* 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. :() -- Dong Jia Shi
