Re: [libvirt] [RFC v2 2/3] nvdimm: update qemu command-line generating for NVDIMM memory

On Thu, Nov 29, 2018 at 12:08:58 +0800, Luyao Zhong wrote: [...] The properties of memory-backed-file are automatically detected declaratively by adding the property and required flag into the virQEMUCapsObjectPropsMemoryBackendFile array. Device properties have a similar approach but we don't have anything for nvdimm yet. You'll need to add nvdimm into virQEMUCapsDeviceProps[] with appropriate arrays for detecting the features. Note that the above will trigger test failures in the capabilities test as it will add an additional command into the query procedure. You'll need to regenerate/fix the test data for any version of qemu we have in tests/qemucapabilitiesdata/caps_* which supports NVDIMM. Note that only relevant changes should be included in such regeneration, e.g. if you have a different CPU than the original files, the CPU related data should not be changed. Regeneratin of the *.replies files can be done with tests/qemucapsprobe tool, or if you opt to add the relevant sections manually, you can use tests/qemucapsfixreplies to fix the numbering of the commands. I don't really know when that field was introduced. If it was there from the time NVDIMM was added into qemu, no capability bit is necessary. Also in some cases, when the feture is really niche and not expected to be widely used (as in fact the whole nvdimm stuff is) we can skip that and just rely on errors from qemu.