linux/arch/x86/kvm/vmx/x86_ops.h

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KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __KVM_X86_VMX_X86_OPS_H
#define __KVM_X86_VMX_X86_OPS_H
#include <linux/kvm_host.h>
#include "x86.h"
__init int vmx_hardware_setup(void);
extern struct kvm_x86_ops vt_x86_ops __initdata;
extern struct kvm_x86_init_ops vt_init_ops __initdata;
void vmx_hardware_unsetup(void);
int vmx_check_processor_compat(void);
int vmx_enable_virtualization_cpu(void);
void vmx_disable_virtualization_cpu(void);
void vmx_emergency_disable_virtualization_cpu(void);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
int vmx_vm_init(struct kvm *kvm);
void vmx_vm_destroy(struct kvm *kvm);
int vmx_vcpu_precreate(struct kvm *kvm);
int vmx_vcpu_create(struct kvm_vcpu *vcpu);
int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu);
fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
void vmx_vcpu_free(struct kvm_vcpu *vcpu);
void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
void vmx_vcpu_put(struct kvm_vcpu *vcpu);
int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath);
void vmx_handle_exit_irqoff(struct kvm_vcpu *vcpu);
int vmx_skip_emulated_instruction(struct kvm_vcpu *vcpu);
void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu);
int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
#ifdef CONFIG_KVM_SMM
int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection);
int vmx_enter_smm(struct kvm_vcpu *vcpu, union kvm_smram *smram);
int vmx_leave_smm(struct kvm_vcpu *vcpu, const union kvm_smram *smram);
void vmx_enable_smi_window(struct kvm_vcpu *vcpu);
#endif
int vmx_check_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
void *insn, int insn_len);
int vmx_check_intercept(struct kvm_vcpu *vcpu,
struct x86_instruction_info *info,
enum x86_intercept_stage stage,
struct x86_exception *exception);
bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu);
void vmx_migrate_timers(struct kvm_vcpu *vcpu);
void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu);
void vmx_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu);
void vmx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
int trig_mode, int vector);
void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu);
bool vmx_has_emulated_msr(struct kvm *kvm, u32 index);
void vmx_recalc_msr_intercepts(struct kvm_vcpu *vcpu);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
void vmx_update_exception_bitmap(struct kvm_vcpu *vcpu);
int vmx_get_feature_msr(u32 msr, u64 *data);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
#define vmx_complete_emulated_msr kvm_complete_insn_gp
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg);
void vmx_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
void vmx_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
int vmx_get_cpl(struct kvm_vcpu *vcpu);
void vmx_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l);
bool vmx_is_valid_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level);
void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
bool vmx_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4);
int vmx_set_efer(struct kvm_vcpu *vcpu, u64 efer);
void vmx_get_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
void vmx_set_idt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
void vmx_get_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
void vmx_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
KVM: x86: Load DR6 with guest value only before entering .vcpu_run() loop Move the conditional loading of hardware DR6 with the guest's DR6 value out of the core .vcpu_run() loop to fix a bug where KVM can load hardware with a stale vcpu->arch.dr6. When the guest accesses a DR and host userspace isn't debugging the guest, KVM disables DR interception and loads the guest's values into hardware on VM-Enter and saves them on VM-Exit. This allows the guest to access DRs at will, e.g. so that a sequence of DR accesses to configure a breakpoint only generates one VM-Exit. For DR0-DR3, the logic/behavior is identical between VMX and SVM, and also identical between KVM_DEBUGREG_BP_ENABLED (userspace debugging the guest) and KVM_DEBUGREG_WONT_EXIT (guest