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-rw-r--r--arch/x86/kvm/vmx.c90
1 files changed, 89 insertions, 1 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 7042b6921961..7dc599630430 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -484,6 +484,64 @@ static inline struct vcpu_vmx *to_vmx(struct kvm_vcpu *vcpu)
#define FIELD64(number, name) [number] = VMCS12_OFFSET(name), \
[number##_HIGH] = VMCS12_OFFSET(name)+4
+
+static const unsigned long shadow_read_only_fields[] = {
+ /*
+ * We do NOT shadow fields that are modified when L0
+ * traps and emulates any vmx instruction (e.g. VMPTRLD,
+ * VMXON...) executed by L1.
+ * For example, VM_INSTRUCTION_ERROR is read
+ * by L1 if a vmx instruction fails (part of the error path).
+ * Note the code assumes this logic. If for some reason
+ * we start shadowing these fields then we need to
+ * force a shadow sync when L0 emulates vmx instructions
+ * (e.g. force a sync if VM_INSTRUCTION_ERROR is modified
+ * by nested_vmx_failValid)
+ */
+ VM_EXIT_REASON,
+ VM_EXIT_INTR_INFO,
+ VM_EXIT_INSTRUCTION_LEN,
+ IDT_VECTORING_INFO_FIELD,
+ IDT_VECTORING_ERROR_CODE,
+ VM_EXIT_INTR_ERROR_CODE,
+ EXIT_QUALIFICATION,
+ GUEST_LINEAR_ADDRESS,
+ GUEST_PHYSICAL_ADDRESS
+};
+static const int max_shadow_read_only_fields =
+ ARRAY_SIZE(shadow_read_only_fields);
+
+static const unsigned long shadow_read_write_fields[] = {
+ GUEST_RIP,
+ GUEST_RSP,
+ GUEST_CR0,
+ GUEST_CR3,
+ GUEST_CR4,
+ GUEST_INTERRUPTIBILITY_INFO,
+ GUEST_RFLAGS,
+ GUEST_CS_SELECTOR,
+ GUEST_CS_AR_BYTES,
+ GUEST_CS_LIMIT,
+ GUEST_CS_BASE,
+ GUEST_ES_BASE,
+ CR0_GUEST_HOST_MASK,
+ CR0_READ_SHADOW,
+ CR4_READ_SHADOW,
+ TSC_OFFSET,
+ EXCEPTION_BITMAP,
+ CPU_BASED_VM_EXEC_CONTROL,
+ VM_ENTRY_EXCEPTION_ERROR_CODE,
+ VM_ENTRY_INTR_INFO_FIELD,
+ VM_ENTRY_INSTRUCTION_LEN,
+ VM_ENTRY_EXCEPTION_ERROR_CODE,
+ HOST_FS_BASE,
+ HOST_GS_BASE,
+ HOST_FS_SELECTOR,
+ HOST_GS_SELECTOR
+};
+static const int max_shadow_read_write_fields =
+ ARRAY_SIZE(shadow_read_write_fields);
+
static const unsigned short vmcs_field_to_offset_table[] = {
FIELD(VIRTUAL_PROCESSOR_ID, virtual_processor_id),
FIELD(GUEST_ES_SELECTOR, guest_es_selector),
@@ -675,6 +733,8 @@ static unsigned long *vmx_msr_bitmap_legacy;
static unsigned long *vmx_msr_bitmap_longmode;
static unsigned long *vmx_msr_bitmap_legacy_x2apic;
static unsigned long *vmx_msr_bitmap_longmode_x2apic;
+static unsigned long *vmx_vmread_bitmap;
+static unsigned long *vmx_vmwrite_bitmap;
static bool cpu_has_load_ia32_efer;
static bool cpu_has_load_perf_global_ctrl;
@@ -4128,6 +4188,10 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
vmcs_write64(IO_BITMAP_A, __pa(vmx_io_bitmap_a));
vmcs_write64(IO_BITMAP_B, __pa(vmx_io_bitmap_b));
+ if (enable_shadow_vmcs) {
+ vmcs_write64(VMREAD_BITMAP, __pa(vmx_vmread_bitmap));
+ vmcs_write64(VMWRITE_BITMAP, __pa(vmx_vmwrite_bitmap));
+ }
if (cpu_has_vmx_msr_bitmap())
vmcs_write64(MSR_BITMAP, __pa(vmx_msr_bitmap_legacy));
@@ -7941,6 +8005,24 @@ static int __init vmx_init(void)
(unsigned long *)__get_free_page(GFP_KERNEL);
if (!vmx_msr_bitmap_longmode_x2apic)
goto out4;
+ vmx_vmread_bitmap = (unsigned long *)__get_free_page(GFP_KERNEL);
+ if (!vmx_vmread_bitmap)
+ goto out5;
+
+ vmx_vmwrite_bitmap = (unsigned long *)__get_free_page(GFP_KERNEL);
+ if (!vmx_vmwrite_bitmap)
+ goto out6;
+
+ memset(vmx_vmread_bitmap, 0xff, PAGE_SIZE);
+ memset(vmx_vmwrite_bitmap, 0xff, PAGE_SIZE);
+ /* shadowed read/write fields */
+ for (i = 0; i < max_shadow_read_write_fields; i++) {
+ clear_bit(shadow_read_write_fields[i], vmx_vmwrite_bitmap);
+ clear_bit(shadow_read_write_fields[i], vmx_vmread_bitmap);
+ }
+ /* shadowed read only fields */
+ for (i = 0; i < max_shadow_read_only_fields; i++)
+ clear_bit(shadow_read_only_fields[i], vmx_vmread_bitmap);
/*
* Allow direct access to the PC debug port (it is often used for I/O
@@ -7959,7 +8041,7 @@ static int __init vmx_init(void)
r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx),
__alignof__(struct vcpu_vmx), THIS_MODULE);
if (r)
- goto out5;
+ goto out7;
#ifdef CONFIG_KEXEC
rcu_assign_pointer(crash_vmclear_loaded_vmcss,
@@ -8007,6 +8089,10 @@ static int __init vmx_init(void)
return 0;
+out7:
+ free_page((unsigned long)vmx_vmwrite_bitmap);
+out6:
+ free_page((unsigned long)vmx_vmread_bitmap);
out5:
free_page((unsigned long)vmx_msr_bitmap_longmode_x2apic);
out4:
@@ -8030,6 +8116,8 @@ static void __exit vmx_exit(void)
free_page((unsigned long)vmx_msr_bitmap_longmode);
free_page((unsigned long)vmx_io_bitmap_b);
free_page((unsigned long)vmx_io_bitmap_a);
+ free_page((unsigned long)vmx_vmwrite_bitmap);
+ free_page((unsigned long)vmx_vmread_bitmap);
#ifdef CONFIG_KEXEC
rcu_assign_pointer(crash_vmclear_loaded_vmcss, NULL);