From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753787Ab0BWRB5 (ORCPT ); Tue, 23 Feb 2010 12:01:57 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48609 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753688Ab0BWRBz (ORCPT ); Tue, 23 Feb 2010 12:01:55 -0500 Date: Tue, 23 Feb 2010 18:57:58 +0200 From: "Michael S. Tsirkin" To: Rusty Russell , kvm@vger.kernel.org, virtualization@lists.osdl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, David Miller , markmc@redhat.com, gleb@redhat.com, herbert.xu@redhat.com, quintela@redhat.com, dlaor@redhat.com, avi@redhat.com Subject: [PATCH 3/3] vhost: fix get_user_pages_fast error handling Message-ID: <82ba8c97ce55dd4bf9972ad755961cd14e6a0938.1266943453.git.mst@redhat.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Mutt-Fcc: =sent User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org get_user_pages_fast returns number of pages on success, negative value on failure, but never 0. Fix vhost code to match this logic. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index d4f8fdf..d003504 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -646,8 +646,9 @@ static int set_bit_to_user(int nr, void __user *addr) int bit = nr + (log % PAGE_SIZE) * 8; int r; r = get_user_pages_fast(log, 1, 1, &page); - if (r) + if (r < 0) return r; + BUG_ON(r != 1); base = kmap_atomic(page, KM_USER0); set_bit(bit, base); kunmap_atomic(base, KM_USER0); -- 1.7.0.18.g0d53a5