x86/hvm: add support for pcommit instruction

Pass PCOMMIT CPU feature into HVM domain. Currently, we do not intercept
pcommit instruction for L1 guest, and allow L1 to intercept pcommit
instruction for L2 guest.

The specification of pcommit instruction can be found in
https://software.intel.com/sites/default/files/managed/0d/53/319433-022.pdf

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Wei Liu <wei.liu2@citrix.com> for tools bits

diff --git a/tools/libxc/xc_cpufeature.h b/tools/libxc/xc_cpufeature.h
index 5288ac6e9e096d17d91a2b5ca0d0fce6d2bb5974..ee536796832ae373500ed6aae2d744055003083b 100644 (file)
--- a/tools/libxc/xc_cpufeature.h
+++ b/tools/libxc/xc_cpufeature.h
@@ -140,6 +140,7 @@
 #define X86_FEATURE_RDSEED      18 /* RDSEED instruction */
 #define X86_FEATURE_ADX         19 /* ADCX, ADOX instructions */
 #define X86_FEATURE_SMAP        20 /* Supervisor Mode Access Protection */
+#define X86_FEATURE_PCOMMIT     22 /* PCOMMIT instruction */
 #define X86_FEATURE_CLFLUSHOPT  23 /* CLFLUSHOPT instruction */
 #define X86_FEATURE_CLWB        24 /* CLWB instruction */
 

diff --git a/tools/libxc/xc_cpuid_x86.c b/tools/libxc/xc_cpuid_x86.c
index fecfd6cde77877c6127965008ff535d9b9c92f67..c1425957b91fa8e12ee771ff086b0b01df5ee8e7 100644 (file)
--- a/tools/libxc/xc_cpuid_x86.c
+++ b/tools/libxc/xc_cpuid_x86.c
@@ -427,6 +427,7 @@ static void xc_cpuid_hvm_policy(xc_interface *xch,
                         bitmaskof(X86_FEATURE_ADX)  |
                         bitmaskof(X86_FEATURE_SMAP) |
                         bitmaskof(X86_FEATURE_FSGSBASE) |
+                        bitmaskof(X86_FEATURE_PCOMMIT) |
                         bitmaskof(X86_FEATURE_CLWB) |
                         bitmaskof(X86_FEATURE_CLFLUSHOPT));
         } else

diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 21470ecccbd06e8fc546801d7d0c95f4ad0e3226..787b7def9b910a7c91608e57b708cc7d5046533c 100644 (file)
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -4583,21 +4583,28 @@ void hvm_cpuid(unsigned int input, unsigned int *eax, unsigned int *ebx,
             *edx &= ~cpufeat_mask(X86_FEATURE_PSE36);
         break;
     case 0x7:
-        if ( (count == 0) && !cpu_has_smep )
-            *ebx &= ~cpufeat_mask(X86_FEATURE_SMEP);
+        if ( count == 0 )
+        {
+            if ( !cpu_has_smep )
+                *ebx &= ~cpufeat_mask(X86_FEATURE_SMEP);
+
+            if ( !cpu_has_smap )
+                *ebx &= ~cpufeat_mask(X86_FEATURE_SMAP);
 
-        if ( (count == 0) && !cpu_has_smap )
-            *ebx &= ~cpufeat_mask(X86_FEATURE_SMAP);
+            /* Don't expose MPX to hvm when VMX support is not available */
+            if ( !(vmx_vmexit_control & VM_EXIT_CLEAR_BNDCFGS) ||
+                 !(vmx_vmentry_control & VM_ENTRY_LOAD_BNDCFGS) )
+                *ebx &= ~cpufeat_mask(X86_FEATURE_MPX);
 
