[PATCH v6 2/9] vmx: spp: Add control flags for Sub-Page Protection(SPP)
From: Yang Weijiang
Date: Wed Nov 06 2019 - 02:42:56 EST
Check SPP capability in MSR_IA32_VMX_PROCBASED_CTLS2, its 23-bit
indicates SPP capability. Enable SPP feature bit in CPU capabilities
bitmap if it's supported.
Co-developed-by: He Chen <he.chen@xxxxxxxxxxxxxxx>
Signed-off-by: He Chen <he.chen@xxxxxxxxxxxxxxx>
Co-developed-by: Zhang Yi <yi.z.zhang@xxxxxxxxxxxxxxx>
Signed-off-by: Zhang Yi <yi.z.zhang@xxxxxxxxxxxxxxx>
Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx>
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/include/asm/vmx.h | 1 +
arch/x86/kernel/cpu/intel.c | 4 ++++
arch/x86/kvm/mmu.h | 2 ++
arch/x86/kvm/vmx/capabilities.h | 5 +++++
arch/x86/kvm/vmx/vmx.c | 9 +++++++++
6 files changed, 22 insertions(+)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index e880f2408e29..ee2c76fdadf6 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -228,6 +228,7 @@
#define X86_FEATURE_FLEXPRIORITY ( 8*32+ 2) /* Intel FlexPriority */
#define X86_FEATURE_EPT ( 8*32+ 3) /* Intel Extended Page Table */
#define X86_FEATURE_VPID ( 8*32+ 4) /* Intel Virtual Processor ID */
+#define X86_FEATURE_SPP ( 8*32+ 5) /* Intel EPT-based Sub-Page Write Protection */
#define X86_FEATURE_VMMCALL ( 8*32+15) /* Prefer VMMCALL to VMCALL */
#define X86_FEATURE_XENPV ( 8*32+16) /* "" Xen paravirtual guest */
diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index a39136b0d509..e1137807affc 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -68,6 +68,7 @@
#define SECONDARY_EXEC_XSAVES 0x00100000
#define SECONDARY_EXEC_PT_USE_GPA 0x01000000
#define SECONDARY_EXEC_MODE_BASED_EPT_EXEC 0x00400000
+#define SECONDARY_EXEC_ENABLE_SPP 0x00800000
#define SECONDARY_EXEC_TSC_SCALING 0x02000000
#define PIN_BASED_EXT_INTR_MASK 0x00000001
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 8d6d92ebeb54..27617e522f01 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -503,6 +503,7 @@ static void detect_vmx_virtcap(struct cpuinfo_x86 *c)
#define X86_VMX_FEATURE_PROC_CTLS2_EPT 0x00000002
#define X86_VMX_FEATURE_PROC_CTLS2_VPID 0x00000020
#define x86_VMX_FEATURE_EPT_CAP_AD 0x00200000
+#define X86_VMX_FEATURE_PROC_CTLS2_SPP 0x00800000
u32 vmx_msr_low, vmx_msr_high, msr_ctl, msr_ctl2;
u32 msr_vpid_cap, msr_ept_cap;
@@ -513,6 +514,7 @@ static void detect_vmx_virtcap(struct cpuinfo_x86 *c)
clear_cpu_cap(c, X86_FEATURE_EPT);
clear_cpu_cap(c, X86_FEATURE_VPID);
clear_cpu_cap(c, X86_FEATURE_EPT_AD);
+ clear_cpu_cap(c, X86_FEATURE_SPP);
rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, vmx_msr_low, vmx_msr_high);
msr_ctl = vmx_msr_high | vmx_msr_low;
@@ -536,6 +538,8 @@ static void detect_vmx_virtcap(struct cpuinfo_x86 *c)
}
if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VPID)
set_cpu_cap(c, X86_FEATURE_VPID);
+ if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_SPP)
+ set_cpu_cap(c, X86_FEATURE_SPP);
}
}
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 54c2a377795b..3c1423526a98 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -26,6 +26,8 @@
#define PT_PAGE_SIZE_MASK (1ULL << PT_PAGE_SIZE_SHIFT)
#define PT_PAT_MASK (1ULL << 7)
#define PT_GLOBAL_MASK (1ULL << 8)
+#define PT_SPP_SHIFT 61
+#define PT_SPP_MASK (1ULL << PT_SPP_SHIFT)
#define PT64_NX_SHIFT 63
#define PT64_NX_MASK (1ULL << PT64_NX_SHIFT)
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index d6664ee3d127..e3bde7a32123 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -241,6 +241,11 @@ static inline bool cpu_has_vmx_pml(void)
return vmcs_config.cpu_based_2nd_exec_ctrl & SECONDARY_EXEC_ENABLE_PML;
}
+static inline bool cpu_has_vmx_ept_spp(void)
+{
+ return vmcs_config.cpu_based_2nd_exec_ctrl & SECONDARY_EXEC_ENABLE_SPP;
+}
+
static inline bool vmx_xsaves_supported(void)
{
return vmcs_config.cpu_based_2nd_exec_ctrl &
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index c030c96fc81a..0fcd02b531ef 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -60,6 +60,7 @@
#include "vmcs12.h"
#include "vmx.h"
#include "x86.h"
+#include "spp.h"
MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");
@@ -113,6 +114,7 @@ module_param_named(pml, enable_pml, bool, S_IRUGO);
static bool __read_mostly dump_invalid_vmcs = 0;
module_param(dump_invalid_vmcs, bool, 0644);
+static bool __read_mostly spp_supported = 0;
#define MSR_BITMAP_MODE_X2APIC 1
#define MSR_BITMAP_MODE_X2APIC_APICV 2
@@ -2279,6 +2281,7 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
SECONDARY_EXEC_RDSEED_EXITING |
SECONDARY_EXEC_RDRAND_EXITING |
SECONDARY_EXEC_ENABLE_PML |
+ SECONDARY_EXEC_ENABLE_SPP |
SECONDARY_EXEC_TSC_SCALING |
SECONDARY_EXEC_PT_USE_GPA |
SECONDARY_EXEC_PT_CONCEAL_VMX |
@@ -3931,6 +3934,9 @@ static void vmx_compute_secondary_exec_control(struct vcpu_vmx *vmx)
if (!enable_pml)
exec_control &= ~SECONDARY_EXEC_ENABLE_PML;
+ if (!spp_supported)
+ exec_control &= ~SECONDARY_EXEC_ENABLE_SPP;
+
if (vmx_xsaves_supported()) {
/* Exposing XSAVES only when XSAVE is exposed */
bool xsaves_enabled =
@@ -7521,6 +7527,9 @@ static __init int hardware_setup(void)
if (!cpu_has_vmx_flexpriority())
flexpriority_enabled = 0;
+ if (cpu_has_vmx_ept_spp() && enable_ept)
+ spp_supported = 1;
+
if (!cpu_has_virtual_nmis())
enable_vnmi = 0;
--
2.17.2