Too many CFI instuctions

[maliubiao]

Hi,  I am trying to capture some stack data of python runtime and draw
the function graph somewhere.
systemtap script:
global s;

probe process("../python").function("*") {
    s[sprint_ubacktrace()] <<< 1;
}

probe end {
    foreach ([stack] in s+) {
        printf("%s\\n\\n", stack);
    }
}

After a signal python command "1+1",   The python runtime crashed with
segment fault, The message in systemtap is "Too many CFI instuctions,
Too many pending (warning) messages".   What's CFI instuction ?  Why
segment fault?