[PATCH] dtrace crashes when trying to trace fbt probes

[Paul Ambrose]

Hi, Ryan, I came across the similar problem on 8-stable when I run
# dtrace -lv
the panic message says:
page fault just happened at fbt.c
........................................................................
    if (*lc.ctfoffp == NULL) {       // page fault
        /*
         * Initialise the CTF object and function symindx to
         * byte offset array.
         */
        if (fbt_ctfoff_init(ctl, &lc) != 0)
            return;

        /* Initialise the CTF type to byte offset array. */
        if (fbt_typoff_init(&lc) != 0)
            return;
    }
........................................................................

And I came across the similar problem on 9-current only once, but when I
recompile the kernel,
it does not reproduce. I will try your patch on 8-stable, but could you tell
me  where did you meet
the problem, and what is your module without CTF data?