using DRs), and so KVM handles loading DR0-DR3 in common code, _outside_ of the core kvm_x86_ops.vcpu_run() loop. But for DR6, the guest's value doesn't need to be loaded into hardware for KVM_DEBUGREG_BP_ENABLED, and SVM provides a dedicated VMCB field whereas VMX requires software to manually load the guest value, and so loading the guest's value into DR6 is handled by {svm,vmx}_vcpu_run(), i.e. is done _inside_ the core run loop. Unfortunately, saving the guest values on VM-Exit is initiated by common x86, again outside of the core run loop. If the guest modifies DR6 (in hardware, when DR interception is disabled), and then the next VM-Exit is a fastpath VM-Exit, KVM will reload hardware DR6 with vcpu->arch.dr6 and clobber the guest's actual value. The bug shows up primarily with nested VMX because KVM handles the VMX preemption timer in the fastpath, and the window between hardware DR6 being modified (in guest context) and DR6 being read by guest software is orders of magnitude larger in a nested setup. E.g. in non-nested, the VMX preemption timer would need to fire precisely between #DB injection and the #DB handler's read of DR6, whereas with a KVM-on-KVM setup, the window where hardware DR6 is "dirty" extends all the way from L1 writing DR6 to VMRESUME (in L1). L1's view: ========== <L1 disables DR interception> CPU 0/KVM-7289 [023] d.... 2925.640961: kvm_entry: vcpu 0 A: L1 Writes DR6 CPU 0/KVM-7289 [023] d.... 2925.640963: <hack>: Set DRs, DR6 = 0xffff0ff1 B: CPU 0/KVM-7289 [023] d.... 2925.640967: kvm_exit: vcpu 0 reason EXTERNAL_INTERRUPT intr_info 0x800000ec D: L1 reads DR6, arch.dr6 = 0 CPU 0/KVM-7289 [023] d.... 2925.640969: <hack>: Sync DRs, DR6 = 0xffff0ff0 CPU 0/KVM-7289 [023] d.... 2925.640976: kvm_entry: vcpu 0 L2 reads DR6, L1 disables DR interception CPU 0/KVM-7289 [023] d.... 2925.640980: kvm_exit: vcpu 0 reason DR_ACCESS info1 0x0000000000000216 CPU 0/KVM-7289 [023] d.... 2925.640983: kvm_entry: vcpu 0 CPU 0/KVM-7289 [023] d.... 2925.640983: <hack>: Set DRs, DR6 = 0xffff0ff0 L2 detects failure CPU 0/KVM-7289 [023] d.... 2925.640987: kvm_exit: vcpu 0 reason HLT L1 reads DR6 (confirms failure) CPU 0/KVM-7289 [023] d.... 2925.640990: <hack>: Sync DRs, DR6 = 0xffff0ff0 L0's view: ========== L2 reads DR6, arch.dr6 = 0 CPU 23/KVM-5046 [001] d.... 3410.005610: kvm_exit: vcpu 23 reason DR_ACCESS info1 0x0000000000000216 CPU 23/KVM-5046 [001] ..... 3410.005610: kvm_nested_vmexit: vcpu 23 reason DR_ACCESS info1 0x0000000000000216 L2 => L1 nested VM-Exit CPU 23/KVM-5046 [001] ..... 3410.005610: kvm_nested_vmexit_inject: reason: DR_ACCESS ext_inf1: 0x0000000000000216 CPU 23/KVM-5046 [001] d.... 3410.005610: kvm_entry: vcpu 23 CPU 23/KVM-5046 [001] d.... 3410.005611: kvm_exit: vcpu 23 reason VMREAD CPU 23/KVM-5046 [001] d.... 3410.005611: kvm_entry: vcpu 23 CPU 23/KVM-5046 [001] d.... 3410.005612: kvm_exit: vcpu 23 reason VMREAD CPU 23/KVM-5046 [001] d.... 3410.005612: kvm_entry: vcpu 23 L1 writes DR7, L0 disables DR interception CPU 23/KVM-5046 [001] d.... 3410.005612: kvm_exit: vcpu 23 reason DR_ACCESS info1 0x0000000000000007 CPU 23/KVM-5046 [001] d.... 3410.005613: kvm_entry: vcpu 23 L0 writes DR6 = 0 (arch.dr6) CPU 23/KVM-5046 [001] d.... 3410.005613: <hack>: Set DRs, DR6 = 0xffff0ff0 A: <L1 writes DR6 = 1, no interception, arch.dr6 is still '0'> B: CPU 23/KVM-5046 [001] d.... 3410.005614: kvm_exit: vcpu 23 reason PREEMPTION_TIMER CPU 23/KVM-5046 [001] d.... 3410.005614: kvm_entry: vcpu 23 C: L0 writes DR6 = 0 (arch.dr6) CPU 23/KVM-5046 [001] d.... 3410.005614: <hack>: Set DRs, DR6 = 0xffff0ff0 L1 => L2 nested VM-Enter CPU 23/KVM-5046 [001] d.... 3410.005616: kvm_exit: vcpu 23 reason VMRESUME L0 reads DR6, arch.dr6 = 0 Reported-by: John Stultz <jstultz@google.com> Closes: https://lkml.kernel.org/r/CANDhNCq5_F3HfFYABqFGCA1bPd_%2BxgNj-iDQhH4tDk%2Bwi8iZZg%40mail.gmail.com Fixes: 375e28ffc0cf ("KVM: X86: Set host DR6 only on VMX and for KVM_DEBUGREG_WONT_EXIT") Fixes: d67668e9dd76 ("KVM: x86, SVM: isolate vcpu->arch.dr6 from vmcb->save.dr6") Cc: stable@vger.kernel.org Cc: Jim Mattson <jmattson@google.com> Tested-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/r/20250125011833.3644371-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-01-24 17:18:33 -08:00
