[bionic:linux-azure-4.15][PATCH 3/9] Drivers: hv: vmbus: Fix the issue with freeing up hv_ctl_table_hdr

[Marcelo Henrique Cerri]

From: Sunil Muthuswamy <sunilmut at microsoft.com>

BugLink: http://bugs.launchpad.net/bugs/1875456

The check to free the Hyper-V control table header was reversed. This
fixes it.

Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic")

Signed-off-by: Sunil Muthuswamy <sunilmut at microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys at microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
(cherry picked from commit 8afc06dd75c06b9d6e70e4a72fdafbd4cab8d1df)
Signed-off-by: Marcelo Henrique Cerri <marcelo.cerri at canonical.com>
---
 drivers/hv/vmbus_drv.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index c83b5c253e30..678576db5273 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -1226,11 +1226,8 @@ static int vmbus_bus_init(void)
 
 	bus_unregister(&hv_bus);
 	free_page((unsigned long)hv_panic_page);
-	if (!hv_ctl_table_hdr) {
-		unregister_sysctl_table(hv_ctl_table_hdr);
-		hv_ctl_table_hdr = NULL;
-	}
-
+	unregister_sysctl_table(hv_ctl_table_hdr);
+	hv_ctl_table_hdr = NULL;
 	return ret;
 }
 
@@ -1927,11 +1924,8 @@ static void __exit vmbus_exit(void)
 	}
 
 	free_page((unsigned long)hv_panic_page);
-	if (!hv_ctl_table_hdr) {
-		unregister_sysctl_table(hv_ctl_table_hdr);
-		hv_ctl_table_hdr = NULL;
-	}
-
+	unregister_sysctl_table(hv_ctl_table_hdr);
+	hv_ctl_table_hdr = NULL;
 	bus_unregister(&hv_bus);
 
 	cpuhp_remove_state(hyperv_cpuhp_online);
-- 
2.25.1