Well this is more about the user space tool perf, not really the kernel
itself. And I can't really imagine why DWARF unwinding would have
anything to do with the kernel used. I'm on stock ubuntu
4.13.0-38-generic btw.

When I compile perf from the kernel source (commit
2bf1ab321a06a7faeb95c56d02139140fb56199a) it seems that it fails when
only having libdw-dwarf-unwind as system feature. When having both
libdw-dwarf-unwind and libunwind available the compiled perf does not
fail the test. I think that for DWARF unwinding either one of those two
libraries should be enough, so maybe this is a bug in libdwarf or how
perf uses libdwarf, and when libunwind is available it uses it instead.
But just a wild guess, I don't really know what's going on.

In any case, a quick "fix" seems to be building perf with libunwind -
even if that just masks the actual bug here.

** Changed in: linux (Ubuntu)
       Status: Incomplete => Confirmed

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  perf DWARF unwind failed

Status in linux package in Ubuntu:

Bug description:
  Ubuntu 17.10. To reproduce:

  $ perf test
  57: DWARF unwind                               : FAILED!

  It seems perf is somehow mis-configured.

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