On 7/16/2021 5:52 PM, Paolo Bonzini wrote:
On 16/07/21 08:48, Zeng Guang wrote:
+ if (!(_cpu_based_3rd_exec_control & TERTIARY_EXEC_IPI_VIRT))
+ enable_ipiv = 0;
+
}
Please move this to hardware_setup(), using a new function
cpu_has_vmx_ipiv() in vmx/capabilities.h.
ok, we will change it to follow current framework.
if (_cpu_based_exec_control &
CPU_BASED_ACTIVATE_TERTIARY_CONTROLS) {
- u64 opt3 = 0;
+ u64 opt3 = enable_ipiv ? TERTIARY_EXEC_IPI_VIRT : 0;
u64 min3 = 0;
I like the idea of changing opt3, but it's different from how
setup_vmcs_config works for the other execution controls. Let me
think if it makes sense to clean this up, and move the handling of
other module parameters from hardware_setup() to setup_vmcs_config().
May be an exception for ipiv feature ?
+
+ if (vmx->ipiv_active)
+ install_pid(vmx);
This should be if (enable_ipiv) instead, I think.
In fact, in all other places that are using vmx->ipiv_active, you can
actually replace it with enable_ipiv; they are all reached only with
kvm_vcpu_apicv_active(vcpu) == true.
enable_ipiv as a global variable indicates the hardware capability to
enable IPIv. Each VM may have different IPIv configuration according to
kvm_vcpu_apicv_active status. So we use ipiv_active per VM to enclose
IPIv related operations.
+ if (!enable_apicv) {
+ enable_ipiv = 0;
+ vmcs_config.cpu_based_3rd_exec_ctrl &= ~TERTIARY_EXEC_IPI_VIRT;
+ }
The assignment to vmcs_config.cpu_based_3rd_exec_ctrl should not be
necessary; kvm_vcpu_apicv_active will always be false in that case and
IPI virtualization would never be enabled.
We originally intend to make vmcs_config consistent with the actual ipiv
capability and decouple it from other factors. As you mentioned , it's
not necessary to update vmcs_config.cpu_based_3rd_exec_ctrl in this
case. We will remove it.
Thanks.
Paolo
