From: isaku.yamahata@intel.com
To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com,
Paolo Bonzini <pbonzini@redhat.com>,
erdemaktas@google.com, Sean Christopherson <seanjc@google.com>,
Sagi Shahar <sagis@google.com>
Subject: [RFC PATCH v6 091/104] KVM: TDX: Handle TDX PV HLT hypercall
Date: Thu, 5 May 2022 11:15:25 -0700 [thread overview]
Message-ID: <c020ee0b90c424a7010e979c9b32a28e9c488a51.1651774251.git.isaku.yamahata@intel.com> (raw)
In-Reply-To: <cover.1651774250.git.isaku.yamahata@intel.com>
From: Isaku Yamahata <isaku.yamahata@intel.com>
Wire up TDX PV HLT hypercall to the KVM backend function.
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
arch/x86/kvm/vmx/tdx.c | 42 +++++++++++++++++++++++++++++++++++++++++-
arch/x86/kvm/vmx/tdx.h | 3 +++
2 files changed, 44 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index c7cdfee397ec..631917eb873e 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -653,7 +653,32 @@ void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
bool tdx_protected_apic_has_interrupt(struct kvm_vcpu *vcpu)
{
- return pi_has_pending_interrupt(vcpu);
+ bool ret = pi_has_pending_interrupt(vcpu);
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ if (ret || vcpu->arch.mp_state != KVM_MP_STATE_HALTED)
+ return true;
+
+ if (tdx->interrupt_disabled_hlt)
+ return false;
+
+ /*
+ * This is for the case where the virtual interrupt is recognized,
+ * i.e. set in vmcs.RVI, between the STI and "HLT". KVM doesn't have
+ * access to RVI and the interrupt is no longer in the PID (because it
+ * was "recognized". It doesn't get delivered in the guest because the
+ * TDCALL completes before interrupts are enabled.
+ *
+ * TDX modules sets RVI while in an STI interrupt shadow.
+ * - TDExit(typically TDG.VP.VMCALL<HLT>) from the guest to TDX module.
+ * The interrupt shadow at this point is gone.
+ * - It knows that there is an interrupt that can be delivered
+ * (RVI > PPR && EFLAGS.IF=1, the other conditions of 29.2.2 don't
+ * matter)
+ * - It forwards the TDExit nevertheless, to a clueless hypervisor that
+ * has no way to glean either RVI or PPR.
+ */
+ return !!xchg(&tdx->buggy_hlt_workaround, 0);
}
void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
@@ -966,6 +991,17 @@ static int tdx_emulate_cpuid(struct kvm_vcpu *vcpu)
return 1;
}
+static int tdx_emulate_hlt(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_tdx *tdx = to_tdx(vcpu);
+
+ /* See tdx_protected_apic_has_interrupt() to avoid heavy seamcall */
+ tdx->interrupt_disabled_hlt = tdvmcall_a0_read(vcpu);;
+
+ tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_SUCCESS);
+ return kvm_emulate_halt_noskip(vcpu);
+}
+
static int handle_tdvmcall(struct kvm_vcpu *vcpu)
{
if (tdvmcall_exit_type(vcpu))
@@ -974,6 +1010,8 @@ static int handle_tdvmcall(struct kvm_vcpu *vcpu)
switch (tdvmcall_leaf(vcpu)) {
case EXIT_REASON_CPUID:
return tdx_emulate_cpuid(vcpu);
+ case EXIT_REASON_HLT:
+ return tdx_emulate_hlt(vcpu);
default:
break;
}
@@ -1311,6 +1349,8 @@ void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
struct kvm_vcpu *vcpu = apic->vcpu;
struct vcpu_tdx *tdx = to_tdx(vcpu);
+ /* See comment in tdx_protected_apic_has_interrupt(). */
+ tdx->buggy_hlt_workaround = 1;
/* TDX supports only posted interrupt. No lapic emulation. */
__vmx_deliver_posted_interrupt(vcpu, &tdx->pi_desc, vector);
}
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index b0bb239b51bf..a456ca6ec187 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -116,6 +116,9 @@ struct vcpu_tdx {
bool host_state_need_restore;
u64 msr_host_kernel_gs_base;
+ bool interrupt_disabled_hlt;
+ unsigned int buggy_hlt_workaround;
+
/*
* Dummy to make pmu_intel not corrupt memory.
