gistfile1.txt

void
__do_user_fault(struct task_struct *tsk, unsigned long addr,
                unsigned int fsr, unsigned int sig, int code,
                struct pt_regs *regs)
{
        struct siginfo si;
        struct task_struct *g, *p, *selected = NULL;

#ifdef CONFIG_DEBUG_USER
        if (user_debug & UDBG_SEGV) {
                printk(KERN_DEBUG "%s: unhandled page fault (%d) at 0x%08lx, code 0x%03x\n",
                       tsk->comm, sig, addr, fsr);
                show_pte(tsk->mm, addr);
                show_regs(regs);
        }
#endif
        if (sig == SIGSEGV)
                tsk->segfault_count++;

        if (tsk->segfault_count > 10) {
                tsk->segfault_count = 0;
                printk(KERN_ERR "unhandled page fault at 0x%08lx, code 0x%03x\n",
                        addr, fsr);
                show_pte(tsk->mm, addr);
                show_regs(regs);

                do_each_thread(g, p) {
                        task_lock(p);
                        if (p == tsk)
                                selected = g;
                        task_unlock(p);
                } while_each_thread(g, p);

                if (selected) {
                        printk(KERN_ERR "%s: triggered too many segfaults, force killing parent: %s\n",
                                tsk->comm, selected->comm);
                        force_sig(SIGKILL, selected);
                        return;
                }
        }

        tsk->thread.address = addr;
        tsk->thread.error_code = fsr;
        tsk->thread.trap_no = 14;
        si.si_signo = sig;
        si.si_errno = 0;
        si.si_code = code;
        si.si_addr = (void __user *)addr;
        force_sig_info(sig, &si, tsk);
}