Re: [Qemu-devel] [PATCH] virtio-spec: clarify ro/rw bits and updating rule of virtio-net status field

2012-03-22 Thread Jason Wang
On 03/22/2012 12:30 PM, Rusty Russell wrote: On Wed, 21 Mar 2012 08:37:46 +0200, "Michael S. Tsirkin" wrote: Ah. Right, we need to trap for host to clear the bit. OK, so let's make the bit RO, and add VIRTIO_NET_CTRL_ANNOUNCED to acknowledge that we've seen VIRTIO_NET_S_ANNOUNCE using the cont

Re: [Qemu-devel] [PATCH] virtio-spec: clarify ro/rw bits and updating rule of virtio-net status field

2012-03-22 Thread Rusty Russell
On Wed, 21 Mar 2012 08:37:46 +0200, "Michael S. Tsirkin" wrote: > Ah. Right, we need to trap for host to clear the bit. > OK, so let's make the bit RO, and add > VIRTIO_NET_CTRL_ANNOUNCED to acknowledge that we've > seen VIRTIO_NET_S_ANNOUNCE using the control VQ? Thanks, that's nice. Guest sho

Re: [Qemu-devel] [PATCH] virtio-spec: clarify ro/rw bits and updating rule of virtio-net status field

2012-03-20 Thread Michael S. Tsirkin
On Wed, Mar 21, 2012 at 10:10:52AM +1030, Rusty Russell wrote: > On Wed, 21 Mar 2012 00:48:05 +0200, "Michael S. Tsirkin" > wrote: > > On Tue, Mar 20, 2012 at 09:35:18PM +1030, Rusty Russell wrote: > > > On Tue, 20 Mar 2012 14:20:21 +0800, Jason Wang > > > wrote: > > > > This patch clarifies VI

Re: [Qemu-devel] [PATCH] virtio-spec: clarify ro/rw bits and updating rule of virtio-net status field

2012-03-20 Thread Rusty Russell
On Wed, 21 Mar 2012 00:48:05 +0200, "Michael S. Tsirkin" wrote: > On Tue, Mar 20, 2012 at 09:35:18PM +1030, Rusty Russell wrote: > > On Tue, 20 Mar 2012 14:20:21 +0800, Jason Wang wrote: > > > This patch clarifies VIRTIO_NET_S_LINK_UP as a read-only bit and > > > VIRTIO_NET_S_ANNOUNCE as a read-

Re: [Qemu-devel] [PATCH] virtio-spec: clarify ro/rw bits and updating rule of virtio-net status field

2012-03-20 Thread Michael S. Tsirkin
On Tue, Mar 20, 2012 at 09:35:18PM +1030, Rusty Russell wrote: > On Tue, 20 Mar 2012 14:20:21 +0800, Jason Wang wrote: > > This patch clarifies VIRTIO_NET_S_LINK_UP as a read-only bit and > > VIRTIO_NET_S_ANNOUNCE as a read-writable bit. Also introduce the write 1 to > > clear semantics for all re

Re: [Qemu-devel] [PATCH] virtio-spec: clarify ro/rw bits and updating rule of virtio-net status field

2012-03-20 Thread Rusty Russell
On Tue, 20 Mar 2012 14:20:21 +0800, Jason Wang wrote: > This patch clarifies VIRTIO_NET_S_LINK_UP as a read-only bit and > VIRTIO_NET_S_ANNOUNCE as a read-writable bit. Also introduce the write 1 to > clear semantics for all read-writable bits of config status field. This could > help to reduce th

[Qemu-devel] [PATCH] virtio-spec: clarify ro/rw bits and updating rule of virtio-net status field

2012-03-19 Thread Jason Wang
This patch clarifies VIRTIO_NET_S_LINK_UP as a read-only bit and VIRTIO_NET_S_ANNOUNCE as a read-writable bit. Also introduce the write 1 to clear semantics for all read-writable bits of config status field. This could help to reduce the config status field updating race between host and guest and