Debian9 Kernel4.19 Build Failed

@yonghong-song
Today, I try to build the bcc in a total new debian9 system. At firest, the bcc dependebce are all going well and had be installed on my Db9 successfully. But, when try to use the commnd `debuild -b -uc -us` to **build the bcc form the source** , it can not pass all tests, some tests failed for importerror**have no module name bcc** ,and some failed for **Cannot get device udp-fragmentation-offload settings: Operation not supported** , could tell me why or tell me does bcc require specific directory path?

Start by reproducing the Debian 9 build with `debuild -b -uc -us` and capture which tests report `No module named bcc` or the UDP offload error. Trace the build and test setup to determine whether the failures are environment-specific or indicate a project issue; done means the cause and a reproducible fix or documented limitation are identified.

Written by the indexing model from the issue text.