[CRIU] ERROR -2 reported by netlink (No such file or directory)

[Cyrill Gorcunov]

On Wed, Dec 12, 2018 at 12:23:32PM +0100, Adrian Reber wrote:
> Hello Cyrill,
> 
> I saw a few commits from you related to 'inet: raw'. I hope you are the
> right person for my problem. On my RHEL7 system I get following line in
> CRIU's dump.log:
> 
> # (00.004061) unix: 	Collected: ino 75689 peer_ino 0 family    1 type    5 state  7 name (null)
> # (00.004170) Error (criu/libnetlink.c:27): ERROR -2 reported by netlink (No such file or directory)
> # (00.004176) Warn  (criu/sockets.c:791): sockets: The current kernel doesn't support ipv4 raw_diag module
> # (00.004271) Error (criu/libnetlink.c:27): ERROR -2 reported by netlink (No such file or directory)
> # (00.004274) Warn  (criu/sockets.c:834): sockets: The current kernel doesn't support ipv6 raw_diag module

Hi Adrian! Yes, I wrote the code for inet raw support. You know there are
several problems in one stack: 1) Recent (but not latest) kernels doesn't
support of autoloading of raw modules via diag interface. Andrew fixed it
recently but I'm not sure how much time will pass until the patch hit
all distros; 2) There was a series https://patchwork.criu.org/series/3124/
which should placate error messaging when used together with Andrew's fix.

What is more inconvenient I think is that we have to live with old kernels
and I think should not issue an error in this case.

That said, gimme some time I'll try to figure out what we can do about
it. Hopefully I'll manage today, ok?