[v3,1/5] Add CET xsaves/xrstors related macros and structures.

Commit Message

Yang, Weijiang Feb. 25, 2019, 1:37 p.m. UTC

CET protection in user mode and kernel mode relies on
specific MSRs, these MSRs' contents are automatically
saved/restored by xsaves/xrstors instructions.

Signed-off-by: Zhang Yi <[e-mail]>
Signed-off-by: Yang Weijiang <[e-mail]>
---
 target/i386/cpu.h | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

Comments

Paolo Bonzini March 8, 2019, 11:31 a.m. UTC | #1

On 25/02/19 14:37, Yang Weijiang wrote:
> +
>  typedef struct X86XSaveArea {
>      X86LegacyXSaveArea legacy;
>      X86XSaveHeader header;
> @@ -1039,6 +1070,9 @@ typedef struct X86XSaveArea {
>      XSaveHi16_ZMM hi16_zmm_state;
>      /* PKRU State: */
>      XSavePKRU pkru_state;
> +    /* CET State: */
> +    XSaveCETU cet_u;
> +    XSaveCETS cet_s;
>  } X86XSaveArea;
>  

Hi,

CET state should be retrieved or set not via XSAVE, but rather with
KVM_GET/SET_MSR, so this part is not needed.

Paolo

Patch

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 9c52d0cbeb..f3f724d8e6 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -469,6 +469,9 @@  typedef enum X86Seg {
 #define XSTATE_ZMM_Hi256_BIT            6
 #define XSTATE_Hi16_ZMM_BIT             7
 #define XSTATE_PKRU_BIT                 9
+#define XSTATE_RESERVED_BIT             10
+#define XSTATE_CET_U_BIT                11
+#define XSTATE_CET_S_BIT                12
 
 #define XSTATE_FP_MASK                  (1ULL << XSTATE_FP_BIT)
 #define XSTATE_SSE_MASK                 (1ULL << XSTATE_SSE_BIT)
@@ -479,6 +482,19 @@  typedef enum X86Seg {
 #define XSTATE_ZMM_Hi256_MASK           (1ULL << XSTATE_ZMM_Hi256_BIT)
 #define XSTATE_Hi16_ZMM_MASK            (1ULL << XSTATE_Hi16_ZMM_BIT)
 #define XSTATE_PKRU_MASK                (1ULL << XSTATE_PKRU_BIT)
+#define XSTATE_RESERVED_MASK            (1ULL << XSTATE_RESERVED_BIT)
+#define XSTATE_CET_U_MASK               (1ULL << XSTATE_CET_U_BIT)
+#define XSTATE_CET_S_MASK               (1ULL << XSTATE_CET_S_BIT)
+
+/* CPUID feature bits available in XCR0 */
+#define CPUID_XSTATE_USER_MASK  (XSTATE_FP_MASK | XSTATE_SSE_MASK \
+                                | XSTATE_YMM_MASK | XSTATE_BNDREGS_MASK \
+                                | XSTATE_BNDCSR_MASK | XSTATE_OPMASK_MASK \
+                                | XSTATE_ZMM_Hi256_MASK \
+                                | XSTATE_Hi16_ZMM_MASK | XSTATE_PKRU_MASK)
+
+/* CPUID feature bits available in XSS */
+#define CPUID_XSTATE_KERNEL_MASK    (XSTATE_CET_U_MASK | XSTATE_CET_S_MASK)
 
 /* CPUID feature words */
 typedef enum FeatureWord {
@@ -503,6 +519,8 @@  typedef enum FeatureWord {
     FEAT_XSAVE_COMP_LO, /* CPUID[EAX=0xd,ECX=0].EAX */
     FEAT_XSAVE_COMP_HI, /* CPUID[EAX=0xd,ECX=0].EDX */
     FEAT_ARCH_CAPABILITIES,
+    FEAT_XSAVE_SV_LO,   /* CPUID[EAX=0xd,ECX=1].ECX */
+    FEAT_XSAVE_SV_HI,   /* CPUID[EAX=0xd,ECX=1].EDX */
     FEATURE_WORDS,
 } FeatureWord;
 
@@ -687,7 +705,7 @@  typedef uint32_t FeatureWordArray[FEATURE_WORDS];
 #define CPUID_7_0_ECX_LA57     (1U << 16)
 #define CPUID_7_0_ECX_RDPID    (1U << 22)
 #define CPUID_7_0_ECX_CLDEMOTE (1U << 25)  /* CLDEMOTE Instruction */
-
+#define CPUID_7_0_ECX_CET_SHSTK     (1U << 7)  /* CET SHSTK feature bit */
 #define CPUID_7_0_EDX_AVX512_4VNNIW (1U << 2) /* AVX512 Neural Network Instructions */
 #define CPUID_7_0_EDX_AVX512_4FMAPS (1U << 3) /* AVX512 Multiply Accumulation Single Precision */
 #define CPUID_7_0_EDX_PCONFIG (1U << 18)       /* Platform Configuration */
@@ -1021,6 +1039,19 @@  typedef struct XSavePKRU {
     uint32_t padding;
 } XSavePKRU;
 
+/* Ext. save area 11: User mode CET state */
+typedef struct XSaveCETU {
+    uint64_t u_cet;
+    uint64_t user_ssp;
+} XSaveCETU;
+
+/* Ext. save area 12: Supervisor mode CET state */
+typedef struct XSaveCETS {
+    uint64_t kernel_ssp;
+    uint64_t pl1_ssp;
+    uint64_t pl2_ssp;
+} XSaveCETS;
+
 typedef struct X86XSaveArea {
     X86LegacyXSaveArea legacy;
     X86XSaveHeader header;
@@ -1039,6 +1070,9 @@  typedef struct X86XSaveArea {
     XSaveHi16_ZMM hi16_zmm_state;
     /* PKRU State: */
     XSavePKRU pkru_state;
+    /* CET State: */
+    XSaveCETU cet_u;
+    XSaveCETS cet_s;
 } X86XSaveArea;
 
 QEMU_BUILD_BUG_ON(offsetof(X86XSaveArea, avx_state) != 0x240);