java: Paranoid profiling stop on suspicious events in kernel messages #235
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Merged
d3dave
reviewed
Dec 1, 2021
| self._disable_profiling() # paranoia | ||
| continue | ||
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| if self._java_safemode: |
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if java safemode and profiling enabled
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This is on purpose actually, The system-wide things - I want to continue collecting them also after profiling was stopped (so I can understand whether it was an anomaly or not)
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I won't have profiled PIDs anymore, that's true
d3dave
approved these changes
Dec 1, 2021
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Description
We want the ability to be very strict on error detection. This is possibly too strict (segfaults in non-profiled processes are most likely not related to us...) but we'll start very strict and lower the bar as we go.
The "PID in message" check will help us identify if our regex on OOM/signals miss anything (or if there's any other type of bad message we should be looking at). I hope it won't catch too many false positives.
How Has This Been Tested?
docker run -it -m 6m pythonand made sure Java profiling stopsmain(){*(int*)0=0;}and made sure Java profiling stopsecho 374075 | sudo tee /dev/kmsg) and made sure Java profiling stops. It's funny that it works - the kernel does flag messages coming from usermode, we should check this flag and ignore such messages as we really care only about kernel messages.