You're entering "linux-kernel" when the correct value would be simply "linux". It's still a bug that Launchpad OOPSes in this case rather than giving a useful error message (I'm pretty sure there's already a bug report about this somewhere, but I can't find it right now), but if you enter "linux" rather than "linux-kernel" then it should work.
You're entering "linux-kernel" when the correct value would be simply "linux". It's still a bug that Launchpad OOPSes in this case rather than giving a useful error message (I'm pretty sure there's already a bug report about this somewhere, but I can't find it right now), but if you enter "linux" rather than "linux-kernel" then it should work.