A number of further possible improvements were identified when putting
together the patches for these XSAs; some therefore already have acks or
alike. Some of these may want considering to take for 4.22.

Many of the patches here are largely independent, but the last one
(following on to XSA-491, while all others are XSA-492 related) really
depends on the 2nd to last one. Or else bigger changes would be
necessary there.

v2, besides addressing review comments, has one new patch and includes
one patch which was previously submitted independently. See individual
patches for details on changes.

1: sched: introduce specialization of "running only" vcpu_runstate_get()
2: domctl: handle XEN_DOMCTL_getvcpuinfo without acquiring domctl lock
3: domctl: move early special casing of XEN_DOMCTL_shadow_op
4: domctl: restrict permission check for XEN_DOMCTL_memory_mapping's remove form
5: domctl: correct return value of XEN_DOMCTL_[gs]etvcpuaffinity
6: x86/domctl: don't imply I/O port permissions from I/O port mapping
7: x86/HVM: more checking for XEN_DOMCTL_ioport_mapping

Jan