[CRIU] stray unix socket not dumped by the diag module?

[Tycho Andersen]

On Thu, Jul 14, 2016 at 02:00:32PM +0300, Pavel Emelyanov wrote:
> On 07/13/2016 05:53 PM, Tycho Andersen wrote:
> > On Wed, Jul 13, 2016 at 04:53:53PM +0300, Pavel Emelyanov wrote:
> >> On 07/13/2016 01:42 AM, Tycho Andersen wrote:
> >>> Hi guys,
> >>>
> >>> I'm getting a,
> >>>
> >>> (00.155898) Error (sk-unix.c:294): sk unix: Unix socket 0x5674 not found
> >>>
> >>> very rarely when dumping containers. This looks to be some kind of
> >>> unix socket that systemd has open, full log here:
> >>>
> >>> http://paste.ubuntu.com/19219914/
> >>>
> >>> but somehow, this socket didn't get dumped in collect_sockets(). I
> >>> looked through the kernel code, but it's not obvious to me why a
> >>> socket would be missing. Any ideas where to start digging?
> >>
> >> I guess it's the same issue as for TCP sockets -- only bind()-ed or auto-bound
> >> sockets get into the list reported by the kernel.
> > 
> > I see, because they're not in the unix_socket_table I suppose. It
> > looks like maybe we can get info on these sockets from the diag module
> > by doing a specific request for them based on their inode number; is
> > that the right approach?
> 
> Nope, the per-socket diag works on the same hash table :( We've met this
> with TCP sockets already, see the gen_uncon_sk() function in criu/sk-inet.c,
> I guess we need smth similar for unix sockets.

Thanks, I missed that. I'll have a look at gen_uncon_sk and see what
we can do for unix sockets.

Tycho