From 09a1028e0fc36cfeccf7554c69f92bef8eb72b14 Mon Sep 17 00:00:00 2001
From: GangCao <gang.cao@intel.com>
Date: Tue, 23 Mar 2021 15:25:08 -0400
Subject: [PATCH] nvme: fix double free of g_hotplug_probe_ctx

Add a check and only free g_hotplug_probe_ctx once.

This is to fix below issue:
https://github.com/spdk/spdk/issues/1849

Change-Id: I7387495890830badd06a7341d9ac4d149ca1c9f4
Signed-off-by: GangCao <gang.cao@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/7002
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Xiaodong Liu <xiaodong.liu@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: <dongx.yi@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
---
 module/bdev/nvme/bdev_nvme.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/module/bdev/nvme/bdev_nvme.c b/module/bdev/nvme/bdev_nvme.c
index 620117def..6ff829b76 100644
--- a/module/bdev/nvme/bdev_nvme.c
+++ b/module/bdev/nvme/bdev_nvme.c
@@ -1812,6 +1812,11 @@ remove_cb(void *cb_ctx, struct spdk_nvme_ctrlr *ctrlr)
 static int
 bdev_nvme_hotplug_probe(void *arg)
 {
+	if (g_hotplug_probe_ctx == NULL) {
+		spdk_poller_unregister(&g_hotplug_probe_poller);
+		return SPDK_POLLER_IDLE;
+	}
+
 	if (spdk_nvme_probe_poll_async(g_hotplug_probe_ctx) != -EAGAIN) {
 		g_hotplug_probe_ctx = NULL;
 		spdk_poller_unregister(&g_hotplug_probe_poller);
@@ -2276,6 +2281,7 @@ bdev_nvme_library_fini(void)
 
 	spdk_poller_unregister(&g_hotplug_poller);
 	free(g_hotplug_probe_ctx);
+	g_hotplug_probe_ctx = NULL;
 
 	TAILQ_FOREACH_SAFE(entry, &g_skipped_nvme_ctrlrs, tailq, entry_tmp) {
 		TAILQ_REMOVE(&g_skipped_nvme_ctrlrs, entry, tailq);