void vmx_set_dr6(struct kvm_vcpu *vcpu, unsigned long val);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
void vmx_set_dr7(struct kvm_vcpu *vcpu, unsigned long val);
void vmx_sync_dirty_debug_regs(struct kvm_vcpu *vcpu);
void vmx_cache_reg(struct kvm_vcpu *vcpu, enum kvm_reg reg);
unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu);
void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags);
bool vmx_get_if_flag(struct kvm_vcpu *vcpu);
void vmx_flush_tlb_all(struct kvm_vcpu *vcpu);
void vmx_flush_tlb_current(struct kvm_vcpu *vcpu);
void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr);
void vmx_flush_tlb_guest(struct kvm_vcpu *vcpu);
void vmx_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask);
u32 vmx_get_interrupt_shadow(struct kvm_vcpu *vcpu);
void vmx_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall);
void vmx_inject_irq(struct kvm_vcpu *vcpu, bool reinjected);
void vmx_inject_nmi(struct kvm_vcpu *vcpu);
void vmx_inject_exception(struct kvm_vcpu *vcpu);
void vmx_cancel_injection(struct kvm_vcpu *vcpu);
int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection);
int vmx_nmi_allowed(struct kvm_vcpu *vcpu, bool for_injection);
bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu);
void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked);
void vmx_enable_nmi_window(struct kvm_vcpu *vcpu);
void vmx_enable_irq_window(struct kvm_vcpu *vcpu);
void vmx_update_cr8_intercept(struct kvm_vcpu *vcpu, int tpr, int irr);
void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu);
void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu);
void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr);
int vmx_set_identity_map_addr(struct kvm *kvm, u64 ident_addr);
u8 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
void vmx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code);
void vmx_get_entry_info(struct kvm_vcpu *vcpu, u32 *intr_info, u32 *error_code);
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
u64 vmx_get_l2_tsc_offset(struct kvm_vcpu *vcpu);
u64 vmx_get_l2_tsc_multiplier(struct kvm_vcpu *vcpu);
void vmx_write_tsc_offset(struct kvm_vcpu *vcpu);
void vmx_write_tsc_multiplier(struct kvm_vcpu *vcpu);
void vmx_update_cpu_dirty_logging(struct kvm_vcpu *vcpu);
#ifdef CONFIG_X86_64
int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
bool *expired);
void vmx_cancel_hv_timer(struct kvm_vcpu *vcpu);
#endif
void vmx_setup_mce(struct kvm_vcpu *vcpu);
#ifdef CONFIG_KVM_INTEL_TDX
KVM: TDX: Handle vCPU dissociation Handle vCPUs dissociations by invoking SEAMCALL TDH.VP.FLUSH which flushes the address translation caches and cached TD VMCS of a TD vCPU in its associated pCPU. In TDX, a vCPUs can only be associated with one pCPU at a time, which is done by invoking SEAMCALL TDH.VP.ENTER. For a successful association, the vCPU must be dissociated from its previous associated pCPU. To facilitate vCPU dissociation, introduce a per-pCPU list associated_tdvcpus. Add a vCPU into this list when it's loaded into a new pCPU (i.e. when a vCPU is loaded for the first time or migrated to a new pCPU). vCPU dissociations can happen under below conditions: - On the op hardware_disable is called. This op is called when virtualization is disabled on a given pCPU, e.g. when hot-unplug a pCPU or machine shutdown/suspend. In this case, dissociate all vCPUs from the pCPU by iterating its per-pCPU list associated_tdvcpus. - On vCPU migration to a new pCPU. Before adding a vCPU into associated_tdvcpus list of the new pCPU, dissociation from its old pCPU is required, which is performed by issuing an IPI and executing SEAMCALL TDH.VP.FLUSH on the old pCPU. On a successful dissociation, the vCPU will be removed from the associated_tdvcpus list of its previously associated pCPU. - On tdx_mmu_release_hkid() is called. TDX mandates that all vCPUs must be disassociated prior to the release of an hkid. Therefore, dissociation of all vCPUs is a must before executing the SEAMCALL TDH.MNG.VPFLUSHDONE and subsequently freeing the hkid. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Co-developed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Message-ID: <20241112073858.22312-1-yan.y.zhao@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-11-12 15:38:58 +08:00
