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| author |   Adrian Hunter <adrian.hunter@intel.com> | 2025-01-29 11:59:00 +0200 |
|---|---|---|
| committer |   Paolo Bonzini <pbonzini@redhat.com> | 2025-03-14 14:20:54 -0400 |
| commit | 8af099037527c54399d44c4fd30eab15931700ce (patch) | |
| tree | cc59ea9d5c5bd9c8964e7ac8c5a6f9d2fad532f9 | |
| parent | KVM: TDX: Disable support for TSX and WAITPKG (diff) | |
| download | linux-rng-8af099037527c54399d44c4fd30eab15931700ce.tar.xz linux-rng-8af099037527c54399d44c4fd30eab15931700ce.zip | |
KVM: TDX: Save and restore IA32_DEBUGCTL
Save the IA32_DEBUGCTL MSR before entering a TDX VCPU and restore it
afterwards. The TDX Module preserves bits 1, 12, and 14, so if no
other bits are set, no restore is done.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Message-ID: <20250129095902.16391-12-adrian.hunter@intel.com>
Reviewed-by: Xiayao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/vmx/tdx.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index 06decfe9eb5e..7ad680b5f771 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -688,6 +688,8 @@ void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) else vt->msr_host_kernel_gs_base = read_msr(MSR_KERNEL_GS_BASE); + vt->host_debugctlmsr = get_debugctlmsr(); + vt->guest_state_loaded = true; } @@ -831,11 +833,15 @@ static void tdx_load_host_xsave_state(struct kvm_vcpu *vcpu) if (kvm_host.xss != (kvm_tdx->xfam & kvm_caps.supported_xss)) wrmsrl(MSR_IA32_XSS, kvm_host.xss); } -EXPORT_SYMBOL_GPL(kvm_load_host_xsave_state); + +#define TDX_DEBUGCTL_PRESERVED (DEBUGCTLMSR_BTF | \ + DEBUGCTLMSR_FREEZE_PERFMON_ON_PMI | \ + DEBUGCTLMSR_FREEZE_IN_SMM) fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, bool force_immediate_exit) { struct vcpu_tdx *tdx = to_tdx(vcpu); + struct vcpu_vt *vt = to_vt(vcpu); /* * force_immediate_exit requires vCPU entering for events injection with @@ -851,6 +857,9 @@ fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, bool force_immediate_exit) tdx_vcpu_enter_exit(vcpu); + if (vt->host_debugctlmsr & ~TDX_DEBUGCTL_PRESERVED) + update_debugctlmsr(vt->host_debugctlmsr); + tdx_load_host_xsave_state(vcpu); tdx->guest_entered = true; |