|
From: | Alexander Graf |
Subject: | Re: [Qemu-devel] [PATCH 2/4] s390-virtio-bus: move common virtio properties to virtio s390 device class |
Date: | Tue, 17 Jun 2014 14:57:16 +0200 |
User-agent: | Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 |
On 17.06.14 14:56, Cornelia Huck wrote:
On Tue, 17 Jun 2014 14:06:25 +0200 Alexander Graf <address@hidden> wrote:On 17.06.14 14:04, Cornelia Huck wrote:On Tue, 17 Jun 2014 18:45:09 +0800 Ming Lei <address@hidden> wrote:On Tue, Jun 17, 2014 at 6:40 PM, Ming Lei <address@hidden> wrote:On Tue, Jun 17, 2014 at 6:25 PM, Cornelia Huck <address@hidden> wrote:On Tue, 17 Jun 2014 18:15:39 +0800 Ming Lei <address@hidden> wrote:On Tue, Jun 17, 2014 at 4:46 PM, Cornelia Huck <address@hidden> wrote:Looks like s390 virtio-blk never enables the two common features, is there any reason the two features can't be supported by s390?Indirect descriptors are fine. event_idx will not work IIUC because we always need to do a sync before we see changes, and this needs an interrupt to trigger.Sounds like the old s390 isn't cache coherent? Because you mean write in one side can only be observed from another side with an explicit notification or interrupt. On arm/arm64, we didn't see any problem with event_idx.But you probably have the queues in guest memory, as on other transports (including virtio-ccw)? The old s390-virtio transport keeps the devices and their virtqueues in a memory area behind the guest memory - the guest does not see that memory directly, but a sync has to be performed to see virtqueue movement (see s390_virtio_device_sync()).OK, it looks like a real physical device, :-) I will keep s390-virtio as it is, thanks for your explanation.BTW, do you want me to add DEFINE_VIRTIO_COMMON_FEATURES() to s390_virtio_net_properties and s390_virtio_scsi_properties since I remove them from their default properties?It might be better to remove them for good :) Nobody has probably tried to use them for some time... I just start a very minimal guest with a virtio-console and a virtio-blk device. Don't know whether Alex has a more advanced setup at hand?It's the only target that works with TCG, no?Yup. Do you have a test setup with net, scsi, ...? I usually test networking (for example) only via a libvirt setup, which will only work with virtio-ccw.
I don't regularly test it, but OBS uses that target for example. Alex
[Prev in Thread] | Current Thread | [Next in Thread] |