Drivers: hv: vmbus: Cleanup synic memory free path

[ Upstream commit 572086325ce9a9e348b8748e830653f3959e88b6 ]

clk_evt memory is not being freed when the synic is shutdown
or when there is an allocation error.  Add the appropriate
kfree() call, along with a comment to clarify how the memory
gets freed after an allocation error.  Make the free path
consistent by removing checks for NULL since kfree() and
free_page() already do the check.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 8267439..d8101cd 100644 (file)
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -196,6 +196,10 @@ int hv_synic_alloc(void)
 
        return 0;
 err:
+       /*
+        * Any memory allocations that succeeded will be freed when
+        * the caller cleans up by calling hv_synic_free()
+        */
        return -ENOMEM;
 }
 
@@ -208,12 +212,10 @@ void hv_synic_free(void)
                struct hv_per_cpu_context *hv_cpu
                        = per_cpu_ptr(hv_context.cpu_context, cpu);
 
-               if (hv_cpu->synic_event_page)
-                       free_page((unsigned long)hv_cpu->synic_event_page);
-               if (hv_cpu->synic_message_page)
-                       free_page((unsigned long)hv_cpu->synic_message_page);
-               if (hv_cpu->post_msg_page)
-                       free_page((unsigned long)hv_cpu->post_msg_page);
+               kfree(hv_cpu->clk_evt);
+               free_page((unsigned long)hv_cpu->synic_event_page);
+               free_page((unsigned long)hv_cpu->synic_message_page);
+               free_page((unsigned long)hv_cpu->post_msg_page);
        }
 
        kfree(hv_context.hv_numa_map);