Collect and report kernel warnings.

A flex-based daemon collects kernel warnings by parsing /var/log/messages
as lines are added to it.  For every warning the daemon sends a sample
to a sparse UMA histogram using a hash of the warning as the bucket.
Then, if the warning hasn't been seen before, the daemon invokes the
crash collector to upload the warning stack trace.

TEST=manually tested (for now), automated test on its way

Change-Id: I89090e5c2b61ec46b4e740f0895c591728d70e77
Commit-Queue: Luigi Semenzato <>
Reviewed-by: Luigi Semenzato <>
Tested-by: Luigi Semenzato <>
9 files changed
tree: 5f8ec6a39f3c2965044e10dc028d53c86954eb53
  1. crash_reporter/