On Mon, Jan 03, 2022 at 16:56:32 +0100, Ján Tomko wrote: > On a Monday in 2022, Peter Krempa wrote: > > As a workaround for users using 'libvirt-7.9' and 'libvirt-7.10' with > > 'qemu-6.2' who wish to use device hot-unplug we are going to be > > suggesting to filter out the 'device.json' qemu capability via either > > the global 'qemu.conf' config: > > > > capability_filters = [ "device.json" ] > > > > or the per-VM XML capability override: > > > > <domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'> > > > > [...] > > > > <qemu:capabilities> > > <qemu:del capability='device.json'/> > > </qemu:capabilities> > > </domain> > > > > Doing this poisons the capability name 'device.json' for any further > > use, so to ensure that we can re-add JSON usage for -device also for > > users which filtered it out originally once it's fixed in qemu we need > > to condemn the old name and add a new one. > > > > To achieve this the old capability is renamed to > > 'X_QEMU_CAPS_DEVICE_JSON_BROKEN' and a new capability > > 'QEMU_CAPS_DEVICE_JSON' is mapped to 'device.json-fixed'. For now we > > I am not a fan of the new string but we can change it later once it's > clear how to probe for this in QEMU. In fact, I can leave this commit out for now, or replace it by just noting in qemu_capabilities.h that the flag name was poisoned by recomending users to filter it out and a new one must be picked when re-instating this feature.