-        /* Don't expose MPX to hvm when VMX support is not available */
-        if ( (count == 0) &&
-             (!(vmx_vmexit_control & VM_EXIT_CLEAR_BNDCFGS) ||
-              !(vmx_vmentry_control & VM_ENTRY_LOAD_BNDCFGS)) )
-            *ebx &= ~cpufeat_mask(X86_FEATURE_MPX);
+            /* Don't expose INVPCID to non-hap hvm. */
+            if ( !hap_enabled(d) )
+                *ebx &= ~cpufeat_mask(X86_FEATURE_INVPCID);
+
+            /* Don't expose PCOMMIT to hvm when VMX support is not available */
+            if ( !cpu_has_vmx_pcommit )
+                *ebx &= ~cpufeat_mask(X86_FEATURE_PCOMMIT);
+        }
 
-        /* Don't expose INVPCID to non-hap hvm. */
-        if ( (count == 0) && !hap_enabled(d) )
-            *ebx &= ~cpufeat_mask(X86_FEATURE_INVPCID);
         break;
     case 0xb:
         /* Fix the x2APIC identifier. */

diff --git a/xen/arch/x86/hvm/vmx/vmcs.c b/xen/arch/x86/hvm/vmx/vmcs.c
index edd4c8d4520607319fce8b913f5cbd8339978079..5bc3c74deda2df08505294b58f0c016ce16dbb79 100644 (file)
--- a/xen/arch/x86/hvm/vmx/vmcs.c
+++ b/xen/arch/x86/hvm/vmx/vmcs.c
@@ -242,7 +242,8 @@ static int vmx_init_vmcs_config(void)
                SECONDARY_EXEC_ENABLE_INVPCID |
                SECONDARY_EXEC_ENABLE_VM_FUNCTIONS |
                SECONDARY_EXEC_ENABLE_VIRT_EXCEPTIONS |
-               SECONDARY_EXEC_XSAVES);
+               SECONDARY_EXEC_XSAVES |
+               SECONDARY_EXEC_PCOMMIT);
         rdmsrl(MSR_IA32_VMX_MISC, _vmx_misc_cap);
         if ( _vmx_misc_cap & VMX_MISC_VMWRITE_ALL )
             opt |= SECONDARY_EXEC_ENABLE_VMCS_SHADOWING;
@@ -1075,6 +1076,12 @@ static int construct_vmcs(struct vcpu *v)
         __vmwrite(PLE_WINDOW, ple_window);
     }
 
+    /*
+     * We do not intercept pcommit for L1 guest and allow L1 hypervisor to
+     * intercept pcommit for L2 guest (see nvmx_n2_vmexit_handler()).
+     */
+    v->arch.hvm_vmx.secondary_exec_control &= ~SECONDARY_EXEC_PCOMMIT;
+
     if ( cpu_has_vmx_secondary_exec_control )
         __vmwrite(SECONDARY_VM_EXEC_CONTROL,
                   v->arch.hvm_vmx.secondary_exec_control);

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 7917fb70a9a40d84074c3a3268a24f9b61a6b5ce..04dde83b85b33739a383d34949e92ac070c0c5cb 100644 (file)
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -3543,6 +3543,7 @@ void vmx_vmexit_handler(struct cpu_user_regs *regs)
     case EXIT_REASON_ACCESS_LDTR_OR_TR:
     case EXIT_REASON_VMX_PREEMPTION_TIMER_EXPIRED:
     case EXIT_REASON_INVPCID:
+    case EXIT_REASON_PCOMMIT:
     /* fall through */
     default:
     exit_and_crash:

diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c
index ea1052e96b8586a4f658bc8900ee70a8d48d0661..271ec70e96ded0588b84ed4e8ae47eb989b956d9 100644 (file)
--- a/xen/arch/x86/hvm/vmx/vvmx.c
+++ b/xen/arch/x86/hvm/vmx/vvmx.c
@@ -1950,6 +1950,8 @@ int nvmx_msr_read_intercept(unsigned int msr, u64 *msr_content)
                SECONDARY_EXEC_ENABLE_VPID |
                SECONDARY_EXEC_UNRESTRICTED_GUEST |
                SECONDARY_EXEC_ENABLE_EPT;
+        if ( cpu_has_vmx_pcommit )
+            data |= SECONDARY_EXEC_PCOMMIT;
         data = gen_vmx_msr(data, 0, host_data);
         break;
     case MSR_IA32_VMX_EXIT_CTLS:
@@ -2226,6 +2228,7 @@ int nvmx_n2_vmexit_handler(struct cpu_user_regs *regs,
     case EXIT_REASON_VMXON:
     case EXIT_REASON_INVEPT:
     case EXIT_REASON_XSETBV:
+    case EXIT_REASON_PCOMMIT:
         /* inject to L1 */
         nvcpu->nv_vmexit_pending = 1;
         break;

