Exception: Failed to attach BPF program b'trace_req_completion' to kprobe b'blk_account_io_completion'

[Bobby B]

5.8 HWE kernel dies with the following exception:

cannot attach kprobe, probe entry may not exist
Traceback (most recent call last):
  File "/usr/sbin/biosnoop-bpfcc", line 162, in <module>
    b.attach_kprobe(event="blk_account_io_completion",
  File "/usr/lib/python3/dist-packages/bcc/__init__.py", line 658, in attach_kprobe
    raise Exception("Failed to attach BPF program %s to kprobe %s" %
Exception: Failed to attach BPF program b'trace_req_completion' to kprobe b'blk_account_io_completion'

5.8 HWE kernel does not have a kprobe.blk_account_io_completion but does have a kprobe.blk_account_io_done. Modifying allows this script to run. Perhaps you could generate some tests to confirm that the relevant kprobes are available?