Re: [PATCH] DevFS support for /dev/cpu/X/(cpuid|msr)

Richard Gooch
2002-01-06T21:13:42Z

H. Peter Anvin writes:
> Matt Dainty wrote:
>
> > Okey dokey,
> >
> > Please find attached a second, better patch to add devfs support to the i386
> > cpuid and msr drivers. Now it doesn't nuke the cpu/X directories on
> > unloading and only enumerates CPUs based on smp_num_cpus instead of NR_CPUS.
>
> If you don't understand why this is idiotic, then let me enlighten you:
> there is no sensible reason why /dev/cpu/%d should only be populated
> after having run a CPU-dependent device driver. /dev/cpu/%d should be
> always populated; heck, that's the only way you can sensibly handle
> hotswapping CPUs.

I've already privately told Matt that it would be nice if creation of
/dev/cpu/%d was handled by generic boot code, and not a driver.
However, I don't see that as essential for the CPUID and MSR drivers.

> I WILL NOT accept a patch as long as devfs is as fucked in the head
> as it currently is. Unfortunately, that seems like it will be a
> long long time.

No need to get rude.

Regards,

Richard....
Permanent: rgooch@atnf.csiro.au
Current: rgooch@ras.ucalgary.ca