void tdx_disable_virtualization_cpu(void);
KVM: TDX: create/destroy VM structure Implement managing the TDX private KeyID to implement, create, destroy and free for a TDX guest. When creating at TDX guest, assign a TDX private KeyID for the TDX guest for memory encryption, and allocate pages for the guest. These are used for the Trust Domain Root (TDR) and Trust Domain Control Structure (TDCS). On destruction, free the allocated pages, and the KeyID. Before tearing down the private page tables, TDX requires the guest TD to be destroyed by reclaiming the KeyID. Do it in the vm_pre_destroy() kvm_x86_ops hook. The TDR control structures can be freed in the vm_destroy() hook, which runs last. Co-developed-by: Tony Lindgren <tony.lindgren@linux.intel.com> Signed-off-by: Tony Lindgren <tony.lindgren@linux.intel.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Co-developed-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Kai Huang <kai.huang@intel.com> Co-developed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> --- - Fix build issue in kvm-coco-queue - Init ret earlier to fix __tdx_td_init() error handling. (Chao) - Standardize -EAGAIN for __tdx_td_init() retry errors (Rick) Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-25 12:45:13 -05:00
int tdx_vm_init(struct kvm *kvm);
void tdx_mmu_release_hkid(struct kvm *kvm);
void tdx_vm_destroy(struct kvm *kvm);
int tdx_vm_ioctl(struct kvm *kvm, void __user *argp);
int tdx_vcpu_create(struct kvm_vcpu *vcpu);
void tdx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event);
void tdx_vcpu_free(struct kvm_vcpu *vcpu);
KVM: TDX: Handle vCPU dissociation Handle vCPUs dissociations by invoking SEAMCALL TDH.VP.FLUSH which flushes the address translation caches and cached TD VMCS of a TD vCPU in its associated pCPU. In TDX, a vCPUs can only be associated with one pCPU at a time, which is done by invoking SEAMCALL TDH.VP.ENTER. For a successful association, the vCPU must be dissociated from its previous associated pCPU. To facilitate vCPU dissociation, introduce a per-pCPU list associated_tdvcpus. Add a vCPU into this list when it's loaded into a new pCPU (i.e. when a vCPU is loaded for the first time or migrated to a new pCPU). vCPU dissociations can happen under below conditions: - On the op hardware_disable is called. This op is called when virtualization is disabled on a given pCPU, e.g. when hot-unplug a pCPU or machine shutdown/suspend. In this case, dissociate all vCPUs from the pCPU by iterating its per-pCPU list associated_tdvcpus. - On vCPU migration to a new pCPU. Before adding a vCPU into associated_tdvcpus list of the new pCPU, dissociation from its old pCPU is required, which is performed by issuing an IPI and executing SEAMCALL TDH.VP.FLUSH on the old pCPU. On a successful dissociation, the vCPU will be removed from the associated_tdvcpus list of its previously associated pCPU. - On tdx_mmu_release_hkid() is called. TDX mandates that all vCPUs must be disassociated prior to the release of an hkid. Therefore, dissociation of all vCPUs is a must before executing the SEAMCALL TDH.MNG.VPFLUSHDONE and subsequently freeing the hkid. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Co-developed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Message-ID: <20241112073858.22312-1-yan.y.zhao@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-11-12 15:38:58 +08:00
void tdx_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
int tdx_vcpu_pre_run(struct kvm_vcpu *vcpu);
fastpath_t tdx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags);
void tdx_prepare_switch_to_guest(struct kvm_vcpu *vcpu);
void tdx_vcpu_put(struct kvm_vcpu *vcpu);
