From: David Woodhouse <dwmw@xxxxxxxxxxxx> This allows the host to indicate that MSI emulation supports 15-bit destination IDs, allowing up to 32768 CPUs without interrupt remapping. cf. https://patchwork.kernel.org/patch/11816693/ for qemu Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> --- arch/x86/kernel/kvm.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 1c0f2560a41c..b82de2843814 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -740,6 +740,11 @@ static void __init kvm_apic_init(void) #endif } +static bool __init kvm_msi_ext_dest_id(void) +{ + return kvm_para_has_feature(KVM_FEATURE_MSI_EXT_DEST_ID); +} + static void __init kvm_init_platform(void) { kvmclock_init(); @@ -769,6 +774,7 @@ const __initconst struct hypervisor_x86 x86_hyper_kvm = { .type = X86_HYPER_KVM, .init.guest_late_init = kvm_guest_init, .init.x2apic_available = kvm_para_available, + .init.msi_ext_dest_id = kvm_msi_ext_dest_id, .init.init_platform = kvm_init_platform, #if defined(CONFIG_AMD_MEM_ENCRYPT) .runtime.sev_es_hcall_prepare = kvm_sev_es_hcall_prepare, -- 2.26.2
