From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:54025) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RlOYz-0003OR-GY for qemu-devel@nongnu.org; Thu, 12 Jan 2012 12:35:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RlOYs-0003gz-ST for qemu-devel@nongnu.org; Thu, 12 Jan 2012 12:35:45 -0500 From: Alexander Graf Date: Thu, 12 Jan 2012 18:35:25 +0100 Message-Id: <1326389731-1694-2-git-send-email-agraf@suse.de> In-Reply-To: <1326389731-1694-1-git-send-email-agraf@suse.de> References: <1326389731-1694-1-git-send-email-agraf@suse.de> Subject: [Qemu-devel] [PATCH 1/7] console: Fix segfault on screendump without VGA adapter List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel Developers Cc: jmforbes@linuxtx.org, qemu-stable@nongnu.org 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 --- 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