From: Bandan Das <bsd@redhat.com>
Date: Thu, 3 Aug 2017 15:54:41 -0400
Subject: KVM: vmx: Enable VMFUNCs
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Patch-mainline: v4.14-rc1
Git-commit: 2a499e49c2ecc4ce5e11cc876a194fb16f05a66b
References: bsc#1077761
Enable VMFUNC in the secondary execution controls. This simplifies the
changes necessary to expose it to nested hypervisors. VMFUNCs still
cause #UD when invoked.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Bandan Das <bsd@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
arch/x86/include/asm/vmx.h | 3 +++
arch/x86/kvm/vmx.c | 22 +++++++++++++++++++++-
2 files changed, 24 insertions(+), 1 deletion(-)
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -72,6 +72,7 @@
#define SECONDARY_EXEC_PAUSE_LOOP_EXITING 0x00000400
#define SECONDARY_EXEC_RDRAND 0x00000800
#define SECONDARY_EXEC_ENABLE_INVPCID 0x00001000
+#define SECONDARY_EXEC_ENABLE_VMFUNC 0x00002000
#define SECONDARY_EXEC_SHADOW_VMCS 0x00004000
#define SECONDARY_EXEC_RDSEED 0x00010000
#define SECONDARY_EXEC_ENABLE_PML 0x00020000
@@ -187,6 +188,8 @@
APIC_ACCESS_ADDR_HIGH = 0x00002015,
POSTED_INTR_DESC_ADDR = 0x00002016,
POSTED_INTR_DESC_ADDR_HIGH = 0x00002017,
+ VM_FUNCTION_CONTROL = 0x00002018,
+ VM_FUNCTION_CONTROL_HIGH = 0x00002019,
EPT_POINTER = 0x0000201a,
EPT_POINTER_HIGH = 0x0000201b,
EOI_EXIT_BITMAP0 = 0x0000201c,
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1295,6 +1295,12 @@
SECONDARY_EXEC_TSC_SCALING;
}
+static inline bool cpu_has_vmx_vmfunc(void)
+{
+ return vmcs_config.cpu_based_2nd_exec_ctrl &
+ SECONDARY_EXEC_ENABLE_VMFUNC;
+}
+
static inline bool report_flexpriority(void)
{
return flexpriority_enabled;
@@ -3618,7 +3624,8 @@
SECONDARY_EXEC_SHADOW_VMCS |
SECONDARY_EXEC_XSAVES |
SECONDARY_EXEC_ENABLE_PML |
- SECONDARY_EXEC_TSC_SCALING;
+ SECONDARY_EXEC_TSC_SCALING |
+ SECONDARY_EXEC_ENABLE_VMFUNC;
if (adjust_vmx_controls(min2, opt2,
MSR_IA32_VMX_PROCBASED_CTLS2,
&_cpu_based_2nd_exec_control) < 0)
@@ -5328,6 +5335,9 @@
vmcs_writel(HOST_GS_BASE, 0); /* 22.2.4 */
#endif
+ if (cpu_has_vmx_vmfunc())
+ vmcs_write64(VM_FUNCTION_CONTROL, 0);
+
vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0);
vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, 0);
vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host));
@@ -7818,6 +7828,12 @@
return 1;
}
+static int handle_vmfunc(struct kvm_vcpu *vcpu)
+{
+ kvm_queue_exception(vcpu, UD_VECTOR);
+ return 1;
+}
+
/*
* The exit handlers return 1 if the exit was handled fully and guest execution
* may resume. Otherwise they set the kvm_run parameter to indicate what needs
@@ -7868,6 +7884,7 @@
[EXIT_REASON_XSAVES] = handle_xsaves,
[EXIT_REASON_XRSTORS] = handle_xrstors,
[EXIT_REASON_PML_FULL] = handle_pml_full,
+ [EXIT_REASON_VMFUNC] = handle_vmfunc,
[EXIT_REASON_PREEMPTION_TIMER] = handle_preemption_timer,
};
@@ -8204,6 +8221,9 @@
case EXIT_REASON_PML_FULL:
/* We emulate PML support to L1. */
return false;
+ case EXIT_REASON_VMFUNC:
+ /* VM functions are emulated through L2->L0 vmexits. */
+ return false;
default:
return true;
}