[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] Using PCI config space to indicate config location
From: |
Rusty Russell |
Subject: |
Re: [Qemu-devel] Using PCI config space to indicate config location |
Date: |
Wed, 17 Oct 2012 00:22:25 +1030 |
User-agent: |
Notmuch/0.13.2 (http://notmuchmail.org) Emacs/23.3.1 (i686-pc-linux-gnu) |
"Michael S. Tsirkin" <address@hidden> writes:
> On Tue, Oct 16, 2012 at 11:45:41PM +1030, Rusty Russell wrote:
>> "Michael S. Tsirkin" <address@hidden> writes:
>> I was assuming the implementation would keep two complete copies of the
>> config space: writes go to the scratch version, which gets copied to the
>> master version upon latch write.
>
> Yes but config space has some host modifiable registers too.
> So host needs to be careful to avoid overwriting these.
>
> If accesses have side effects that of course breaks too ...
Yes.
>
>> But I do wonder if we should just skip this for now, since we don't
>> have any immediate need.
>>
>> Cheers,
>> Rusty.
>
> MAC setting from guest needs this right now, no?
Ah, I missed that in my table:
Driver Config Device changes Driver writes... after init?
net Y Y N N
block Y Y Y Y
console Y Y N N
rng N N N N
balloon Y Y Y Y
scsi Y N Y N
9p Y N N N
First line should be:
net Y Y Y N
So we could add a new cvq command (eg. #define VIRTIO_NET_CTRL_MAC_SET
1) and a VIRTIO_NET_F_CVQ_MAC_SET feature. Or go ahead with the
latching scheme (which doesn't really help other busses).
Cheers,
Rusty.
- Re: [Qemu-devel] Using PCI config space to indicate config location, (continued)
- Re: [Qemu-devel] Using PCI config space to indicate config location, Michael S. Tsirkin, 2012/10/10
- Re: [Qemu-devel] Using PCI config space to indicate config location, Rusty Russell, 2012/10/10
- Re: [Qemu-devel] Using PCI config space to indicate config location, Michael S. Tsirkin, 2012/10/11
- Re: [Qemu-devel] Using PCI config space to indicate config location, Rusty Russell, 2012/10/11
- Re: [Qemu-devel] Using PCI config space to indicate config location, Michael S. Tsirkin, 2012/10/12
- Re: [Qemu-devel] Using PCI config space to indicate config location, Rusty Russell, 2012/10/12
- Re: [Qemu-devel] Using PCI config space to indicate config location, Michael S. Tsirkin, 2012/10/12
- Re: [Qemu-devel] Using PCI config space to indicate config location, Rusty Russell, 2012/10/16
- Re: [Qemu-devel] Using PCI config space to indicate config location, Michael S. Tsirkin, 2012/10/16
- Re: [Qemu-devel] Using PCI config space to indicate config location,
Rusty Russell <=
Re: [Qemu-devel] Proposal for virtio standardization., Cornelia Huck, 2012/10/09