xen/mce: fix up xen_late_init_mcelog() error handling

Static checkers complain about the missing call to misc_deregister() if
bind_virq_for_mce() fails.

Also I reversed the tests so that we do error handling instead of
success handling.  That way we just have a series of function calls
instead of the more complicated nested if statements in the original
code.  Let's preserve the error codes as well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>

diff --git a/drivers/xen/mcelog.c b/drivers/xen/mcelog.c
index 6ab6a79..a493c73 100644 (file)
--- a/drivers/xen/mcelog.c
+++ b/drivers/xen/mcelog.c
@@ -393,14 +393,25 @@ static int bind_virq_for_mce(void)
 
 static int __init xen_late_init_mcelog(void)
 {
+       int ret;
+
        /* Only DOM0 is responsible for MCE logging */
-       if (xen_initial_domain()) {
-               /* register character device /dev/mcelog for xen mcelog */
-               if (misc_register(&xen_mce_chrdev_device))
-                       return -ENODEV;
-               return bind_virq_for_mce();
-       }
+       if (!xen_initial_domain())
+               return -ENODEV;
+
+       /* register character device /dev/mcelog for xen mcelog */
+       ret = misc_register(&xen_mce_chrdev_device);
+       if (ret)
+               return ret;
+
+       ret = bind_virq_for_mce();
+       if (ret)
+               goto deregister;
 
-       return -ENODEV;
+       return 0;
+
+deregister:
+       misc_deregister(&xen_mce_chrdev_device);
+       return ret;
 }
 device_initcall(xen_late_init_mcelog);