I can see a reference to "/boot/bzImage" in both buildhistory and tmp-glibc/work/.../pkgdata [1] after running a clean rebuild of virtual/kernel [2].
[1] file paths:
"buildhistory/packages/qemux86-oe-linux/linux-yocto/kernel- image-bzimage/files-in-package .txt"
"tmp-glibc/work/qemux86-oe-linux/linux-yocto/4.12.12+gitAUTO INC+eda4d18ce4_16de014967-r0/ pkgdata/runtime/kernel-image- bzimage"
[2] clean rebuild command:
bitbake -c cleanall virtual/kernel
bitbake virtual/kernel
Which file are you diffing? Could you share the full path?