Re: [PATCH 0/59] Cleanup sysctl

H. Peter Anvin
2007-01-16T17:15:31Z

Eric W. Biederman wrote:
>
> - Removal of sys_sysctl support where people had used conflicting sysctl
> numbers. Trying to break glibc or other applications by changing the
> ABI is not cool. 9 instances of this in the kernel seems a little
> extreme.
>

It would be highly advantageous if we could have a file that acts as a
central registry of architectural sysctl numbers *and have the numbers
in the kernel derived from there*. As I've said before, I don't really
think sys_sysctl is any worse than ad hoc system calls (sys_mips and the
like), but the real problem is that there are architectural and
non-archtectural numbers, and they're mixed in all over the place.

I think it would be fair to say that if they're not in <linux/sysctl.h>
they're not architectural, but that doesn't resolve the counterpositive
(are there sysctls in <linux/sysctl.h> which aren't architectural? From
the looks of it, I would say yes.) Non-architectural sysctl numbers
should not be exported to userspace, and should eventually be rejected
by sys_sysctl.

-hpa