Re: [PATCH] exec: Make do_coredump more robust and safer when using pipes in core_pattern

Andrew Morton
2009-06-28T20:53:33Z

On Sun, 28 Jun 2009 21:31:12 +0200 Andi Kleen <andi@firstfloor.org> wrote:

> > One way would be to add a new sysctl-externs.h and then put all the
> > declarations in there. That file gets included by sysctl.c and by each
> > file which shares a global with sysctl.c
>
> Long ago I had a experimental patch to put sysctls into a new ELF section. The
> you could simply put a DEFINE_SYSCTL(....) into the appropiate source file
> which defined the variable and most of the tables went.
>
> No externs, no mess, no patch collisions, everything much nicer.
>
> The only problem was that it didn't support the numerical sysctl
> space, so that would need to be removed first.
>
> It's deprecated for quite some time now:
>
> if (msg_count < 5) {
> msg_count++;
> printk(KERN_INFO
> "warning: process `%s' used the deprecated sysctl "
> "system call with ", current->comm);
>
> Should it finally go now? If yes I could polish up the old patch again.
>

I suspect that it will be a long time before we can actually remove the
numerical sysctl support, if ever. In _theory_ we should support it
for ever. But in practice, we could probably remove it with a minimum
of disruption a few years hence, but it's hard to work this out.

When was the last time we saw a "warning: process `%s' used the
obsolete bdflush system call" warning? A quick google here says 2004.
Is that data? A bit, I guess.

Maybe Eric has thought about this issue?