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-rw-r--r--arch/x86/kvm/cpuid.c1
-rw-r--r--arch/x86/kvm/emulate.c104
-rw-r--r--arch/x86/kvm/svm.c11
-rw-r--r--arch/x86/kvm/vmx.c72
-rw-r--r--arch/x86/kvm/x86.c6
5 files changed, 141 insertions, 53 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 0489ffc3d..768a765c4 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -680,6 +680,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
g_phys_as = phys_as;
entry->eax = g_phys_as | (virt_as << 8);
+ entry->ecx &= ~(GENMASK(31, 16) | GENMASK(11, 8));
entry->edx = 0;
/*
* IBRS, IBPB and VIRT_SSBD aren't necessarily present in
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 25bdd0696..0cb75d29e 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -759,8 +759,7 @@ static int linearize(struct x86_emulate_ctxt *ctxt,
ctxt->mode, linear);
}
-static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst,
- enum x86emul_mode mode)
+static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
{
ulong linear;
int rc;
@@ -770,41 +769,71 @@ static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst,
if (ctxt->op_bytes != sizeof(unsigned long))
addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1);
- rc = __linearize(ctxt, addr, &max_size, 1, false, true, mode, &linear);
+ rc = __linearize(ctxt, addr, &max_size, 1, false, true, ctxt->mode, &linear);
if (rc == X86EMUL_CONTINUE)
ctxt->_eip = addr.ea;
return rc;
}
+static inline int emulator_recalc_and_set_mode(struct x86_emulate_ctxt *ctxt)
+{
+ u64 efer;
+ struct desc_struct cs;
+ u16 selector;
+ u32 base3;
+
+ ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
+
+ if (!(ctxt->ops->get_cr(ctxt, 0) & X86_CR0_PE)) {
+ /* Real mode. cpu must not have long mode active */
+ if (efer & EFER_LMA)
+ return X86EMUL_UNHANDLEABLE;
+ ctxt->mode = X86EMUL_MODE_REAL;
+ return X86EMUL_CONTINUE;
+ }
+
+ if (ctxt->eflags & X86_EFLAGS_VM) {
+ /* Protected/VM86 mode. cpu must not have long mode active */
+ if (efer & EFER_LMA)
+ return X86EMUL_UNHANDLEABLE;
+ ctxt->mode = X86EMUL_MODE_VM86;
+ return X86EMUL_CONTINUE;
+ }
+
+ if (!ctxt->ops->get_segment(ctxt, &selector, &cs, &base3, VCPU_SREG_CS))
+ return X86EMUL_UNHANDLEABLE;
+
+ if (efer & EFER_LMA) {
+ if (cs.l) {
+ /* Proper long mode */
+ ctxt->mode = X86EMUL_MODE_PROT64;
+ } else if (cs.d) {
+ /* 32 bit compatibility mode*/
+ ctxt->mode = X86EMUL_MODE_PROT32;
+ } else {
+ ctxt->mode = X86EMUL_MODE_PROT16;
+ }
+ } else {
+ /* Legacy 32 bit / 16 bit mode */
+ ctxt->mode = cs.d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
+ }
+
+ return X86EMUL_CONTINUE;
+}
+
static inline int assign_eip_near(struct x86_emulate_ctxt *ctxt, ulong dst)
{
- return assign_eip(ctxt, dst, ctxt->mode);
+ return assign_eip(ctxt, dst);
}
-static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst,
- const struct desc_struct *cs_desc)
+static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst)
{
- enum x86emul_mode mode = ctxt->mode;
- int rc;
+ int rc = emulator_recalc_and_set_mode(ctxt);
-#ifdef CONFIG_X86_64
- if (ctxt->mode >= X86EMUL_MODE_PROT16) {
- if (cs_desc->l) {
- u64 efer = 0;
+ if (rc != X86EMUL_CONTINUE)
+ return rc;
- ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
- if (efer & EFER_LMA)
- mode = X86EMUL_MODE_PROT64;
- } else
- mode = X86EMUL_MODE_PROT32; /* temporary value */
- }
-#endif
- if (mode == X86EMUL_MODE_PROT16 || mode == X86EMUL_MODE_PROT32)
- mode = cs_desc->d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
- rc = assign_eip(ctxt, dst, mode);
- if (rc == X86EMUL_CONTINUE)
- ctxt->mode = mode;
- return rc;
+ return assign_eip(ctxt, dst);
}
static inline int jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
@@ -1975,7 +2004,7 @@ static int em_pop_sreg(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- if (ctxt->modrm_reg == VCPU_SREG_SS)
+ if (seg == VCPU_SREG_SS)
ctxt->interruptibility = KVM_X86_SHADOW_INT_MOV_SS;
if (ctxt->op_bytes > 2)
rsp_increment(ctxt, ctxt->op_bytes - 2);
@@ -2192,7 +2221,7 @@ static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
+ rc = assign_eip_far(ctxt, ctxt->src.val);
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -2273,7 +2302,7 @@ static int em_ret_far(struct x86_emulate_ctxt *ctxt)
&new_desc);
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, eip, &new_desc);
+ rc = assign_eip_far(ctxt, eip);
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -2895,6 +2924,7 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt)
ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
ctxt->_eip = rdx;
+ ctxt->mode = usermode;
*reg_write(ctxt, VCPU_REGS_RSP) = rcx;
return X86EMUL_CONTINUE;
@@ -3491,7 +3521,7 @@ static int em_call_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
+ rc = assign_eip_far(ctxt, ctxt->src.val);
if (rc != X86EMUL_CONTINUE)
goto fail;
@@ -3638,11 +3668,25 @@ static int em_movbe(struct x86_emulate_ctxt *ctxt)
static int em_cr_write(struct x86_emulate_ctxt *ctxt)
{
- if (ctxt->ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val))
+ int cr_num = ctxt->modrm_reg;
+ int r;
+
+ if (ctxt->ops->set_cr(ctxt, cr_num, ctxt->src.val))
return emulate_gp(ctxt, 0);
/* Disable writeback. */
ctxt->dst.type = OP_NONE;
+
+ if (cr_num == 0) {
+ /*
+ * CR0 write might have updated CR0.PE and/or CR0.PG
+ * which can affect the cpu's execution mode.
