From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761187AbZEFUjW (ORCPT ); Wed, 6 May 2009 16:39:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760714AbZEFUiq (ORCPT ); Wed, 6 May 2009 16:38:46 -0400 Received: from kroah.org ([198.145.64.141]:33797 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760922AbZEFUip (ORCPT ); Wed, 6 May 2009 16:38:45 -0400 X-Mailbox-Line: From greg@blue.kroah.org Wed May 6 13:31:28 2009 Message-Id: <20090506203128.070109983@blue.kroah.org> User-Agent: quilt/0.48-1 Date: Wed, 06 May 2009 13:30:12 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, jejb@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Christian Borntraeger , Rusty Russell , Chris Wright , Greg Kroah-Hartman Subject: [patch 02/18] virtio-rng: Remove false BUG for spurious callbacks References: <20090506203010.615363711@blue.kroah.org> Content-Disposition: inline; filename=virtio-rng-remove-false-bug-for-spurious-callbacks.patch In-Reply-To: <20090506203353.GA14624@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Christian Borntraeger upstream commit: e5b89542ea18020961882228c26db3ba87f6e608 The virtio-rng drivers checks for spurious callbacks. Since callbacks can be implemented via shared interrupts (e.g. PCI) this could lead to guest kernel oopses with lots of virtio devices. Signed-off-by: Christian Borntraeger Cc: Rusty Russell Cc: stable@kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Chris Wright Signed-off-by: Greg Kroah-Hartman --- drivers/char/hw_random/virtio-rng.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -37,9 +37,9 @@ static void random_recv_done(struct virt { int len; - /* We never get spurious callbacks. */ + /* We can get spurious callbacks, e.g. shared IRQs + virtio_pci. */ if (!vq->vq_ops->get_buf(vq, &len)) - BUG(); + return; data_left = len / sizeof(random_data[0]); complete(&have_data);