* TODO: Support PMU for TDX. Future work.
--
2.25.1
next prev parent reply other threads:[~2022-05-05 18:28 UTC|newest]
Thread overview: 146+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-05 18:13 [RFC PATCH v6 000/104] KVM TDX basic feature support isaku.yamahata
2022-05-05 18:13 ` [RFC PATCH v6 001/104] KVM: x86: Move check_processor_compatibility from init ops to runtime ops isaku.yamahata
2022-05-05 18:13 ` [RFC PATCH v6 002/104] Partially revert "KVM: Pass kvm_init()'s opaque param to additional arch funcs" isaku.yamahata
2022-05-05 18:13 ` [RFC PATCH v6 003/104] KVM: Refactor CPU compatibility check on module initialiization isaku.yamahata
2022-05-23 22:27 ` Sagi Shahar
2022-05-26 19:03 ` Isaku Yamahata
2022-05-05 18:13 ` [RFC PATCH v6 004/104] KVM: VMX: Move out vmx_x86_ops to 'main.c' to wrap VMX and TDX isaku.yamahata
2022-05-05 18:13 ` [RFC PATCH v6 005/104] x86/virt/vmx/tdx: export platform_has_tdx isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 006/104] KVM: TDX: Detect CPU feature on kernel module initialization isaku.yamahata
2022-05-23 23:47 ` Sagi Shahar
2022-05-26 19:28 ` Isaku Yamahata
2022-06-01 22:11 ` Kai Huang
2022-05-05 18:14 ` [RFC PATCH v6 007/104] KVM: Enable hardware before doing arch VM initialization isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 008/104] KVM: x86: Refactor KVM VMX module init/exit functions isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 009/104] KVM: TDX: Add placeholders for TDX VM/vcpu structure isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 010/104] x86/virt/tdx: Add a helper function to return system wide info about TDX module isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 011/104] KVM: TDX: Initialize TDX module when loading kvm_intel.ko isaku.yamahata
2022-05-06 13:57 ` Xiaoyao Li
2022-05-06 21:29 ` Isaku Yamahata
2022-05-05 18:14 ` [RFC PATCH v6 012/104] KVM: x86: Introduce vm_type to differentiate default VMs from confidential VMs isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 013/104] KVM: TDX: Make TDX VM type supported isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 014/104] [MARKER] The start of TDX KVM patch series: TDX architectural definitions isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 015/104] KVM: TDX: Define " isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 016/104] KVM: TDX: Add TDX "architectural" error codes isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 017/104] KVM: TDX: Add C wrapper functions for SEAMCALLs to the TDX module isaku.yamahata
2022-05-06 8:56 ` Xiaoyao Li
2022-05-06 21:35 ` Isaku Yamahata
2022-05-05 18:14 ` [RFC PATCH v6 018/104] KVM: TDX: Add helper functions to print TDX SEAMCALL error isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 019/104] [MARKER] The start of TDX KVM patch series: TD VM creation/destruction isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 020/104] KVM: TDX: Stub in tdx.h with structs, accessors, and VMCS helpers isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 021/104] x86/cpu: Add helper functions to allocate/free TDX private host key id isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 022/104] KVM: TDX: create/destroy VM structure isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 023/104] KVM: TDX: x86: Add ioctl to get TDX systemwide parameters isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 024/104] KVM: TDX: Add place holder for TDX VM specific mem_enc_op ioctl isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 025/104] KVM: TDX: initialize VM with TDX specific parameters isaku.yamahata
2022-05-06 5:27 ` Xiaoyao Li
2022-05-06 13:54 ` Xiaoyao Li
2022-05-09 15:18 ` Isaku Yamahata
2022-05-13 12:34 ` Kai Huang
2022-05-05 18:14 ` [RFC PATCH v6 026/104] KVM: TDX: Make KVM_CAP_SET_IDENTITY_MAP_ADDR unsupported for TDX isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 027/104] KVM: TDX: Make pmu_intel.c ignore guest TD case isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 028/104] [MARKER] The start of TDX KVM patch series: TD vcpu creation/destruction isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 029/104] KVM: TDX: allocate/free TDX vcpu structure isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 030/104] " isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 031/104] KVM: TDX: Do TDX specific vcpu initialization isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 032/104] [MARKER] The start of TDX KVM patch series: KVM MMU GPA shared bits isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 033/104] KVM: x86/mmu: introduce config for PRIVATE KVM MMU isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 034/104] KVM: x86/mmu: Add address conversion functions for TDX shared bits isaku.yamahata