KVM: TDX: Add a place holder to handle TDX VM exit Introduce the wiring for handling TDX VM exits by implementing the callbacks .get_exit_info(), .get_entry_info(), and .handle_exit(). Additionally, add error handling during the TDX VM exit flow, and add a place holder to handle various exit reasons. Store VMX exit reason and exit qualification in struct vcpu_vt for TDX, so that TDX/VMX can use the same helpers to get exit reason and exit qualification. Store extended exit qualification and exit GPA info in struct vcpu_tdx because they are used by TDX code only. Contention Handling: The TDH.VP.ENTER operation may contend with TDH.MEM.* operations due to secure EPT or TD EPOCH. If the contention occurs, the return value will have TDX_OPERAND_BUSY set, prompting the vCPU to attempt re-entry into the guest with EXIT_FASTPATH_EXIT_HANDLED, not EXIT_FASTPATH_REENTER_GUEST, so that the interrupts pending during IN_GUEST_MODE can be delivered for sure. Otherwise, the requester of KVM_REQ_OUTSIDE_GUEST_MODE may be blocked endlessly. Error Handling: - TDX_SW_ERROR: This includes #UD caused by SEAMCALL instruction if the CPU isn't in VMX operation, #GP caused by SEAMCALL instruction when TDX isn't enabled by the BIOS, and TDX_SEAMCALL_VMFAILINVALID when SEAM firmware is not loaded or disabled. - TDX_ERROR: This indicates some check failed in the TDX module, preventing the vCPU from running. - Failed VM Entry: Exit to userspace with KVM_EXIT_FAIL_ENTRY. Handle it separately before handling TDX_NON_RECOVERABLE because when off-TD debug is not enabled, TDX_NON_RECOVERABLE is set. - TDX_NON_RECOVERABLE: Set by the TDX module when the error is non-recoverable, indicating that the TDX guest is dead or the vCPU is disabled. A special case is triple fault, which also sets TDX_NON_RECOVERABLE but exits to userspace with KVM_EXIT_SHUTDOWN, aligning with the VMX case. - Any unhandled VM exit reason will also return to userspace with KVM_EXIT_INTERNAL_ERROR. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Chao Gao <chao.gao@intel.com> Message-ID: <20250222014225.897298-4-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-06 13:27:04 -05:00
int tdx_handle_exit(struct kvm_vcpu *vcpu,
enum exit_fastpath_completion fastpath);
void tdx_deliver_interrupt(struct kvm_lapic *apic, int delivery_mode,
int trig_mode, int vector);
KVM: TDX: Implement methods to inject NMI Inject NMI to TDX guest by setting the PEND_NMI TDVPS field to 1, i.e. make the NMI pending in the TDX module. If there is a further pending NMI in KVM, collapse it to the one pending in the TDX module. VMM can request the TDX module to inject a NMI into a TDX vCPU by setting the PEND_NMI TDVPS field to 1. Following that, VMM can call TDH.VP.ENTER to run the vCPU and the TDX module will attempt to inject the NMI as soon as possible. KVM has the following 3 cases to inject two NMIs when handling simultaneous NMIs and they need to be injected in a back-to-back way. Otherwise, OS kernel may fire a warning about the unknown NMI [1]: K1. One NMI is being handled in the guest and one NMI pending in KVM. KVM requests NMI window exit to inject the pending NMI. K2. Two NMIs are pending in KVM. KVM injects the first NMI and requests NMI window exit to inject the second NMI. K3. A previous NMI needs to be rejected and one NMI pending in KVM. KVM first requests force immediate exit followed by a VM entry to complete the NMI rejection. Then, during the force immediate exit, KVM requests NMI window exit to inject the pending NMI. For TDX, PEND_NMI TDVPS field is a 1-bit field, i.e. KVM can only pend one NMI in the TDX module. Also, the vCPU state is protected, KVM doesn't know the NMI blocking states of TDX vCPU, KVM has to assume NMI is always unmasked and allowed. When KVM sees PEND_NMI is 1 after a TD exit, it means the previous NMI needs to be re-injected. Based on KVM's NMI handling flow, there are following 6 cases: In NMI handler TDX module KVM T1. No PEND_NMI=0 1 pending NMI T2. No PEND_NMI=0 2 pending NMIs T3. No PEND_NMI=1 1 pending NMI T4. Yes PEND_NMI=0 1 pending NMI T5. Yes PEND_NMI=0 2 pending NMIs T6. Yes PEND_NMI=1 1 pending NMI K1 is mapped to T4. K2 is mapped to T2 or T5. K3 is mapped to T3 or T6. Note: KVM doesn't know whether NMI is blocked by a NMI or not, case T5 and T6 can happen. When handling pending NMI in KVM for TDX guest, what KVM can do is to add a pending NMI in TDX module when PEND_NMI is 0. T1 and T4 can be handled by this way. However, TDX doesn't allow KVM to request NMI window exit directly, if PEND_NMI is already set and there is still pending NMI in