On 6/19/2019 9:21 AM, Liran Alon wrote:
Improve the KVM_{GET,SET}_NESTED_STATE structs by detailing the format
of VMX nested state data in a struct.
In order to avoid changing the ioctl values of
KVM_{GET,SET}_NESTED_STATE, there is a need to preserve
sizeof(struct kvm_nested_state). This is done by defining the data
struct as "data.vmx[0]". It was the most elegant way I found to
preserve struct size while still keeping struct readable and easy to
maintain. It does have a misfortunate side-effect that now it has to be
accessed as "data.vmx[0]" rather than just "data.vmx".
Because we are already modifying these structs, I also modified the
following:
* Define the "format" field values as macros.
* Rename vmcs_pa to vmcs12_pa for better readability.
Signed-off-by: Liran Alon <liran.alon@xxxxxxxxxx>
---
linux-headers/asm-x86/kvm.h | 33 ++++++++++++++++++++++-----------
1 file changed, 22 insertions(+), 11 deletions(-)
diff --git a/linux-headers/asm-x86/kvm.h b/linux-headers/asm-x86/kvm.h
index 7a0e64ccd6ff..6e7dd792e448 100644
--- a/linux-headers/asm-x86/kvm.h
+++ b/linux-headers/asm-x86/kvm.h
@@ -383,16 +383,26 @@ struct kvm_sync_regs {
#define KVM_X86_QUIRK_LAPIC_MMIO_HOLE (1 << 2)
#define KVM_X86_QUIRK_OUT_7E_INC_RIP (1 << 3)
+#define KVM_STATE_NESTED_FORMAT_VMX 0
+#define KVM_STATE_NESTED_FORMAT_SVM 1
+
#define KVM_STATE_NESTED_GUEST_MODE 0x00000001
#define KVM_STATE_NESTED_RUN_PENDING 0x00000002
#define KVM_STATE_NESTED_EVMCS 0x00000004
+#define KVM_STATE_NESTED_VMX_VMCS_SIZE 0x1000
+
#define KVM_STATE_NESTED_SMM_GUEST_MODE 0x00000001
#define KVM_STATE_NESTED_SMM_VMXON 0x00000002
-struct kvm_vmx_nested_state {
+struct kvm_vmx_nested_state_data {
+ __u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
+ __u8 shadow_vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
+};
+
+struct kvm_vmx_nested_state_hdr {
__u64 vmxon_pa;
- __u64 vmcs_pa;
+ __u64 vmcs12_pa;
struct {
__u16 flags;
@@ -401,24 +411,25 @@ struct kvm_vmx_nested_state {
/* for KVM_CAP_NESTED_STATE */
struct kvm_nested_state {
- /* KVM_STATE_* flags */
__u16 flags;
-
- /* 0 for VMX, 1 for SVM. */
__u16 format;
-
- /* 128 for SVM, 128 + VMCS size for VMX. */
__u32 size;
union {
- /* VMXON, VMCS */
- struct kvm_vmx_nested_state vmx;
+ struct kvm_vmx_nested_state_hdr vmx;
/* Pad the header to 128 bytes. */
__u8 pad[120];
- };
+ } hdr;
- __u8 data[0];
+ /*
+ * Define data region as 0 bytes to preserve backwards-compatability
+ * to old definition of kvm_nested_state in order to avoid changing
+ * KVM_{GET,PUT}_NESTED_STATE ioctl values.
+ */
+ union {
+ struct kvm_vmx_nested_state_data vmx[0];
+ } data;
};
#endif /* _ASM_X86_KVM_H */
Reviewed-by: Maran Wilson <maran.wilson@xxxxxxxxxx>
Thanks,
-Maran
