# Re: \[PATCH 0/59\] Cleanup sysctl

- From: H. Peter Anvin \<hpa@zytor.com\>
- Date: 2007-01-16 17:15:31 
- List: linuxppc-dev
- Page: https://ratatoskr.run/linuxppc-dev/2007/01/912073
- Thread: https://ratatoskr.run/netdev/2007/01/912004/t.md

```text
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
```