KVM, the only way KVM could try is to request a force immediate exit. But for case T5 and T6, force immediate exit will result in infinite loop because force immediate exit makes it no progress in the NMI handler, so that the pending NMI in the TDX module can never be injected. Considering on X86 bare metal, multiple NMIs could collapse into one NMI, e.g. when NMI is blocked by SMI. It's OS's responsibility to poll all NMI sources in the NMI handler to avoid missing handling of some NMI events. Based on that, for the above 3 cases (K1-K3), only case K1 must inject the second NMI because the guest NMI handler may have already polled some of the NMI sources, which could include the source of the pending NMI, the pending NMI must be injected to avoid the lost of NMI. For case K2 and K3, the guest OS will poll all NMI sources (including the sources caused by the second NMI and further NMI collapsed) when the delivery of the first NMI, KVM doesn't have the necessity to inject the second NMI. To handle the NMI injection properly for TDX, there are two options: - Option 1: Modify the KVM's NMI handling common code, to collapse the second pending NMI for K2 and K3. - Option 2: Do it in TDX specific way. When the previous NMI is still pending in the TDX module, i.e. it has not been delivered to TDX guest yet, collapse the pending NMI in KVM into the previous one. This patch goes with option 2 because it is simple and doesn't impact other VM types. Option 1 may need more discussions. This is the first need to access vCPU scope metadata in the "management" class. Make needed accessors available. [1] https://lore.kernel.org/all/1317409584-23662-5-git-send-email-dzickus@redhat.com/ Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20250222014757.897978-8-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-22 09:47:48 +08:00
void tdx_inject_nmi(struct kvm_vcpu *vcpu);
KVM: TDX: Add a place holder to handle TDX VM exit Introduce the wiring for handling TDX VM exits by implementing the callbacks .get_exit_info(), .get_entry_info(), and .handle_exit(). Additionally, add error handling during the TDX VM exit flow, and add a place holder to handle various exit reasons. Store VMX exit reason and exit qualification in struct vcpu_vt for TDX, so that TDX/VMX can use the same helpers to get exit reason and exit qualification. Store extended exit qualification and exit GPA info in struct vcpu_tdx because they are used by TDX code only. Contention Handling: The TDH.VP.ENTER operation may contend with TDH.MEM.* operations due to secure EPT or TD EPOCH. If the contention occurs, the return value will have TDX_OPERAND_BUSY set, prompting the vCPU to attempt re-entry into the guest with EXIT_FASTPATH_EXIT_HANDLED, not EXIT_FASTPATH_REENTER_GUEST, so that the interrupts pending during IN_GUEST_MODE can be delivered for sure. Otherwise, the requester of KVM_REQ_OUTSIDE_GUEST_MODE may be blocked endlessly. Error Handling: - TDX_SW_ERROR: This includes #UD caused by SEAMCALL instruction if the CPU isn't in VMX operation, #GP caused by SEAMCALL instruction when TDX isn't enabled by the BIOS, and TDX_SEAMCALL_VMFAILINVALID when SEAM firmware is not loaded or disabled. - TDX_ERROR: This indicates some check failed in the TDX module, preventing the vCPU from running. - Failed VM Entry: Exit to userspace with KVM_EXIT_FAIL_ENTRY. Handle it separately before handling TDX_NON_RECOVERABLE because when off-TD debug is not enabled, TDX_NON_RECOVERABLE is set. - TDX_NON_RECOVERABLE: Set by the TDX module when the error is non-recoverable, indicating that the TDX guest is dead or the vCPU is disabled. A special case is triple fault, which also sets TDX_NON_RECOVERABLE but exits to userspace with KVM_EXIT_SHUTDOWN, aligning with the VMX case. - Any unhandled VM exit reason will also return to userspace with KVM_EXIT_INTERNAL_ERROR. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Chao Gao <chao.gao@intel.com> Message-ID: <20250222014225.897298-4-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-06 13:27:04 -05:00
void tdx_get_exit_info(struct kvm_vcpu *vcpu, u32 *reason,
u64 *info1, u64 *info2, u32 *intr_info, u32 *error_code);