+ */
+ r = emulator_recalc_and_set_mode(ctxt);
+ if (r != X86EMUL_CONTINUE)
+ return r;
+ }
+
return X86EMUL_CONTINUE;
}
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index e1492a67e..cd3432df0 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -50,6 +50,7 @@
#include <asm/kvm_para.h>
#include <asm/irq_remapping.h>
#include <asm/spec-ctrl.h>
+#include <asm/cpu_device_id.h>
#include <asm/virtext.h>
#include "trace.h"
@@ -4154,9 +4155,9 @@ static int svm_get_msr_feature(struct kvm_msr_entry *msr)
msr->data = 0;
switch (msr->index) {
- case MSR_F10H_DECFG:
- if (boot_cpu_has(X86_FEATURE_LFENCE_RDTSC))
- msr->data |= MSR_F10H_DECFG_LFENCE_SERIALIZE;
+ case MSR_AMD64_DE_CFG:
+ if (cpu_feature_enabled(X86_FEATURE_LFENCE_RDTSC))
+ msr->data |= MSR_AMD64_DE_CFG_LFENCE_SERIALIZE;
break;
default:
return 1;
@@ -4258,7 +4259,7 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
msr_info->data = 0x1E;
}
break;
- case MSR_F10H_DECFG:
+ case MSR_AMD64_DE_CFG:
msr_info->data = svm->msr_decfg;
break;
default:
@@ -4445,7 +4446,7 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
case MSR_VM_IGNNE:
vcpu_unimpl(vcpu, "unimplemented wrmsr: 0x%x data 0x%llx\n", ecx, data);
break;
- case MSR_F10H_DECFG: {
+ case MSR_AMD64_DE_CFG: {
struct kvm_msr_entry msr_entry;
msr_entry.index = msr->index;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 20ce79458..9bb696d73 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -41,6 +41,7 @@
#include <asm/asm.h>
#include <asm/cpu.h>
+#include <asm/cpu_device_id.h>
#include <asm/io.h>
#include <asm/desc.h>
#include <asm/vmx.h>
@@ -2132,9 +2133,9 @@ static __always_inline void vmx_disable_fb_clear(struct vcpu_vmx *vmx)
if (!vmx->disable_fb_clear)
return;
- rdmsrl(MSR_IA32_MCU_OPT_CTRL, msr);
+ msr = __rdmsr(MSR_IA32_MCU_OPT_CTRL);
msr |= FB_CLEAR_DIS;
- wrmsrl(MSR_IA32_MCU_OPT_CTRL, msr);
+ native_wrmsrl(MSR_IA32_MCU_OPT_CTRL, msr);
/* Cache the MSR value to avoid reading it later */
vmx->msr_ia32_mcu_opt_ctrl = msr;
}
@@ -2145,7 +2146,7 @@ static __always_inline void vmx_enable_fb_clear(struct vcpu_vmx *vmx)
return;
vmx->msr_ia32_mcu_opt_ctrl &= ~FB_CLEAR_DIS;
- wrmsrl(MSR_IA32_MCU_OPT_CTRL, vmx->msr_ia32_mcu_opt_ctrl);
+ native_wrmsrl(MSR_IA32_MCU_OPT_CTRL, vmx->msr_ia32_mcu_opt_ctrl);
}
static void vmx_update_fb_clear_dis(struct kvm_vcpu *vcpu, struct vcpu_vmx *vmx)
@@ -10759,10 +10760,35 @@ static void vmx_update_hv_timer(struct kvm_vcpu *vcpu)
vmx->loaded_vmcs->hv_timer_armed = false;
}
+u64 __always_inline vmx_spec_ctrl_restore_host(struct vcpu_vmx *vmx)
+{
+ u64 guestval, hostval = this_cpu_read(x86_spec_ctrl_current);
+
+ if (!cpu_feature_enabled(X86_FEATURE_MSR_SPEC_CTRL))
+ return 0;
+
+ guestval = __rdmsr(MSR_IA32_SPEC_CTRL);
+
+ /*
+ *
+ * For legacy IBRS, the IBRS bit always needs to be written after
+ * transitioning from a less privileged predictor mode, regardless of
+ * whether the guest/host values differ.
