From: Evgeniy Polyakov <redacted>
Date: Wed, 21 Mar 2007 13:58:47 +0300

On Wed, Mar 21, 2007 at 11:54:45AM +0100, Patrick McHardy (kaber@trash.net) wrote:

quoted

Evgeniy Polyakov wrote:

quoted

We would already do that on init.
Some things become very confused, when nl_table is not used to store
netlink sockets.

Its unnecessary, but I don't understand what the problem is.
Why would it be NULL and what gets confused?

There is no problem as-is, but I implement unified cache for different
sockets (currently tcp/udp/raw and netlink are supported), which does
not use that table, so I currently wrap all access code into special
ifdefs, this one can be wrapped too, but since it is not needed, it
saves couple of lines of code.

It is needed.  It is there to make sure that a kernel netlink
socket is not created before the af_netlink init code runs.

We've had sequencing bugs like that in the initcall call chain
in the past, that's why the check is there.