KVM: TDX: Implement callbacks for MSR operations Add functions to implement MSR related callbacks, .set_msr(), .get_msr(), and .has_emulated_msr(), for preparation of handling hypercalls from TDX guest for PV RDMSR and WRMSR. Ignore KVM_REQ_MSR_FILTER_CHANGED for TDX. There are three classes of MSR virtualization for TDX. - Non-configurable: TDX module directly virtualizes it. VMM can't configure it, the value set by KVM_SET_MSRS is ignored. - Configurable: TDX module directly virtualizes it. VMM can configure it at VM creation time. The value set by KVM_SET_MSRS is used. - #VE case: TDX guest would issue TDG.VP.VMCALL<INSTRUCTION.{WRMSR,RDMSR}> and VMM handles the MSR hypercall. The value set by KVM_SET_MSRS is used. For the MSRs belonging to the #VE case, the TDX module injects #VE to the TDX guest upon RDMSR or WRMSR. The exact list of such MSRs is defined in TDX Module ABI Spec. Upon #VE, the TDX guest may call TDG.VP.VMCALL<INSTRUCTION.{WRMSR,RDMSR}>, which are defined in GHCI (Guest-Host Communication Interface) so that the host VMM (e.g. KVM) can virtualize the MSRs. TDX doesn't allow VMM to configure interception of MSR accesses. Ignore KVM_REQ_MSR_FILTER_CHANGED for TDX guest. If the userspace has set any MSR filters, it will be applied when handling TDG.VP.VMCALL<INSTRUCTION.{WRMSR,RDMSR}> in a later patch. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Binbin Wu <binbin.wu@linux.intel.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20250227012021.1778144-9-binbin.wu@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-27 09:20:09 +08:00
bool tdx_has_emulated_msr(u32 index);
int tdx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
int tdx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr);
int tdx_vcpu_ioctl(struct kvm_vcpu *vcpu, void __user *argp);
KVM: TDX: Add load_mmu_pgd method for TDX TDX uses two EPT pointers, one for the private half of the GPA space and one for the shared half. The private half uses the normal EPT_POINTER vmcs field, which is managed in a special way by the TDX module. For TDX, KVM is not allowed to operate on it directly. The shared half uses a new SHARED_EPT_POINTER field and will be managed by the conventional MMU management operations that operate directly on the EPT root. This means for TDX the .load_mmu_pgd() operation will need to know to use the SHARED_EPT_POINTER field instead of the normal one. Add a new wrapper in x86 ops for load_mmu_pgd() that either directs the write to the existing vmx implementation or a TDX one. tdx_load_mmu_pgd() is so much simpler than vmx_load_mmu_pgd() since for the TDX mode of operation, EPT will always be used and KVM does not need to be involved in virtualization of CR3 behavior. So tdx_load_mmu_pgd() can simply write to SHARED_EPT_POINTER. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Co-developed-by: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Co-developed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20241112073601.22084-1-yan.y.zhao@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-11-12 15:36:01 +08:00
KVM: TDX: Handle TLB tracking for TDX Handle TLB tracking for TDX by introducing function tdx_track() for private memory TLB tracking and implementing flush_tlb* hooks to flush TLBs for shared memory. Introduce function tdx_track() to do TLB tracking on private memory, which basically does two things: calling TDH.MEM.TRACK to increase TD epoch and kicking off all vCPUs. The private EPT will then be flushed when each vCPU re-enters the TD. This function is unused temporarily in this patch and will be called on a page-by-page basis on removal of private guest page in a later patch. In earlier revisions, tdx_track() relied on an atomic counter to coordinate the synchronization between the actions of kicking off vCPUs, incrementing the TD epoch, and the vCPUs waiting for the incremented TD epoch after being kicked off. However, the core MMU only actually needs to call tdx_track() while aleady under a write mmu_lock. So this sychnonization can be made to be unneeded. vCPUs are kicked off only after the successful execution of TDH.MEM.TRACK, eliminating the need for vCPUs to wait for TDH.MEM.TRACK completion after being kicked