2008-02-18 21:03:22

by Glauber Costa

[permalink] [raw]
Subject: [PATCH 0/4] Avoid panic in case of buggy bios

Hi,

I've came across a panic today after failing acpi_processor_start()
in this condition:

if (processor_device_array[pr->id] != NULL &&
processor_device_array[pr->id] != device) {
printk(KERN_WARNING "BIOS reported wrong ACPI id "
"for the processor\n");
return -ENODEV;
}

The problem is that there are some data structures that are not initialized
if we exit that early, but the removal functions assume to be present. One
solution would be to move the checks to the bottom of this function, after
all the initializations are complete, but I personally think this is
not a good idea, from the waste point of view.

So I'm attaching a series of 4 patches that provides a criteria to decide
whether or not we got past the point of initializing that data structures,
and using it to conditionally unregister them latter.

Hope it's okay with you