manager: warn if a device steals an existing interface

This is not cool; warn about it. Let's not remove it yet to stay on the
safe side.
12 jobs for lr/manager-no-steal in 94 minutes and 32 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Test
passed #310403
allowed to fail
checkpatch

00:01:04

passed #310410
t_debian:9

00:20:30

passed #310412
t_debian:sid

00:18:23

manual #310411
allowed to fail manual
t_debian:testing
passed #310404
t_fedora:28

00:27:32

passed #310405
t_fedora:29

00:37:30

failed #310406
t_fedora:30

01:34:32

manual #310407
allowed to fail manual
t_fedora:rawhide
passed #310408
t_ubuntu:16.04

00:21:04

failed #310409
t_ubuntu:18.04

00:18:32

 
  External
passed NetworkManager test verification

passed NetworkManager test verification

05:57:08

 
Name Stage Failure
failed
t_fedora:30 Test There has been a timeout failure or the job got stuck. Check your timeout limits or try again
PASS: src/platform/tests/test-link-linux 47 /link/software/detect/vxlan/0/platform
PASS: src/platform/tests/test-link-linux 48 /link/software/detect/vxlan/0/random
PASS: src/platform/tests/test-link-linux 49 /link/software/detect/vxlan/1/external
PASS: src/platform/tests/test-link-linux 50 /link/software/detect/vxlan/1/platform
PASS: src/platform/tests/test-link-linux 51 /link/software/detect/vxlan/1/random
SKIP: src/platform/tests/test-link-linux 52 /link/software/detect/wireguard/0/external # SKIP wireguard not supported (modprobe wiregPASS: src/ndisc/tests/test-ndisc-fake 1 /ndisc/simple
PASS: src/ndisc/tests/test-ndisc-fake 2 /ndisc/everything-changed
PASS: src/ndisc/tests/test-ndisc-fake 3 /ndisc/preference-order
PASS: src/ndisc/tests/test-ndisc-fake 4 /ndisc/preference-changed
PASS: src/ndisc/tests/test-ndisc-fake 5 /ndisc/dns-solicit-loop
failed
t_ubuntu:18.04 Test
+ case "$1" in
+ return 0
+ test 1 == 1
+ return 0
+ echo '>>>> PRINT VALGRIND LOGS (valgrind test) (start)'
>>>> PRINT VALGRIND LOGS (valgrind test) (start)
+ find -name '*.valgrind-log' -print0
+ xargs -0 grep -H '^'
ERROR: Job failed: exit code 1