qemu/0039-console-Fix-segfault-on-screendump-without-VGA-adap.patch

From 2b0fc5def570362c27ce526b8a08529a6ae22362 Mon Sep 17 00:00:00 2001
From: Alexander Graf <agraf@suse.de>
Date: Fri, 18 Nov 2011 16:41:59 +0100
Subject: [PATCH] console: Fix segfault on screendump without VGA adapter

When trying to create a screen dump without having any VGA adapter
inside the guest, QEMU segfaults.

This is because it's trying to switch back to the "previous" screen
it was on before dumping the VGA screen. Unfortunately, in my case
there simply is no previous screen so it accesses a NULL pointer.

Fix it by checking if previous_active_console is actually available.

This is 1.0 material.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 console.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/console.c b/console.c
index f6fe441..ed6a653 100644
--- a/console.c
+++ b/console.c
@@ -186,7 +186,9 @@ void vga_hw_screen_dump(const char *filename)
         consoles[0]->hw_screen_dump(consoles[0]->hw, filename);
     }
 
-    console_select(previous_active_console->index);
+    if (previous_active_console) {
+        console_select(previous_active_console->index);
+    }
 }
 
 void vga_hw_text_update(console_ch_t *chardata)
-- 
1.6.0.2