Re: MSR support for x86

Ingo Molnar (mingo@pc5829.hil.siemens.at)
Tue, 11 Mar 1997 09:15:02 +0100 (MET)


On 10 Mar 1997, Wayne Schlitt wrote:

> > > [ ... ] but that's not the point. The point is that
> > > some of this information can be used in surprising ways and I think we
> > > should be really careful what we allow general users to access.
> >
> > This all misses the point. The whole reason for /dev files with
> > permissions is so people can set them.
>
> [ note: my original comments edited back in, slightly out of context ]
>
> yes, the UNIX philosophy of "everything is a file", and can be
> protected as such, is A Good Thing. However, these "unexpected
> consequences" lead me to believe that having separate files for each
> of the MSR's would be better than putting them all in one file and
> doing seeks.

check out the implementation of /dev/mem, /dev/kmem, /dev/port, /dev/full,
(etc.), and see how /dev/msr fits into this picture. The sources are in
drivers/char/mem.c.

if you've got some cool new abstraction for MSRs, maybe you should extend
it to the above devices too.

-- mingo