linux-image Suggests cripples old kernel cleanup

Old kernels are not being autoremoved in spite of being marked auto and not being in APT::NeverAutoRemove. Debugging with the pkgAutoRemove "true"; option of APT I can see lines like this:

Following dep: systemtap:amd64 2.3-1ubuntu1 Suggests linux-image:amd64 , provided by linux-image-3.2.0-63-generic:amd64 3.2.0-63.95
Marking: linux-image-3.2.0-63-generic:amd64 3.2.0-63.95, Curr=3.2.0-63.95, Inst=3.2.0-63.95

I can confirm that removing (or marking as auto) systemtap fix the issue.

root # apt-mark auto systemtap
systemtap set to automatically installed.
root # apt-get autoremove
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  libdw1 linux-headers-3.13.0-29 linux-headers-3.13.0-29-generic
  linux-headers-3.13.0-30 linux-headers-3.13.0-30-generic
  linux-headers-3.13.0-32 linux-headers-3.13.0-32-generic
  linux-headers-3.13.0-33 linux-headers-3.13.0-33-generic
  linux-headers-3.13.0-34 linux-headers-3.13.0-34-generic
  linux-headers-3.13.0-35 linux-headers-3.13.0-35-generic
  linux-headers-3.13.0-36 linux-headers-3.13.0-36-generic
  linux-headers-3.13.0-37 linux-headers-3.13.0-37-generic
  linux-headers-3.13.0-39 linux-headers-3.13.0-39-generic
  linux-headers-3.13.0-40 linux-headers-3.13.0-40-generic
  linux-headers-3.13.0-43 linux-headers-3.13.0-43-generic
  linux-headers-3.13.0-44 linux-headers-3.13.0-44-generic
  linux-headers-3.13.0-46 linux-headers-3.13.0-46-generic
  linux-headers-3.13.0-48 linux-headers-3.13.0-48-generic
  linux-headers-3.13.0-49 linux-headers-3.13.0-49-generic
  linux-headers-3.13.0-51 linux-headers-3.13.0-51-generic
  linux-headers-3.13.0-52 linux-headers-3.13.0-52-generic
  linux-headers-3.13.0-53 linux-headers-3.13.0-53-generic
  linux-headers-3.13.0-54 linux-headers-3.13.0-54-generic
  linux-headers-3.13.0-55 linux-headers-3.13.0-55-generic
  linux-headers-3.13.0-58 linux-headers-3.13.0-58-generic
  linux-headers-3.13.0-59 linux-headers-3.13.0-59-generic
  linux-headers-3.13.0-61 linux-headers-3.13.0-61-generic
  linux-image-3.13.0-29-generic linux-image-3.13.0-30-generic
  linux-image-3.13.0-32-generic linux-image-3.13.0-33-generic
  linux-image-3.13.0-34-generic linux-image-3.13.0-35-generic
  linux-image-3.13.0-36-generic linux-image-3.13.0-37-generic
  linux-image-3.13.0-39-generic linux-image-3.13.0-40-generic
  linux-image-3.13.0-43-generic linux-image-3.13.0-44-generic
  linux-image-3.13.0-46-generic linux-image-3.13.0-48-generic
  linux-image-3.13.0-49-generic linux-image-3.13.0-51-generic
  linux-image-3.13.0-52-generic linux-image-3.13.0-53-generic
  linux-image-3.13.0-54-generic linux-image-3.13.0-55-generic
  linux-image-3.13.0-58-generic linux-image-3.13.0-59-generic
  linux-image-3.13.0-61-generic systemtap systemtap-common systemtap-runtime
0 upgraded, 0 newly installed, 73 to remove and 88 not upgraded.
After this operation, 2,740 MB disk space will be freed.

# lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04

 # apt-cache policy systemtap
systemtap:
  Installed: 2.3-1ubuntu1
  Candidate: 2.3-1ubuntu1
  Version table:
 *** 2.3-1ubuntu1 0
        500 http://us.archive.ubuntu.com/ubuntu/ trusty/universe amd64 Packages
        100 /var/lib/dpkg/status