On 04.12.2017 18:53, Cornelia Huck wrote: > On Mon, 4 Dec 2017 18:34:36 +0100 > David Hildenbrand <da...@redhat.com> wrote: > >> On 04.12.2017 18:22, Cornelia Huck wrote: >>> On Mon, 4 Dec 2017 13:55:05 +0100 >>> David Hildenbrand <da...@redhat.com> wrote: >>> >>>> We somehow missed that, new kernels require it. >>> >>> Why _new_ kernels? I think we have unconditionally issued stcrw since >>> back in 2.2? >> >> Okay, the problem is then rather related to my setup. No ccw devices -> >> no stcrw. >> >> How could we ever add ccw devices to a TCG guest then? > > Hotplug never worked before your patches. Coldplug does not create > machine checks and thus does not trigger the guest to do STCRW. (Only > STSCH, in keeping with "all channel I/O acronyms look the same".) >
But booting Fedora 26/27 without any involved hotplugs (therefore machine checks) triggers a STCRW. That's how I originally found it. (I started playing with machine checks after I had fedora 26/27 running) -- Thanks, David / dhildenb