diff --git a/xen/include/asm-x86/cpufeature.h b/xen/include/asm-x86/cpufeature.h
index ef965146efcf7772b8abad85c0ab2163782624db..23f9fb206f003e8dee0922e0da25bd81dcad5969 100644 (file)
--- a/xen/include/asm-x86/cpufeature.h
+++ b/xen/include/asm-x86/cpufeature.h
@@ -162,6 +162,7 @@
 #define X86_FEATURE_RDSEED     (7*32+18) /* RDSEED instruction */
 #define X86_FEATURE_ADX                (7*32+19) /* ADCX, ADOX instructions */
 #define X86_FEATURE_SMAP       (7*32+20) /* Supervisor Mode Access Prevention */
+#define X86_FEATURE_PCOMMIT    (7*32+22) /* PCOMMIT instruction */
 
 /* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx), word 8 */
 #define X86_FEATURE_PKU        (8*32+ 3) /* Protection Keys for Userspace */

diff --git a/xen/include/asm-x86/hvm/vmx/vmcs.h b/xen/include/asm-x86/hvm/vmx/vmcs.h
index d1496b8ce44d0a1f38410e027b344e3600c3233b..a5e7aee7817f29ec0003cc444a2ebb5d6806c08b 100644 (file)
--- a/xen/include/asm-x86/hvm/vmx/vmcs.h
+++ b/xen/include/asm-x86/hvm/vmx/vmcs.h
@@ -236,6 +236,7 @@ extern u32 vmx_vmentry_control;
 #define SECONDARY_EXEC_ENABLE_PML               0x00020000
 #define SECONDARY_EXEC_ENABLE_VIRT_EXCEPTIONS   0x00040000
 #define SECONDARY_EXEC_XSAVES                   0x00100000
+#define SECONDARY_EXEC_PCOMMIT                  0x00200000
 extern u32 vmx_secondary_exec_control;
 
 #define VMX_EPT_EXEC_ONLY_SUPPORTED                         0x00000001
@@ -303,7 +304,8 @@ extern u64 vmx_ept_vpid_cap;
     (vmx_secondary_exec_control & SECONDARY_EXEC_ENABLE_PML)
 #define cpu_has_vmx_xsaves \
     (vmx_secondary_exec_control & SECONDARY_EXEC_XSAVES)
-
+#define cpu_has_vmx_pcommit \
+    (vmx_secondary_exec_control & SECONDARY_EXEC_PCOMMIT)
 #define VMCS_RID_TYPE_MASK              0x80000000
 
 /* GUEST_INTERRUPTIBILITY_INFO flags. */

diff --git a/xen/include/asm-x86/hvm/vmx/vmx.h b/xen/include/asm-x86/hvm/vmx/vmx.h
index 1719965462ba6897bbc09784b1c9f7ef92877fc9..14f3d32ca15a51bb23bcf93e5fbc5264f8fbc16e 100644 (file)
--- a/xen/include/asm-x86/hvm/vmx/vmx.h
+++ b/xen/include/asm-x86/hvm/vmx/vmx.h
@@ -213,6 +213,7 @@ static inline void pi_clear_sn(struct pi_desc *pi_desc)
 #define EXIT_REASON_PML_FULL            62
 #define EXIT_REASON_XSAVES              63
 #define EXIT_REASON_XRSTORS             64
+#define EXIT_REASON_PCOMMIT             65
 
 /*
  * Interruption-information format