diff options
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/vmx.c | 90 |
1 files changed, 89 insertions, 1 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 7042b69..7dc5996 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); |