From patchwork Mon May 9 15:48:19 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 94783 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id C6EADB6F1A for ; Tue, 10 May 2011 01:48:34 +1000 (EST) Received: from localhost ([::1]:47308 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QJShE-0004ea-7b for incoming@patchwork.ozlabs.org; Mon, 09 May 2011 11:48:32 -0400 Received: from eggs.gnu.org ([140.186.70.92]:39255) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QJSh6-0004eK-NU for qemu-devel@nongnu.org; Mon, 09 May 2011 11:48:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QJSh4-0003Mp-M9 for qemu-devel@nongnu.org; Mon, 09 May 2011 11:48:24 -0400 Received: from david.siemens.de ([192.35.17.14]:33335) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QJSh4-0003KU-DX for qemu-devel@nongnu.org; Mon, 09 May 2011 11:48:22 -0400 Received: from mail1.siemens.de (localhost [127.0.0.1]) by david.siemens.de (8.13.6/8.13.6) with ESMTP id p49FmKdE026893; Mon, 9 May 2011 17:48:20 +0200 Received: from mchn199C.mchp.siemens.de ([139.25.109.49]) by mail1.siemens.de (8.13.6/8.13.6) with ESMTP id p49FmJ6N001816; Mon, 9 May 2011 17:48:19 +0200 Message-ID: <4DC80CC3.2030807@siemens.com> Date: Mon, 09 May 2011 17:48:19 +0200 From: Jan Kiszka User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); de; rv:1.8.1.12) Gecko/20080226 SUSE/2.0.0.12-1.1 Thunderbird/2.0.0.12 Mnenhy/0.7.5.666 MIME-Version: 1.0 To: Alexander Graf , Kevin Wolf X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 192.35.17.14 Cc: qemu-devel Subject: [Qemu-devel] [PATCH] ahci: Fix crashes on duplicate BH registration X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org If ahci_dma_set_inactive is called a while there is still a pending BH from a previous run, we will crash on the second run of ahci_check_cmd_bh as it overwrites AHCIDevice::check_bh. Avoid this broken and redundant duplicate registration. Signed-off-by: Jan Kiszka --- hw/ide/ahci.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c index c6e0c77..744d19d 100644 --- a/hw/ide/ahci.c +++ b/hw/ide/ahci.c @@ -1066,9 +1066,11 @@ static int ahci_dma_set_inactive(IDEDMA *dma) ad->dma_cb = NULL; - /* maybe we still have something to process, check later */ - ad->check_bh = qemu_bh_new(ahci_check_cmd_bh, ad); - qemu_bh_schedule(ad->check_bh); + if (!ad->check_bh) { + /* maybe we still have something to process, check later */ + ad->check_bh = qemu_bh_new(ahci_check_cmd_bh, ad); + qemu_bh_schedule(ad->check_bh); + } return 0; }