Set up CET MSRs, related VM_ENTRY/EXIT control bits and fixed CR4 setting
to enable CET for nested VM.
Note, generally L1 VMM only touches CET VMCS fields when live migration or
vmcs_{read,write}() to the fields happens, so the fields only need to be
synced in these "rare" cases. And here only considers the case that L1 VMM
has set VM_ENTRY_LOAD_CET_STATE in its VMCS vm_entry_controls as it's the
common usage.
Suggested-by: Chao Gao <chao.gao@xxxxxxxxx>
Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx>
---
arch/x86/kvm/vmx/nested.c | 48 +++++++++++++++++++++++++++++++++++++--
arch/x86/kvm/vmx/vmcs12.c | 6 +++++
arch/x86/kvm/vmx/vmcs12.h | 14 +++++++++++-
arch/x86/kvm/vmx/vmx.c | 2 ++
4 files changed, 67 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index d8c32682ca76..965173650542 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -660,6 +660,28 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu,
nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
MSR_IA32_FLUSH_CMD, MSR_TYPE_W);
+ /* Pass CET MSRs to nested VM if L0 and L1 are set to pass-through. */
+ nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
+ MSR_IA32_U_CET, MSR_TYPE_RW);
+
+ nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
+ MSR_IA32_S_CET, MSR_TYPE_RW);
+
+ nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
+ MSR_IA32_PL0_SSP, MSR_TYPE_RW);
+
+ nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
+ MSR_IA32_PL1_SSP, MSR_TYPE_RW);
+
+ nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
+ MSR_IA32_PL2_SSP, MSR_TYPE_RW);
+
+ nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
+ MSR_IA32_PL3_SSP, MSR_TYPE_RW);
+
+ nested_vmx_set_intercept_for_msr(vmx, msr_bitmap_l1, msr_bitmap_l0,
+ MSR_IA32_INT_SSP_TAB, MSR_TYPE_RW);
+
kvm_vcpu_unmap(vcpu, &vmx->nested.msr_bitmap_map, false);
vmx->nested.force_msr_bitmap_recalc = false;
@@ -2469,6 +2491,18 @@ static void prepare_vmcs02_rare(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12)
if (kvm_mpx_supported() && vmx->nested.nested_run_pending &&
(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_BNDCFGS))
vmcs_write64(GUEST_BNDCFGS, vmcs12->guest_bndcfgs);
+
+ if (vmx->nested.nested_run_pending &&
+ (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_CET_STATE)) {
+ if (guest_can_use(&vmx->vcpu, X86_FEATURE_SHSTK)) {
+ vmcs_writel(GUEST_SSP, vmcs12->guest_ssp);
+ vmcs_writel(GUEST_INTR_SSP_TABLE,
+ vmcs12->guest_ssp_tbl);
+ }
+ if (guest_can_use(&vmx->vcpu, X86_FEATURE_SHSTK) ||
+ guest_can_use(&vmx->vcpu, X86_FEATURE_IBT))
+ vmcs_writel(GUEST_S_CET, vmcs12->guest_s_cet);
+ }
}
if (nested_cpu_has_xsaves(vmcs12))
@@ -4300,6 +4334,15 @@ static void sync_vmcs02_to_vmcs12_rare(struct kvm_vcpu *vcpu,
vmcs12->guest_pending_dbg_exceptions =
vmcs_readl(GUEST_PENDING_DBG_EXCEPTIONS);
+ if (guest_can_use(&vmx->vcpu, X86_FEATURE_SHSTK)) {
+ vmcs12->guest_ssp = vmcs_readl(GUEST_SSP);
+ vmcs12->guest_ssp_tbl = vmcs_readl(GUEST_INTR_SSP_TABLE);
+ }
+ if (guest_can_use(&vmx->vcpu, X86_FEATURE_SHSTK) ||
+ guest_can_use(&vmx->vcpu, X86_FEATURE_IBT)) {
+ vmcs12->guest_s_cet = vmcs_readl(GUEST_S_CET);
+ }
+
vmx->nested.need_sync_vmcs02_to_vmcs12_rare = false;
}
@@ -6798,7 +6841,7 @@ static void nested_vmx_setup_exit_ctls(struct vmcs_config *vmcs_conf,
VM_EXIT_HOST_ADDR_SPACE_SIZE |
#endif
VM_EXIT_LOAD_IA32_PAT | VM_EXIT_SAVE_IA32_PAT |
