On Thu, Oct 03, 2024, Paolo Bonzini wrote:
> kvm.ko is nothing but library code shared by kvm-intel.ko and kvm-amd.ko.
> It provides no functionality on its own and it is unnecessary unless one
> of the vendor-specific module is compiled. In particular, /dev/kvm is
> not created until one of kvm-intel.ko or kvm-amd.ko is loaded.
>
> Use CONFIG_KVM to decide if it is built-in or a module, but use the
> vendor-specific modules for the actual decision on whether to build it.
>
> This also fixes a build failure when CONFIG_KVM_INTEL and CONFIG_KVM_AMD
> are both disabled. The cpu_emergency_register_virt_callback() function
> is called from kvm.ko, but it is only defined if at least one of
> CONFIG_KVM_INTEL and CONFIG_KVM_AMD is provided.
>
> Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> arch/x86/kvm/Kconfig | 7 +++++--
> arch/x86/kvm/Makefile | 2 +-
> 2 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
> index 730c2f34d347..81bce9dd9331 100644
> --- a/arch/x86/kvm/Kconfig
> +++ b/arch/x86/kvm/Kconfig
> @@ -17,8 +17,8 @@ menuconfig VIRTUALIZATION
>
> if VIRTUALIZATION
>
> -config KVM
> - tristate "Kernel-based Virtual Machine (KVM) support"
> +config KVM_X86_COMMON
Maybe just KVM_X86? I doubt anyone in KVM will care too much, and for the rest
of the kernel, CONFIG_KVM_X86 is likely more intuitive than CONFIG_KVM_X86_COMMON.
