[PATCH] IPMI oops fix

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: NPaolo Galtieri <pgaltieri@mvista.com>
Acked-by: NCorey Minyard <cminyard@mvista.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/char/ipmi/ipmi_si_intf.c

@@ -2399,7 +2399,8 @@ static int init_one_smi(int intf_num, struct smi_info **smi)
 			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;
 }
@@ -2518,7 +2519,8 @@ static void __exit cleanup_one_si(struct smi_info *to_clean)
 
 	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)