From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752012Ab2IPJnB (ORCPT ); Sun, 16 Sep 2012 05:43:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:63023 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751208Ab2IPJnA (ORCPT ); Sun, 16 Sep 2012 05:43:00 -0400 Date: Sun, 16 Sep 2012 12:44:27 +0300 From: "Michael S. Tsirkin" To: Rusty Russell Cc: Sjur =?iso-8859-1?Q?Br=E6ndeland?= , Amit Shah , linux-kernel@vger.kernel.org, Ohad Ben-Cohen , Linus Walleij , virtualization@lists.linux-foundation.org Subject: [PATCH repost] virtio: don't crash when device is buggy Message-ID: <20120916094427.GA24075@redhat.com> References: <1346680277-5887-1-git-send-email-sjur.brandeland@stericsson.com> <20120903143018.GA5353@redhat.com> <20120903202737.GD6181@redhat.com> <20120904135022.GI9805@redhat.com> <20120904185541.GB3602@redhat.com> <87k3w7j49i.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87k3w7j49i.fsf@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Because of a sanity check in virtio_dev_remove, a buggy device can crash kernel. And in case of rproc it's userspace so it's not a good idea. We are unloading a driver so how bad can it be? Be less aggressive in handling this error: if it's a driver bug, warning once should be enough. Signed-off-by: Michael S. Tsirkin -- 3.6 material? diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index c3b3f7f..1e8659c 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -159,7 +159,7 @@ static int virtio_dev_remove(struct device *_d) drv->remove(dev); /* Driver should have reset device. */ - BUG_ON(dev->config->get_status(dev)); + WARN_ON_ONCE(dev->config->get_status(dev)); /* Acknowledge the device's existence again. */ add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE); -- MST