Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752118AbaK3Poj (ORCPT ); Sun, 30 Nov 2014 10:44:39 -0500 Received: from mail-la0-f41.google.com ([209.85.215.41]:35118 "EHLO mail-la0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751898AbaK3Poh (ORCPT ); Sun, 30 Nov 2014 10:44:37 -0500 Message-ID: <547B3B61.3090801@cogentembedded.com> Date: Sun, 30 Nov 2014 18:44:33 +0300 From: Sergei Shtylyov User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: "Michael S. Tsirkin" , linux-kernel@vger.kernel.org CC: David Miller , cornelia.huck@de.ibm.com, rusty@au1.ibm.com, nab@linux-iscsi.org, pbonzini@redhat.com, thuth@linux.vnet.ibm.com, dahi@linux.vnet.ibm.com, Jason Wang , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Subject: Re: [PATCH v7 28/46] vhost: make features 64 bit References: <1417359787-10138-1-git-send-email-mst@redhat.com> <1417359787-10138-29-git-send-email-mst@redhat.com> In-Reply-To: <1417359787-10138-29-git-send-email-mst@redhat.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello. On 11/30/2014 6:11 PM, Michael S. Tsirkin wrote: > We need to use bit 32 for virtio 1.0 > Signed-off-by: Michael S. Tsirkin > Reviewed-by: Jason Wang > --- > drivers/vhost/vhost.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h > index 3eda654..c624b09 100644 > --- a/drivers/vhost/vhost.h > +++ b/drivers/vhost/vhost.h > @@ -106,7 +106,7 @@ struct vhost_virtqueue { > /* Protected by virtqueue mutex. */ > struct vhost_memory *memory; > void *private_data; > - unsigned acked_features; > + u64 acked_features; > /* Log write descriptors */ > void __user *log_base; > struct vhost_log *log; > @@ -174,6 +174,6 @@ enum { > > static inline int vhost_has_feature(struct vhost_virtqueue *vq, int bit) > { > - return vq->acked_features & (1 << bit); > + return vq->acked_features & (1ULL << bit); Erm, wouldn't the high word be just dropped when returning *int*? I think you need !!(vq->acked_features & (1ULL << bit)). [...] WBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/