On Wed, Jan 12, 2022 at 10:16:33AM +0000, Peter Maydell wrote: > On Wed, 12 Jan 2022 at 10:14, Daniel P. Berrangé <berra...@redhat.com> wrote: > > > > On Wed, Jan 12, 2022 at 11:55:17AM -0500, Yang Zhong wrote: > > > When Libvirt start, it get the vcpu's unavailable-features from > > > /machine/unattached/device[0] path by qom-get command, but in SGX > > > guest, since the sgx-epc virtual device is initialized before VCPU > > > creation(virtual sgx need set the virtual EPC info in the cpuid). This > > > /machine/unattached/device[0] is occupied by sgx-epc device, which > > > fail to get the unvailable-features from /machine/unattached/device[0]. > > > > If libvirt decides to enable SGX in a VM, then surely it knows > > that it should just query /machine/unattached/device[1] to get > > the CPU features instead. Why do we need to do anything in QEMU ? > > libvirt having to know it needs to look at /machine/unattached/device[n] > for anything is a bit fragile, really... it's effectively encoding > knowledge about what order things happen to get created inside QEMU.
So how do CPUs and other devices end up being under /unattached/ ? Can we ensure that *all* QEMU devices have a well defined attachment point ? Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
