kprobes/x86-32: Move irq-exit functions to kprobes section

Move irq-exit functions to .kprobes.text section to protect against
kprobes recursion.

When I ran kprobe stress test on x86-32, I found below symbols
cause unrecoverable recursive probing:

	ret_from_exception
	ret_from_intr
	check_userspace
	restore_all
	restore_all_notrace
	restore_nocheck
	irq_return

And also, I found some interrupt/exception entry points that
cause similar problems.

This patch moves those symbols (including their container functions)
to .kprobes.text section to prevent any kprobes probing.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20090908164755.24050.81182.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 3267d90..00d01b0 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -91,6 +91,8 @@
 static struct kprobe_blackpoint kprobe_blacklist[] = {
 	{"preempt_schedule",},
 	{"native_get_debugreg",},
+	{"irq_entries_start",},
+	{"common_interrupt",},
 	{NULL}    /* Terminator */
 };