+ */
+ if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS) ||
+ guestval != hostval)
+ native_wrmsrl(MSR_IA32_SPEC_CTRL, hostval);
+
+ barrier_nospec();
+
+ return guestval;
+}
+
static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
unsigned long cr3, cr4, evmcs_rsp;
+ u64 spec_ctrl;
/* Record the guest's net vcpu time for enforced NMI injections. */
if (unlikely(!enable_vnmi &&
@@ -10988,9 +11014,24 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
#endif
);
- /* Eliminate branch target predictions from guest mode */
+ /*
+ * IMPORTANT: RSB filling and SPEC_CTRL handling must be done before
+ * the first unbalanced RET after vmexit!
+ *
+ * For retpoline or IBRS, RSB filling is needed to prevent poisoned RSB
+ * entries and (in some cases) RSB underflow.
+ *
+ * eIBRS has its own protection against poisoned RSB, so it doesn't
+ * need the RSB filling sequence. But it does need to be enabled, and a
+ * single call to retire, before the first unbalanced RET.
+ *
+ * So no RETs before vmx_spec_ctrl_restore_host() below.
+ */
vmexit_fill_RSB();
+ /* Save this for below */
+ spec_ctrl = vmx_spec_ctrl_restore_host(vmx);
+
vmx_enable_fb_clear(vmx);
/*
@@ -11009,9 +11050,7 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
* save it.
*/
if (unlikely(!msr_write_intercepted(vcpu, MSR_IA32_SPEC_CTRL)))
- vmx->spec_ctrl = native_read_msr(MSR_IA32_SPEC_CTRL);
-
- x86_spec_ctrl_restore_host(vmx->spec_ctrl, 0);
+ vmx->spec_ctrl = spec_ctrl;
/* All fields are clean at this point */
if (static_branch_unlikely(&enable_evmcs))
@@ -13276,14 +13315,6 @@ static void prepare_vmcs12(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
*/
vmcs12_save_pending_event(vcpu, vmcs12);
}
-
- /*
- * Drop what we picked up for L2 via vmx_complete_interrupts. It is
- * preserved above and would only end up incorrectly in L1.
- */
- vcpu->arch.nmi_injected = false;
- kvm_clear_exception_queue(vcpu);
- kvm_clear_interrupt_queue(vcpu);
}
/*
@@ -13617,6 +13648,17 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason,
nested_vmx_abort(vcpu, VMX_ABORT_SAVE_GUEST_MSR_FAIL);
}
+ /*
+ * Drop events/exceptions that were queued for re-injection to L2
+ * (picked up via vmx_complete_interrupts()), as well as exceptions
+ * that were pending for L2. Note, this must NOT be hoisted above
+ * prepare_vmcs12(), events/exceptions queued for re-injection need to
+ * be captured in vmcs12 (see vmcs12_save_pending_event()).
+ */
+ vcpu->arch.nmi_injected = false;
+ kvm_clear_exception_queue(vcpu);
+ kvm_clear_interrupt_queue(vcpu);
+
vmx_switch_vmcs(vcpu, &vmx->vmcs01);
vm_entry_controls_reset_shadow(vmx);
vm_exit_controls_reset_shadow(vmx);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index be4697d91..8fe615df8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1156,7 +1156,7 @@ static u32 msr_based_features[] = {
MSR_IA32_VMX_EPT_VPID_CAP,
MSR_IA32_VMX_VMFUNC,
- MSR_F10H_DECFG,
+ MSR_AMD64_DE_CFG,
MSR_IA32_UCODE_REV,
MSR_IA32_ARCH_CAPABILITIES,
};
@@ -9736,9 +9736,9 @@ void kvm_arch_end_assignment(struct kvm *kvm)
}
EXPORT_SYMBOL_GPL(kvm_arch_end_assignment);
-bool kvm_arch_has_assigned_device(struct kvm *kvm)
+bool noinstr kvm_arch_has_assigned_device(struct kvm *kvm)
{
- return atomic_read(&kvm->arch.assigned_device_count);
+ return arch_atomic_read(&kvm->arch.assigned_device_count);
}
EXPORT_SYMBOL_GPL(kvm_arch_has_assigned_device);