From: Ian Jackson <ian.jackson@eu.citrix.com>
Date: Tue, 24 Mar 2009 18:12:39 +0000 (+0000)
Subject: cirrus: Do not clear vram area to 0xff when not yet allocated.
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=545882583159e9cc53cde5965277967092459f37;p=xenclient%2Fioemu.git

cirrus: Do not clear vram area to 0xff when not yet allocated.

When restoring, the vram data pointer is not valid until (depending on
the version of the savefile) the guest has informed us what memory to
use.  Thus vram_ptr may be NULL.  In this patch we avoid attempting to
clear the video ram in this case.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
---

diff --git a/hw/cirrus_vga.c b/hw/cirrus_vga.c
index 6149a0f9..28b02391 100644
--- a/hw/cirrus_vga.c
+++ b/hw/cirrus_vga.c
@@ -3194,9 +3194,10 @@ static void cirrus_reset(void *opaque)
     }
     s->cr[0x27] = s->device_id;
 
-    /* Win2K seems to assume that the pattern buffer is at 0xff
-       initially ! */
-    memset(s->vram_ptr, 0xff, s->real_vram_size);
+    if (s->vram_ptr)
+        /* Win2K seems to assume that the pattern buffer is at 0xff
+           initially ! */
+        memset(s->vram_ptr, 0xff, s->real_vram_size);
 
     s->cirrus_hidden_dac_lockindex = 5;
     s->cirrus_hidden_dac_data = 0;