On 09/08/2017 04:01 AM, Dong Jia Shi wrote: > * Cornelia Huck <coh...@redhat.com> [2017-09-07 12:52:20 +0200]: > >> On Thu, 7 Sep 2017 12:21:50 +0200 >> Halil Pasic <pa...@linux.vnet.ibm.com> wrote: >> >>> On 09/07/2017 10:08 AM, Cornelia Huck wrote: >>>> On Thu, 7 Sep 2017 15:31:09 +0800 >>>> Dong Jia Shi <bjsdj...@linux.vnet.ibm.com> wrote: >> >>>>> I'm thinking of a method these days: >>>>> Could passing through an fully emulated ccw device (e.g. 3270), or a >>>>> virtio ccw device, in the level 1 kvm guest to a level 2 guest be a test >>>>> method for this? >>>>> >>>>> All of the CCWs will be translated to IDAL CCWs by vfio-ccw in the level >>>>> 1 guest (which is the level 2 kvm host) and issued to the level 1 kvm >>>>> host. So, those IDALs will eventually be handled by the emulated device, >>>>> or the virtio ccw device, on the level 1 kvm host... >>>>> >>>>> Some days ago, one of my colleague tried the emulated 3270 passing >>>>> through. She stucked with the problem that the level 1 kvm host handling >>>>> a senseid IDAL ccw as a Direct ccw. >>>>> >>>>> Maybe I could try to pass through a virtio ccw device. I don't think of >>>>> any obvious problem that would lead to fail. Any comment? >>>>> >>>> >>>> That actually looks like a good thing to try! Cool idea. >>>> >>> >>> I'm afraid that it would not work without some extra work. >>> AFAIR Connie we said that the 3270 does not use any IDA, so >>> I did not touch the 3270 emulation code in QEMU. To make >>> the scenario viable one should convert the 3270 emulation >>> to ccw data stream (unless the original implementation >>> already took care of IDA, which I doubt). >> >> But the vfio-ccw code uses idals... no need to touch the 3270 emulation. >> > What Halil pointed out is that the ccw_cb implementation of 3270 > emulation does not take care of IDALs. This is true. > > I can also do that right after this series, if Halil agrees. > (The 3270 emulation authors are busy of other stuff these days. :()
Generally, yes I agree. If it's trivial I will probably do it myself for v2. I need to do a v2 anyway. Halil