2022-05-10 0:16 ` Kai Huang
2022-05-12 9:50 ` Isaku Yamahata
2022-05-05 18:14 ` [RFC PATCH v6 035/104] [MARKER] The start of TDX KVM patch series: KVM TDP refactoring for TDX isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 036/104] KVM: x86/mmu: Explicitly check for MMIO spte in fast page fault isaku.yamahata
2022-08-01 22:27 ` David Matlack
2022-08-01 23:27 ` Sean Christopherson
2022-08-02 1:46 ` Huang, Kai
2022-08-02 16:34 ` David Matlack
2022-08-03 0:28 ` Kai Huang
2022-05-05 18:14 ` [RFC PATCH v6 037/104] KVM: x86/mmu: Allow non-zero value for non-present SPTE isaku.yamahata
2022-08-04 22:54 ` David Matlack
2022-08-04 23:18 ` David Matlack
2022-08-05 0:03 ` Huang, Kai
2022-08-05 16:46 ` David Matlack
2022-08-05 17:14 ` Sean Christopherson
2022-08-04 23:23 ` Sean Christopherson
2022-08-04 23:43 ` David Matlack
2022-05-05 18:14 ` [RFC PATCH v6 038/104] KVM: x86/mmu: Track shadow MMIO value/mask on a per-VM basis isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 039/104] KVM: x86/mmu: Disallow fast page fault on private GPA isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 040/104] KVM: x86/mmu: Allow per-VM override of the TDP max page level isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 041/104] KVM: x86/mmu: Zap only leaf SPTEs for deleted/moved memslot for private mmu isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 042/104] KVM: VMX: Introduce test mode related to EPT violation VE isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 043/104] [MARKER] The start of TDX KVM patch series: KVM TDP MMU hooks isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 044/104] KVM: x86/mmu: Focibly use TDP MMU for TDX isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 045/104] KVM: x86/mmu: Add a private pointer to struct kvm_mmu_page isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 046/104] KVM: x86/tdp_mmu: refactor kvm_tdp_mmu_map() isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 047/104] KVM: x86/tdp_mmu: Support TDX private mapping for TDP MMU isaku.yamahata
2022-05-27 17:38 ` Paolo Bonzini
2022-06-01 20:49 ` Isaku Yamahata
2022-05-05 18:14 ` [RFC PATCH v6 048/104] [MARKER] The start of TDX KVM patch series: TDX EPT violation isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 049/104] KVM: x86/mmu: Disallow dirty logging for x86 TDX isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 050/104] KVM: x86/tdp_mmu: Ignore unsupported mmu operation on private GFNs isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 051/104] KVM: VMX: Split out guts of EPT violation to common/exposed function isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 052/104] KVM: VMX: Move setting of EPT MMU masks to common VT-x code isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 053/104] KVM: TDX: Add load_mmu_pgd method for TDX isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 054/104] KVM: TDX: don't request KVM_REQ_APIC_PAGE_RELOAD isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 055/104] KVM: TDX: TDP MMU TDX support isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 056/104] [MARKER] The start of TDX KVM patch series: KVM TDP MMU MapGPA isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 057/104] KVM: x86/mmu: steal software usable git to record if GFN is for shared or not isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 058/104] KVM: x86/tdp_mmu: implement MapGPA hypercall for TDX isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 059/104] KVM: x86/mmu: Introduce kvm_mmu_map_tdp_page() for use by TDX isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 060/104] [MARKER] The start of TDX KVM patch series: TD finalization isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 061/104] KVM: TDX: Create initial guest memory isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 062/104] KVM: TDX: Finalize VM initialization isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 063/104] [MARKER] The start of TDX KVM patch series: TD vcpu enter/exit isaku.yamahata
2022-05-05 18:14 ` [RFC PATCH v6 064/104] KVM: TDX: Add helper assembly function to TDX vcpu isaku.yamahata
2022-05-31 15:58 ` Paolo Bonzini
2022-06-01 20:50 ` Isaku Yamahata
