On Wed, Aug 30, 2023 at 09:45:58AM +0800, Xiaoyao Li <xiaoyao.li@xxxxxxxxx> wrote: > On 8/29/2023 10:40 PM, Philippe Mathieu-Daudé wrote: > > On 18/8/23 11:49, Xiaoyao Li wrote: > > > Introduce kvm_arch_pre_create_vcpu(), to perform arch-dependent > > > work prior to create any vcpu. This is for i386 TDX because it needs > > > call TDX_INIT_VM before creating any vcpu. > > > > > > Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx> > > > Acked-by: Gerd Hoffmann <kraxel@xxxxxxxxxx> > > > --- > > > accel/kvm/kvm-all.c | 12 ++++++++++++ > > > include/sysemu/kvm.h | 1 + > > > 2 files changed, 13 insertions(+) > > > > > > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > > > index c9f3aab5e587..5071af917ae0 100644 > > > --- a/accel/kvm/kvm-all.c > > > +++ b/accel/kvm/kvm-all.c > > > @@ -422,6 +422,11 @@ static int kvm_get_vcpu(KVMState *s, unsigned > > > long vcpu_id) > > > return kvm_vm_ioctl(s, KVM_CREATE_VCPU, (void *)vcpu_id); > > > } > > > +int __attribute__ ((weak)) kvm_arch_pre_create_vcpu(CPUState *cpu) > > > +{ > > > + return 0; > > > +} > > > > kvm_arch_init_vcpu() is implemented for each arch. Why not use the > > same approach here? > > Because only x86 needs it currently, for TDX. Other arches don't require an > implementation. > > If don't provide the _weak_ function, it needs to implement the empty > function (justing return 0) in all the other arches just as the placeholder. > If QEMU community prefers this approach, I can change to it in next version. Alternative is to move the hook to x86 specific function, not common kvm function. With my quick grepping, x86_cpus_init() or x86_cpu_realizefn(). -- Isaku Yamahata <isaku.yamahata@xxxxxxxxxxxxxxx>