off. tdx_track() is therefore able to send requests KVM_REQ_OUTSIDE_GUEST_MODE rather than KVM_REQ_TLB_FLUSH. Hooks for flush_remote_tlb and flush_remote_tlbs_range are not necessary for TDX, as tdx_track() will handle TLB tracking of private memory on page-by-page basis when private guest pages are removed. There is no need to invoke tdx_track() again in kvm_flush_remote_tlbs() even after changes to the mirrored page table. For hooks flush_tlb_current and flush_tlb_all, which are invoked during kvm_mmu_load() and vcpu load for normal VMs, let VMM to flush all EPTs in the two hooks for simplicity, since TDX does not depend on the two hooks to notify TDX module to flush private EPT in those cases. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Co-developed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Message-ID: <20241112073753.22228-1-yan.y.zhao@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-11-12 15:37:53 +08:00
void tdx_flush_tlb_current(struct kvm_vcpu *vcpu);
void tdx_flush_tlb_all(struct kvm_vcpu *vcpu);
KVM: TDX: Add load_mmu_pgd method for TDX TDX uses two EPT pointers, one for the private half of the GPA space and one for the shared half. The private half uses the normal EPT_POINTER vmcs field, which is managed in a special way by the TDX module. For TDX, KVM is not allowed to operate on it directly. The shared half uses a new SHARED_EPT_POINTER field and will be managed by the conventional MMU management operations that operate directly on the EPT root. This means for TDX the .load_mmu_pgd() operation will need to know to use the SHARED_EPT_POINTER field instead of the normal one. Add a new wrapper in x86 ops for load_mmu_pgd() that either directs the write to the existing vmx implementation or a TDX one. tdx_load_mmu_pgd() is so much simpler than vmx_load_mmu_pgd() since for the TDX mode of operation, EPT will always be used and KVM does not need to be involved in virtualization of CR3 behavior. So tdx_load_mmu_pgd() can simply write to SHARED_EPT_POINTER. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Co-developed-by: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Co-developed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Yan Zhao <yan.y.zhao@intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20241112073601.22084-1-yan.y.zhao@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-11-12 15:36:01 +08:00
void tdx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, int root_level);
int tdx_gmem_private_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn);
#endif
KVM: VMX: Move out vmx_x86_ops to 'main.c' to dispatch VMX and TDX KVM accesses Virtual Machine Control Structure (VMCS) with VMX instructions to operate on VM. TDX doesn't allow VMM to operate VMCS directly. Instead, TDX has its own data structures, and TDX SEAMCALL APIs for VMM to indirectly operate those data structures. This means we must have a TDX version of kvm_x86_ops. The existing global struct kvm_x86_ops already defines an interface which can be adapted to TDX, but kvm_x86_ops is a system-wide, not per-VM structure. To allow VMX to coexist with TDs, the kvm_x86_ops callbacks will have wrappers "if (tdx) tdx_op() else vmx_op()" to pick VMX or TDX at run time. To split the runtime switch, the VMX implementation, and the TDX implementation, add main.c, and move out the vmx_x86_ops hooks in preparation for adding TDX. Use 'vt' for the naming scheme as a nod to VT-x and as a concatenation of VmxTdx. The eventually converted code will look like this: vmx.c: vmx_op() { ... } VMX initialization tdx.c: tdx_op() { ... } TDX initialization x86_ops.h: vmx_op(); tdx_op(); main.c: static vt_op() { if (tdx) tdx_op() else vmx_op() } static struct kvm_x86_ops vt_x86_ops = { .op = vt_op, initialization functions call both VMX and TDX initialization Opportunistically, fix the name inconsistency from vmx_create_vcpu() and vmx_free_vcpu() to vmx_vcpu_create() and vmx_vcpu_free(). Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Message-Id: <e603c317587f933a9d1bee8728c84e4935849c16.1705965634.git.isaku.yamahata@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-03-18 11:39:16 -04:00
#endif /* __KVM_X86_VMX_X86_OPS_H */