:
@@ -592,7 +611,7 @@ eal_intr_process_interrupts(struct kevent *events, int nfds)
 		/* all callbacks for that source are removed. */
 		if (TAILQ_EMPTY(&src->callbacks)) {
 			TAILQ_REMOVE(&intr_sources, src, next);
-			free(src);
+			eal_intr_source_free(src);
 		}
 
 		rte_spinlock_unlock(&intr_lock);
-- 
2.52.0