Reuse "-cpu,tsc-frequency=" to get user wanted tsc frequency and pass it to KVM_TDX_INIT_VM. Besides, sanity check the tsc frequency to be in the legal range and legal granularity (required by TDX module). Signed-off-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx> --- target/i386/kvm/kvm.c | 8 ++++++++ target/i386/kvm/tdx.c | 18 ++++++++++++++++++ 2 files changed, 26 insertions(+) diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index f2d71359b59d..4a8b6e2c8797 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -806,6 +806,14 @@ static int kvm_arch_set_tsc_khz(CPUState *cs) int r, cur_freq; bool set_ioctl = false; + /* + * TD guest's TSC is immutable, it cannot be set/changed via + * KVM_SET_TSC_KHZ, but only be initialized via KVM_TDX_INIT_VM + */ + if (is_tdx_vm()) { + return 0; + } + if (!env->tsc_khz) { return 0; } diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c index a76c41fe5724..94a9c1ea7e9c 100644 --- a/target/i386/kvm/tdx.c +++ b/target/i386/kvm/tdx.c @@ -26,6 +26,9 @@ #define TDX_TD_ATTRIBUTES_PKS BIT_ULL(30) #define TDX_TD_ATTRIBUTES_PERFMON BIT_ULL(63) +#define TDX_MIN_TSC_FREQUENCY_KHZ (100 * 1000) +#define TDX_MAX_TSC_FREQUENCY_KHZ (10 * 1000 * 1000) + static TdxGuest *tdx_guest; /* It's valid after kvm_confidential_guest_init()->kvm_tdx_init() */ @@ -209,6 +212,20 @@ int tdx_pre_create_vcpu(CPUState *cpu) goto out; } + r = -EINVAL; + if (env->tsc_khz && (env->tsc_khz < TDX_MIN_TSC_FREQUENCY_KHZ || + env->tsc_khz > TDX_MAX_TSC_FREQUENCY_KHZ)) { + error_report("Invalid TSC %ld KHz, must specify cpu_frequency between [%d, %d] kHz", + env->tsc_khz, TDX_MIN_TSC_FREQUENCY_KHZ, + TDX_MAX_TSC_FREQUENCY_KHZ); + goto out; + } + + if (env->tsc_khz % (25 * 1000)) { + error_report("Invalid TSC %ld KHz, it must be multiple of 25MHz", env->tsc_khz); + goto out; + } + r = setup_td_guest_attributes(x86cpu); if (r) { goto out; @@ -219,6 +236,7 @@ int tdx_pre_create_vcpu(CPUState *cpu) init_vm.cpuid = (__u64)(&cpuid_data); init_vm.max_vcpus = ms->smp.cpus; + init_vm.tsc_khz = env->tsc_khz; init_vm.attributes = tdx_guest->attributes; r = tdx_vm_ioctl(KVM_TDX_INIT_VM, 0, &init_vm); -- 2.27.0