They seem to come from runqemu and for each runqemu run, a new level of duplication is added. This happens sometimes and not others, generally on newer autobuilders but doesn't always happen.

*** Bug 12257 has been marked as a duplicate of this bug. ***

Starting to suspect this happens when there is a server reconnection. Each reconnection adds extra log duplication.

(In reply to comment #3)
> Starting to suspect this happens when there is a server reconnection. Each
> reconnection adds extra log duplication.

The qemu runner adds a new stream handler [1] when is lunched, the testimage class uses the main logger [2] and the oe-selftest script also initialize its own logger [3].

For me the qemu runner needs to use the logger from outside (testimage, selftest), instead of add every time an StreamHandler [3] that cuases the duplication. [4]



[1]  http://git.yoctoproject.org/cgit/cgit.cgi/poky/tree/meta/lib/oeqa/utils/qemurunner.py#n60
[2] http://git.yoctoproject.org/cgit/cgit.cgi/poky/tree/meta/classes/testimage.bbclass#n160
[3] http://git.yoctoproject.org/cgit/cgit.cgi/poky/tree/scripts/oe-selftest#n46
[4] http://git.yoctoproject.org/cgit/cgit.cgi/poky/tree/meta/lib/oeqa/utils/commands.py#n331

http://git.yoctoproject.org/cgit.cgi/poky/commit/?id=a87cae5bb1b0168b29eef7076756ef1d7179ee72 and the preceding 8 commits address this issue. Appears that a python bug was fixed in 3.6 which started exposing these messages.

http://git.yoctoproject.org/cgit.cgi/poky/commit/?id=729b1d3afd3d4b8eed4a4f4ddeb27780db47dcd5 in particular.