From: Andrew Cooper <andrew.cooper3@citrix.com>
Date: Tue, 4 Nov 2014 11:39:43 +0000 (+0000)
Subject: cirrus_vga: default all I/O port reads to 0xff
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=c615d81a3c0fca9ca4706f6505cc032c737cf0c9;p=people%2Fliuw%2Flibxenctrl-split%2Fqemu-xen-traditional.git

cirrus_vga: default all I/O port reads to 0xff

Some error paths in vga_ioport_read() would return undefined values.
Always default the result to 0xff.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
---

diff --git a/hw/cirrus_vga.c b/hw/cirrus_vga.c
index a26b0517..11ce212d 100644
--- a/hw/cirrus_vga.c
+++ b/hw/cirrus_vga.c
@@ -2674,7 +2674,7 @@ static void cirrus_update_memory_access(CirrusVGAState *s)
 static uint32_t vga_ioport_read(void *opaque, uint32_t addr)
 {
     CirrusVGAState *s = opaque;
-    int val, index;
+    int val = 0xff, index;
 
     /* check port range access depending on color/monochrome mode */
     if ((addr >= 0x3b0 && addr <= 0x3bf && (s->msr & MSR_COLOR_EMULATION))