Re: [libvirt] [PATCH v1 00/26] move qemucaps validations from qemu_command to qemu_domain

(series based on master commit 97cafa610ecf5) This work was proposed by Cole in [1]. This is Cole's reasoning for it, copy/pasted from [1]: ------- The benefits of moving to validate time is that XML is rejected by 'virsh define' rather than at 'virsh start' time. It also makes it easier to follow the cli building code, and makes it easier to verify qemu_command.c test suite code coverage for the important stuff like covering every CLI option. It's also a good intermediate step for sharing validation with domain capabilities building, like is done presently for rng models. ------- Cole also mentioned that the machine features validation was a good place to start. I took it a step further and did it across the board on all qemu_command.c. This series didn't create any new validation, just moved them to domain define time. Any other outcome is unintended. Not all cases where covered in this work. For a first version I decided to do only the most trivial cases. These are the other cases I left out for another day: - all verifications contained in functions that are also called by qemu_hotplug.c. This means that the hotplug process will also use the validation code, and we can't just move it to qemu_domain.c. Besides, not all validation done in domain define time applies to hotplug, so it's not simply a matter of calling the same function from qemu_domain in qemu_hotplug. I have patches that moved the verification of all virtio options to qemu_domain.c, while also considering qemu_hotplug validation. In the end I decided to leave it away from this work for now because (1) it took 8 patches just for virtio case alone and (2) there are a lot of these cases in qemu_command.c and it would be too much to do it all at in this same series. - moving CPU Model validation is trickier than the rest because there are code in DefPostParse() that makes CPU Model changes that are then validated in qemu_command.c. Moving the validation to define time doesn't cut in this case - the validation is considering PostParse changes in the CPU Model and some of the will fail if done by qemuDomainDefValidate time. I didn't think too much about how to handle this case, but given that the approach would be different from the other cases handled here, I left it out too. - SHMem: part of SHMem validation is being used by hotplug code. I could've moved the non-hotplug validation to define time, instead I decided it's better to to leave it to do it all at once in the future. - DBus-VMState: validation of this fella must be done by first querying if the hash vm->priv->dbusVMState has elements. qemuDomainDefValidate does not have 'vm->priv' in it's API, meaning that I would need to either change the API to include it (which means changing domainValidateCallback), or do the validation by another branch where I can get access to vm->priv. - vmcoreinfo: there are no challenges in moving vmcoreinfo validation to qemuDomainDefValidate. The problem were the unit tests. Moving this validation to domain define time breaks 925 tests on qemuxml2xmltest.c, including tests labelled as 'minimal' which should pass under any circurstances, as far as I understand. It is possible to just shoehorn QEMU_CAPS_DEVICE_VMCOREINFO in the qemuCaps of all tests, but this would tamper the idea of having to deal with NONE or LATEST or a specific set of capabilities for certain tests. Another case I would rather discuss separately. [1] https://www.redhat.com/archives/libvir-list/2019-October/msg00568.html Daniel Henrique Barboza (26): qemu_command.c: move PSeries features validation to qemu_domain.c qemu_command.c: move mem.nosharepages validation to qemu_domain.c qemu_command.c: move validation of vmport to qemu_domain.c qemu_command.c: move nvdimm validation to qemu_domain.c qemu_command.c: move I/O APIC validation to qemu_domain.c numa_conf: add virDomainNumaNodesDistancesAreBeingSet() helper qemu_command.c move NUMA validation to qemu_domain.c qemu_command.c: move NVRAM validation to qemu_domain.c qemu_command: move qemuBuildSoundDevStr caps validation to qemu_domain qemu_command.c: move sound codec validation to qemu_domain.c qemu_command: move qemuBuildHubDevStr caps validation to qemu_domain qemu_command: move qemuBuildChrChardevStr caps validation to qemu_domain qemu: move qemuBuildHostdevCommandLine caps validation to qemu_domain qemu_command.c: move vmGenID validation to qemu_domain.c qemu: move qemuBuildSgaCommandLine validation to qemu_domain.c qemu: move virDomainClockDef validation to qemu_domain.c qemu: move qemuBuildPMCommandLine validation to qemu_domain.c qemu: move qemuBuildBootCommandLine validation to qemu_domain.c qemu_command.c: move pcihole64 validation to qemu_domain.c qemu: move qemuBuildGraphicsSDLCommandLine validation to qemu_domain.c qemu: move qemuBuildGraphicsVNCCommandLine validation to qemu_domain.c qemu: move qemuBuildGraphicsSPICECommandLine validation to qemu_domain.c qemu: move qemuBuildGraphicsEGLHeadlessCommandLine validation to qemu_domain.c qemu: move qemuBuildSmartcardCommandLine validation to qemu_domain.c qemu: move qemuBuildConsoleCommandLine validation to qemu_domain.c qemu: move qemuBuildTPMDevStr TPM validation to qemu_domain.c