Re: [RFC] prevent "dd if=/dev/mem" crash

Andrew Morton
2003-10-18T01:41:11Z

Matt Chapman <matthewc@cse.unsw.edu.au> wrote:
>
> It *does* signal a fault, in the form of a machine check. On other
> architectures I'm familiar with this is usually implemented as an
> interrupt, but the idea is similar - when the system bus controller
> detects a bad address on the bus, it returns all 1s (for a read) and
> signals an interrupt.

I see. That seems OK. At least it means that software can implement a
probing function and that the time interval between hot unplug and handling
the unplug interrupt can be managed appropriately.