Drivers: hv: vmbus: Cleanup synic memory free path

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 <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: K. Y. Srinivasan <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
(cherry picked from commit 5720863)

Orabug: 28671425

Signed-off-by: Liam Merwick <[email protected]>
Reviewed-by: Darren Kenny <[email protected]>
Reviewed-by: Alejandro Jimenez <[email protected]>
Tested-by: Vijay Balakrishna <[email protected]>

Author: kelleymh

drivers/hv/hv.c

@@ -242,6 +242,10 @@ 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;
 }
 
@@ -254,12 +258,10 @@ 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);