On Fri, Sep 21, 2012 at 05:28:27PM -0400, Don Slutz wrote: > > On 09/21/12 16:49, Eduardo Habkost wrote: > >On Fri, Sep 21, 2012 at 04:26:58PM -0400, Don Slutz wrote: > >>On 09/21/12 10:18, Eduardo Habkost wrote: > >>>On Thu, Sep 20, 2012 at 04:06:27PM -0400, Don Slutz wrote: > >>>> From http://lkml.indiana.edu/hypermail/linux/kernel/1205.0/00100.html > >>>>EAX should be KVM_CPUID_FEATURES (0x40000001) not 0. > >>>> > >>>>Added hypervisor-vendor=kvm0 to get the older CPUID result. kvm1 selects the newer one. > >>>Why not just make "hypervisor-vendor=kvm" control only the hypervisor > >>>vendor string, and support something like "kvm-hypervisor-level=0" to > >>>restore the old cpuid_hv_level=0 behavior? > >> -cpu host,hypervisor-vendor=kvm,hypervisor-level=0 > >> > >> Does this. > >Good. :-) > > > >>>This is similar to the kvmclock case: it would allow us to make > >>>"hypervisor-vendor=kvm" use saner values as default, but letting old > >>>machine-types to override it for compatibility if required. > >>Right now since I am using env->cpuid_hv_level == 0 as a flag. This > >>means that: > >> > >> -cpu host,hypervisor-level=0,hypervisor-vendor=kvm > >> > >> -cpu host,hypervisor-vendor=kvm,hypervisor-level=0 > >> > >>end up with different CPUID data (Which I do not like). I will fix this in the next round. > >Right. This has to be fixed. > > > >>Did you want me to drop kvm0 and kvm1? > >Yes, if level is already configurable using the hypervisor-level > >property, I don't see the need for kvm0 and kvm1. > > > >If you make kvm_arch_init_vcpu() actually use those fields, you will end > >up implementing what's required to allow migration compatibility to be > >kept (the only thing missing is to make the CPU class a child of > >DeviceState, and add hypervisor-level=0 to the existing machine-types). > >:-) > > > You mean like > http://lists.gnu.org/archive/html/qemu-devel/2012-09/msg03402.html > and > http://lists.gnu.org/archive/html/qemu-devel/2012-09/msg03405.html > already change kvm_arch_init_vcpu(). Yes! Sorry, I hadn't reviewed all of your previous series yet. :-) > I did not know that I need to > make the CPU class a child of DeviceState. You don't. But we plan to do that, eventually, so we can put CPU compatibility properties into machine-types. > Nor that I needed to add hypervisor-vendor=kvm,hypervisor-level=0 to > the existing machine-types. Since without specifying > hypervisor-level=0 it defaults to 0 and kvm_arch_init_vcpu() will > default to setting hypervisor-vendor=kvm. What I would like to do is: to change the default to 0x40000001 (that's the correct value), but make the pc-1.1 and older machine-types keep the hypervisor-level=0 default for compatibility. (But to be able to do that, we need to first make the CPU class a child of DeviceState, so that's something to be done later) -- Eduardo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
