x86: make PioBus return BadAddress errors

Stop setting the use_default_range flag in PioBus in order to
have random bad addresses result in a BadAddress response and
not a gem5 fatal error.  This is necessary in Ruby as Ruby is
connected directly to PioBus, so misspeculated addresses will
be sent there directly.  For the classic memory system, this
change has no effect, as bad addresses are caught by the
memory bus before being sent to the PioBus.

This work was done while Binh was an intern at AMD Research.

diff --git a/src/dev/x86/Pc.py b/src/dev/x86/Pc.py
index bd8b2ad98635af8948fa489de04d7afb449f5212..1f1f3ca89ba3a345f277583ed85d6800e4ecccc7 100644 (file)
--- a/src/dev/x86/Pc.py
+++ b/src/dev/x86/Pc.py
@@ -79,4 +79,3 @@ class Pc(Platform):
         self.fake_com_4.pio = bus.master
         self.fake_floppy.pio = bus.master
         self.pciconfig.pio = bus.default
-        bus.use_default_range = True