2022-05-05 18:14 ` [RFC PATCH v6 065/104] KVM: TDX: Implement TDX vcpu enter/exit path isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 066/104] KVM: TDX: vcpu_run: save/restore host state(host kernel gs) isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 067/104] KVM: TDX: restore host xsave state when exit from the guest TD isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 068/104] KVM: x86: Allow to update cached values in kvm_user_return_msrs w/o wrmsr isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 069/104] KVM: TDX: restore user ret MSRs isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 070/104] [MARKER] The start of TDX KVM patch series: TD vcpu exits/interrupts/hypercalls isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 071/104] KVM: TDX: complete interrupts after tdexit isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 072/104] KVM: TDX: restore debug store when TD exit isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 073/104] KVM: TDX: handle vcpu migration over logical processor isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 074/104] KVM: x86: Add a switch_db_regs flag to handle TDX's auto-switched behavior isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 075/104] KVM: TDX: Add support for find pending IRQ in a protected local APIC isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 076/104] KVM: x86: Assume timer IRQ was injected if APIC state is proteced isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 077/104] KVM: TDX: remove use of struct vcpu_vmx from posted_interrupt.c isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 078/104] KVM: TDX: Implement interrupt injection isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 079/104] KVM: TDX: Implements vcpu request_immediate_exit isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 080/104] KVM: TDX: Implement methods to inject NMI isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 081/104] KVM: VMX: Modify NMI and INTR handlers to take intr_info as function argument isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 082/104] KVM: VMX: Move NMI/exception handler to common helper isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 083/104] KVM: x86: Split core of hypercall emulation to helper function isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 084/104] KVM: TDX: Add a place holder to handle TDX VM exit isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 085/104] KVM: TDX: handle EXIT_REASON_OTHER_SMI isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 086/104] KVM: TDX: handle ept violation/misconfig exit isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 087/104] KVM: TDX: handle EXCEPTION_NMI and EXTERNAL_INTERRUPT isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 088/104] KVM: TDX: Add a place holder for handler of TDX hypercalls (TDG.VP.VMCALL) isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 089/104] KVM: TDX: handle KVM hypercall with TDG.VP.VMCALL isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 090/104] KVM: TDX: Handle TDX PV CPUID hypercall isaku.yamahata
2022-06-14 18:15 ` Sagi Shahar
2022-06-29 10:13 ` Isaku Yamahata
2022-07-18 22:37 ` Sagi Shahar
2022-07-19 19:23 ` Sean Christopherson
2022-05-05 18:15 ` isaku.yamahata [this message]
2022-05-05 18:15 ` [RFC PATCH v6 092/104] KVM: TDX: Handle TDX PV port io hypercall isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 093/104] KVM: TDX: Handle TDX PV MMIO hypercall isaku.yamahata
2022-06-14 18:08 ` Sagi Shahar
2022-06-29 10:17 ` Isaku Yamahata
2022-05-05 18:15 ` [RFC PATCH v6 094/104] KVM: TDX: Implement callbacks for MSR operations for TDX isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 095/104] KVM: TDX: Handle TDX PV rdmsr/wrmsr hypercall isaku.yamahata
2022-06-10 21:04 ` Sagi Shahar
2022-06-29 10:24 ` Isaku Yamahata
2022-05-05 18:15 ` [RFC PATCH v6 096/104] KVM: TDX: Handle TDX PV report fatal error hypercall isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 097/104] KVM: TDX: Handle TDX PV map_gpa hypercall isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 098/104] KVM: TDX: Handle TDG.VP.VMCALL<GetTdVmCallInfo> hypercall isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 099/104] KVM: TDX: Silently discard SMI request isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 100/104] KVM: TDX: Silently ignore INIT/SIPI isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 101/104] KVM: TDX: Add methods to ignore accesses to CPU state isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 102/104] Documentation/virtual/kvm: Document on Trust Domain Extensions(TDX) isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 103/104] KVM: x86: design documentation on TDX support of x86 KVM TDP MMU isaku.yamahata
2022-05-05 18:15 ` [RFC PATCH v6 104/104] [MARKER] the end of (the first phase of) TDX KVM patch series isaku.yamahata
2022-05-31 14:46 ` [RFC PATCH v6 000/104] KVM TDX basic feature support Paolo Bonzini
2022-06-01 20:53 ` Isaku Yamahata
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