When manager is stopped there are sometimes runaway qemu
processes still running. Set PDEATHSIG for all subprocesses.
We never need child processes outliving parents.
It's currently both optional and non optional.
We require it to be non-empty, but at the same time allow fake "-"
which effectively means "no vmlinux". Make it optional.
Uncovered PCs were handled very badly:
we added PCs from the same function multiple times
and did not remove covered PCs. As the result total
number of uncovered PCs was terrific.
Fix that.
Log is a simple wrapper around std log package.
It is meant to solve 2 main problems:
1. Logging from non-main packages (mainly, vm/* packages).
Currently they can either always log or not log at all.
But they can't respect program verbosity setting.
Log package allows all packages to use the same verbosity setting.
2. Exposing recent logs in html UI.
Namely we want to tee logs to console and html UI.
When executors send coverage data to the manager, they clamp the addresses
of covered blocks to 32 bits. Manager uses RestorePC() to restore the original
addresses.
Previously, RestorePC() assumed that the upper 4 bytes of a kernel code
address were 0xffffffff, which is not so on Android.
Instead we now parse `readelf -SW vmlinux` output to obtain the upper bytes of
PROGBITS sections VMAs in the case those VMAs are non-zero. We assume that
the upper 4 bytes are the same for every section.
Remove master process entirely, it is not useful in its current form.
We first need to understand what we want from it, and them re-implement it.
Prefix all binaries with syz- to avoid name clashes.
