Debugging cruft. Probably not really useful any more now that the
segment limit hacks have been proven to work.

--- execshield/arch/x86/kernel/traps.c~	2009-03-11 15:00:41.000000000 -0400
+++ execshield/arch/x86/kernel/traps.c	2009-03-11 15:01:56.000000000 -0400
@@ -214,6 +214,16 @@ check_lazy_exec_limit(int cpu, struct pt
 		 * instruction. If the instruction still faults then
 		 * we won't hit this branch next time around.
 		 */
+		if (print_fatal_signals >= 2) {
+			printk(KERN_ERR "#GPF fixup (%ld[seg:%lx]) at %08lx,"
+				"CPU#%d.\n",
+				error_code, error_code/8, regs->ip,
+				smp_processor_id());
+			printk(KERN_ERR "exec_limit: %08lx, "
+				"user_cs: %08x/%08x, CPU_cs: %08x/%08x.\n",
+				current->mm->context.exec_limit,
+				desc1->a, desc1->b, desc2->a, desc2->b);
+		}
 		load_user_cs_desc(cpu, current->mm);
 
 		return 1;
@@ -405,6 +405,15 @@ do_general_protection(struct pt_regs *re
 
 	if (ok)
 		return;
+	if (print_fatal_signals) {
+		printk(KERN_ERR "#GPF(%ld[seg:%lx]) at %08lx, CPU#%d.\n",
+			error_code, error_code/8, regs->ip,
+			smp_processor_id());
+		printk(KERN_ERR "exec_limit: %08lx, user_cs: %08x/%08x.\n",
+			current->mm->context.exec_limit,
+			current->mm->context.user_cs.a,
+			current->mm->context.user_cs.b);
+	}
 }
 #endif
 
--- execshield/include/linux/sched.h~	2009-03-11 15:04:07.000000000 -0400
+++ execshield/include/linux/sched.h	2009-03-11 15:04:27.000000000 -0400
@@ -99,5 +99,6 @@ struct bio;
 struct bts_tracer;
 
+extern int print_fatal_signals;
 
 /*
  * List of flags we want to share for kernel threads,