- VM_EXIT_CLEAR_BNDCFGS;
+ VM_EXIT_CLEAR_BNDCFGS | VM_EXIT_LOAD_CET_STATE;
msrs->exit_ctls_high |=
VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR |
VM_EXIT_LOAD_IA32_EFER | VM_EXIT_SAVE_IA32_EFER |
@@ -6820,7 +6863,8 @@ static void nested_vmx_setup_entry_ctls(struct vmcs_config *vmcs_conf,
#ifdef CONFIG_X86_64
VM_ENTRY_IA32E_MODE |
#endif
- VM_ENTRY_LOAD_IA32_PAT | VM_ENTRY_LOAD_BNDCFGS;
+ VM_ENTRY_LOAD_IA32_PAT | VM_ENTRY_LOAD_BNDCFGS |
+ VM_ENTRY_LOAD_CET_STATE;
msrs->entry_ctls_high |=
(VM_ENTRY_ALWAYSON_WITHOUT_TRUE_MSR | VM_ENTRY_LOAD_IA32_EFER |
VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL);
diff --git a/arch/x86/kvm/vmx/vmcs12.c b/arch/x86/kvm/vmx/vmcs12.c
index 106a72c923ca..4233b5ca9461 100644
--- a/arch/x86/kvm/vmx/vmcs12.c
+++ b/arch/x86/kvm/vmx/vmcs12.c
@@ -139,6 +139,9 @@ const unsigned short vmcs12_field_offsets[] = {
FIELD(GUEST_PENDING_DBG_EXCEPTIONS, guest_pending_dbg_exceptions),
FIELD(GUEST_SYSENTER_ESP, guest_sysenter_esp),
FIELD(GUEST_SYSENTER_EIP, guest_sysenter_eip),
+ FIELD(GUEST_S_CET, guest_s_cet),
+ FIELD(GUEST_SSP, guest_ssp),
+ FIELD(GUEST_INTR_SSP_TABLE, guest_ssp_tbl),
FIELD(HOST_CR0, host_cr0),
FIELD(HOST_CR3, host_cr3),
FIELD(HOST_CR4, host_cr4),
@@ -151,5 +154,8 @@ const unsigned short vmcs12_field_offsets[] = {
FIELD(HOST_IA32_SYSENTER_EIP, host_ia32_sysenter_eip),
FIELD(HOST_RSP, host_rsp),
FIELD(HOST_RIP, host_rip),
+ FIELD(HOST_S_CET, host_s_cet),
+ FIELD(HOST_SSP, host_ssp),
+ FIELD(HOST_INTR_SSP_TABLE, host_ssp_tbl),
};
const unsigned int nr_vmcs12_fields = ARRAY_SIZE(vmcs12_field_offsets);
diff --git a/arch/x86/kvm/vmx/vmcs12.h b/arch/x86/kvm/vmx/vmcs12.h
index 01936013428b..3884489e7f7e 100644
--- a/arch/x86/kvm/vmx/vmcs12.h
+++ b/arch/x86/kvm/vmx/vmcs12.h
@@ -117,7 +117,13 @@ struct __packed vmcs12 {
natural_width host_ia32_sysenter_eip;
natural_width host_rsp;
natural_width host_rip;
- natural_width paddingl[8]; /* room for future expansion */
+ natural_width host_s_cet;
+ natural_width host_ssp;
+ natural_width host_ssp_tbl;
+ natural_width guest_s_cet;
+ natural_width guest_ssp;
+ natural_width guest_ssp_tbl;
+ natural_width paddingl[2]; /* room for future expansion */
u32 pin_based_vm_exec_control;
u32 cpu_based_vm_exec_control;
u32 exception_bitmap;
@@ -292,6 +298,12 @@ static inline void vmx_check_vmcs12_offsets(void)
CHECK_OFFSET(host_ia32_sysenter_eip, 656);
CHECK_OFFSET(host_rsp, 664);
CHECK_OFFSET(host_rip, 672);
+ CHECK_OFFSET(host_s_cet, 680);
+ CHECK_OFFSET(host_ssp, 688);
+ CHECK_OFFSET(host_ssp_tbl, 696);
+ CHECK_OFFSET(guest_s_cet, 704);
+ CHECK_OFFSET(guest_ssp, 712);
+ CHECK_OFFSET(guest_ssp_tbl, 720);
CHECK_OFFSET(pin_based_vm_exec_control, 744);
CHECK_OFFSET(cpu_based_vm_exec_control, 748);
CHECK_OFFSET(exception_bitmap, 752);
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index a1aae8709939..947028ff2e25 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7734,6 +7734,8 @@ static void nested_vmx_cr_fixed1_bits_update(struct kvm_vcpu *vcpu)
cr4_fixed1_update(X86_CR4_PKE, ecx, feature_bit(PKU));
cr4_fixed1_update(X86_CR4_UMIP, ecx, feature_bit(UMIP));
cr4_fixed1_update(X86_CR4_LA57, ecx, feature_bit(LA57));
+ cr4_fixed1_update(X86_CR4_CET, ecx, feature_bit(SHSTK));
+ cr4_fixed1_update(X86_CR4_CET, edx, feature_bit(IBT));
#undef cr4_fixed1_update
}
--
2.27.0
