Handle vDSO frames correctly on i686

[mmilata]

#include <stdio.h>
#include <stdlib.h>

#include <poll.h>

int main(int argc, char *argv[])
{
    struct pollfd pfd = {
        .fd = 0,
        .events = POLLIN,
        .revents = 0
    };

    return poll(&pfd, 1, 1000000);
}

eu-stack seems to get it right.

Related to #127.

[jankratochvil]

Is this related to d06baf1? It works with eu-stack which does not contain any explicit dwfl_linux_proc_maps_report() call. Why does satyr need it? Is there a reproducer/testcase?

[mmilata]

@jankratochvil I believe this affected version of satyr which did not yet use the dwfl_linux_proc_maps_report call (which we probably won't use: #175). It probably was caused by bug in or bad usage of elfutils: https://bugzilla.redhat.com/show_bug.cgi?id=1129756