While doing some testing I discovered that if the BIOS on a board does not
properly setup the DMI information it leads to a panic in the IPMI code.
The panic is due to dereferencing a pointer which is not initialized.  The
pointer is initialized in port_setup() and/or mem_setup() and used in
init_one_smi() and cleanup_one_si(), however if either port_setup() or
mem_setup() return ENODEV the pointer does not get initialized.
Signed-off-by: Paolo Galtieri <pgaltieri@mvista.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
                        new_smi->handlers->cleanup(new_smi->si_sm);
                kfree(new_smi->si_sm);
        }
-       new_smi->io_cleanup(new_smi);
+       if (new_smi->io_cleanup)
+               new_smi->io_cleanup(new_smi);
 
        return rv;
 }
 
        kfree(to_clean->si_sm);
 
-       to_clean->io_cleanup(to_clean);
+       if (to_clean->io_cleanup)
+               to_clean->io_cleanup(to_clean);
 }
 
 static __exit void cleanup_ipmi_si(void)