Re: 2.6.23-rc2-mm2

Eric W. Biederman
2007-08-10T21:21:22Z

Andrew Morton <akpm@linux-foundation.org> writes:

> There seems to be rather a lot of damage here.
>
> I assume that the sysctl changes are what caused the netfilter oopses.
>
> - nf_conntrack_init() calls nf_conntrack_expect_init() which fails due to
> sysctl problems.

In particular sysctl_check_table finds issues with the sysctl table
so register_sysctl_table refuses to register it.

> - nf_conntrack_init() bales out without calling nf_conntrack_helper_init()
>
> So nf_ct_helper_hsize never gets initialised.
>
> - Later, netfilter client code calls helper_hash(), which gets a
> divide-by-zero due to nf_ct_helper_hsize==0.
>
>
> yeah, that's a netfilter bug, but we're trying to get kernels tested here.
> If I'm feeling energetic I'll drop the sysctl changes and do rc2-mm3.
> Probably I won't feel energetic, but we'll need a lot of fixes here before
> I can release the sysctl changes in another -mm, please.

As a cheap workaround it should be possible to disable SYSCTL support
in 2.6.23-rc2-mm2 to get around these issues.

Andrew for the moment I have just sent you fixes for all of the issues
that I am aware of. Mostly they are cheap kill the sys_sysctl()
support patches.

Hopefully that is enough to bring the pain level down to manageable.

I hadn't anticipated subsystems failing because they could not register
their sysctl tables. I was simply expecting things not to show up in
/proc/sys. And more of the pain of making working sysctl tables to
be pushed back to developers.

Eric