internal error: looping module stopped

[Aleš Rygl]

Hello,

While inspecting unbound logs after an upgrade to Unbound 1.6.0-3+deb9u1 I have found some errors like this:

Sep 19 12:40:45 unbound[16337:22] error: internal error: looping module stopped
Sep 19 12:40:45 unbound[16337:22] error: internal error: looping module stopped
Sep 19 12:41:00 unbound[16337:21] error: internal error: looping module stopped
Sep 19 12:41:00 unbound[16337:21] error: internal error: looping module stopped
Sep 19 12:41:01 unbound[16337:4] error: internal error: looping module stopped
Sep 19 12:41:01 unbound[16337:4] error: internal error: looping module stopped
Sep 19 12:41:46 unbound[16337:2e] error: internal error: looping module stopped
Sep 19 12:41:46 unbound[16337:2e] error: internal error: looping module stopped
Sep 19 12:42:32 unbound[16337:29] error: internal error: looping module stopped
Sep 19 12:42:32 unbound[16337:29] error: internal error: looping module stopped
Sep 19 12:43:11 unbound[16337:2a] error: internal error: looping module stopped
Sep 19 12:43:11 unbound[16337:2a] error: internal error: looping module stopped

I have six instances of Unbound and I can see it on all of them. The load is up to 500qps, DNSSEC enabled, use-caps-for-id enabled, IPv6. 

Thanks

With regards
Ales