probe kprocess.create broken

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probe kprocess.create broken

Torsten Polle
Hi Frank,

While trying to update to the head version of SystemTap, I found that the following commit breaks my system (Linux legolas 4.15.0-101-generic #102~16.04.1-Ubuntu SMP Mon May 11 11:38:16 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux)

HEAD is now at 13d1ba6 PR12609 redux: filter out duplicate probes due to partial-inining
13d1ba6b86e806097e8c70777474f76cee182a25 is the first bad commit
commit 13d1ba6b86e806097e8c70777474f76cee182a25
Author: Frank Ch. Eigler <[hidden email]>
Date:   Fri Apr 10 20:37:06 2020 -0400
 PR12609 redux: filter out duplicate probes due to partial-inining

 Ever since gcc 4.7ish, partially-inlined functions can sometimes show
 up as separate top-level functions named FOO.part.* in the ELF symbol
 table, but identifed as ordinary function FOO in DWARF.  The latter
 means that stap would probe both the partially inlined part of the
 function, and the non-inlined second part, for a plain .function()
 probe.  This new code suppresses the probe on the .part. one, based
 on a symbol name heuristic.

 Also RHBZ1169184.

I can no longer use the probe ‚kprocess.create'.

Pass 1: parsed user script and 477 library scripts using 93140virt/66480res/5432shr/61172data kb, in 270usr/10sys/295real ms.
WARNING: cannot probe .return of 1 inlined functions  copy_process
semantic error: while resolving probe point: identifier 'kernel' at /usr/local/systemtap/share/systemtap/tapset/linux/kprocess.stp:29:25
     source: probe kprocess.create = kernel.function("copy_process").return {
                                     ^
semantic error: no match (similar functions: copy_process, klp_copy_process, rcu_copy_process, arp_process, zap_process)
semantic error: resolution failed in alias expansion builder
semantic error: no match
Pass 2: analyzed script: 7 probes, 38 functions, 7 embeds, 4 globals using 293220virt/268136res/7108shr/261252data kb, in 59690usr/9730sys/38366real ms.
Pass 2: analysis failed.  [man error::pass2]

Kind Regards,
Torsten