Comment 7 for bug 2045443

You can file a bug just like you did. If you happen to do a bit more debugging, then making sure it gets assigned to the correct package helps.

For the kernel, always just file a new bug, unless someone has the same issue as you and you can find the bug via google or the all bugs category on the kernel package on launchpad.

For server packages like systemd, bind9, etc, its best to file those issues against the package itself. You can review the changelog to see what changed lately, and say, if the latest change causes a regression, you can write a comment to the launchpad bug for that change instead of filing a new report.