symbolz: skip un-symbolizable mappings

[toddlipcon]

This fixes #339 by skipping
attempts to symbolize anything from system mappings like [vdso],
[vsyscall], etc.

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[codecov-io]

Codecov Report

Merging #340 into master will decrease coverage by 0.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master     #340      +/-   ##
==========================================
- Coverage   66.54%   66.52%   -0.02%     
==========================================
  Files          36       36              
  Lines        7446     7448       +2     
==========================================
  Hits         4955     4955              
- Misses       2089     2090       +1     
- Partials      402      403       +1

Impacted Files	Coverage Δ
internal/symbolz/symbolz.go	77.77% <0%> (-1.97%)	⬇️

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[aalexand]

Doc for the function should be updated.

[aalexand]

You also have to sign the CLA.

[toddlipcon]

I've been through the CLA process a couple years ago and somehow it got lost. Unfortunately going through it again may take some days of clearance with my company's legal team etc. I was under the understanding that for "trivial bug fix" patches like this, CLAs aren't necessary?

[aalexand]

I don't know if there is an exemption from CLA based on the patch size, it's not in my domain of expertise so I have to merely follow the automated CLA pre-submit check and can't merge PRs with that check failed.

[aalexand]

@toddlipcon Do you plan to proceed with signing the CLA? I guess alternatively I can just make the fix myself if you are fine with that.

[toddlipcon]

Sure, I'm fine with that. Sorry for radio silence, on PTO.

…

On Sat, Apr 7, 2018, 9:13 AM Alexey Alexandrov ***@***.***> wrote: @toddlipcon <https://github.com/toddlipcon> Do you plan to proceed with signing the CLA? I guess alternatively I can just make the fix myself if you are fine with that. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#340 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAA3N-jX_MKsQOgM5stRP-3pmvDj8cVoks5tmQ-_gaJpZM4S2Ksw> .

[aalexand]

Superseded by #368.