Compile-time stack validation

I think it would need to dump the whole stack to do that, which could easily include sensitive information. The problem is that even figuring out where the stack frames *are* in the stack requires really quite a lot of the DWARF.

The right approach is probably to deduplicate the DWARF at compile time, write it out in a much more compact form suitable for the stacktracer, and link it into the kernel, perhaps compressed. This is what DTrace does for kernel type resolution (though obviously it is doing this to a different bit of the DWARF, the type info, which needs more deduplication but doesn't need any kernel runtime support at all, since the userspace tool does all the necessary processing: I don't think this is possible for stack backtraces, as I note above).