Re: [PATCH v8 08/55] i386/tdx: Initialize TDX before creating TD vcpus

[Zhao Liu <zhao1.liu@intel.com>]

On Tue, Apr 01, 2025 at 09:01:18AM -0400, Xiaoyao Li wrote:
> Date: Tue,  1 Apr 2025 09:01:18 -0400
> From: Xiaoyao Li <xiaoyao.li@intel.com>
> Subject: [PATCH v8 08/55] i386/tdx: Initialize TDX before creating TD vcpus
> X-Mailer: git-send-email 2.34.1
> 
> Invoke KVM_TDX_INIT_VM in kvm_arch_pre_create_vcpu() that
> KVM_TDX_INIT_VM configures global TD configurations, e.g. the canonical
> CPUID config, and must be executed prior to creating vCPUs.
> 
> Use kvm_x86_arch_cpuid() to setup the CPUID settings for TDX VM.
> 
> Note, this doesn't address the fact that QEMU may change the CPUID
> configuration when creating vCPUs, i.e. punts on refactoring QEMU to
> provide a stable CPUID config prior to kvm_arch_init().
> 
> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
> Acked-by: Gerd Hoffmann <kraxel@redhat.com>
> Acked-by: Markus Armbruster <armbru@redhat.com>
> ---
> Changes in v8:
> - Drop the code that initializes cpu->kvm_state before
>   kvm_arch_pre_create_vcpu() because it's not needed anymore.
> 
> Changes in v7:
> - Add comments to explain why KVM_TDX_INIT_VM should retry on -EAGAIN;
> - Add retry limit of 10000 times for -EAGAIN on KVM_TDX_INIT_VM;
> 
> Changes in v6:
> - setup xfam explicitly to fit with new uapi;
> - use tdx_caps->cpuid to filter the input of cpuids because now KVM only
>   allows the leafs that reported via KVM_TDX_GET_CAPABILITIES;
> 
> Changes in v4:
> - mark init_vm with g_autofree() and use QEMU_LOCK_GUARD() to eliminate
>   the goto labels; (Daniel)
> Changes in v3:
> - Pass @errp in tdx_pre_create_vcpu() and pass error info to it. (Daniel)
> ---
>  target/i386/kvm/kvm.c       |  16 +++---
>  target/i386/kvm/kvm_i386.h  |   5 ++
>  target/i386/kvm/meson.build |   2 +-
>  target/i386/kvm/tdx-stub.c  |  10 ++++
>  target/i386/kvm/tdx.c       | 105 ++++++++++++++++++++++++++++++++++++
>  target/i386/kvm/tdx.h       |   6 +++
>  6 files changed, 137 insertions(+), 7 deletions(-)
>  create mode 100644 target/i386/kvm/tdx-stub.c

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>