From ad756a1603c5fac207758faaac7f01c34c9d0b7b Mon Sep 17 00:00:00 2001 From: "Mao, Junjie" Date: Mon, 2 Jul 2012 01:18:48 +0000 Subject: [PATCH] KVM: VMX: Implement PCID/INVPCID for guests with EPT This patch handles PCID/INVPCID for guests. Process-context identifiers (PCIDs) are a facility by which a logical processor may cache information for multiple linear-address spaces so that the processor may retain cached information when software switches to a different linear address space. Refer to section 4.10.1 in IA32 Intel Software Developer's Manual Volume 3A for details. For guests with EPT, the PCID feature is enabled and INVPCID behaves as running natively. For guests without EPT, the PCID feature is disabled and INVPCID triggers #UD. Signed-off-by: Junjie Mao Signed-off-by: Avi Kivity --- arch/x86/include/asm/kvm_host.h | 4 ++- arch/x86/include/asm/processor-flags.h | 2 ++ arch/x86/include/asm/vmx.h | 2 ++ arch/x86/kvm/cpuid.c | 5 ++-- arch/x86/kvm/cpuid.h | 8 ++++++ arch/x86/kvm/svm.c | 6 +++++ arch/x86/kvm/vmx.c | 34 +++++++++++++++++++++++++- arch/x86/kvm/x86.c | 23 ++++++++++++++--- 8 files changed, 77 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 24b76474d9de..a3e9409e90b6 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -48,12 +48,13 @@ #define CR3_PAE_RESERVED_BITS ((X86_CR3_PWT | X86_CR3_PCD) - 1) #define CR3_NONPAE_RESERVED_BITS ((PAGE_SIZE-1) & ~(X86_CR3_PWT | X86_CR3_PCD)) +#define CR3_PCID_ENABLED_RESERVED_BITS 0xFFFFFF0000000000ULL #define CR3_L_MODE_RESERVED_BITS (CR3_NONPAE_RESERVED_BITS | \ 0xFFFFFF0000000000ULL) #define CR4_RESERVED_BITS \ (~(unsigned long)(X86_CR4_VME | X86_CR4_PVI | X86_CR4_TSD | X86_CR4_DE\ | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_MCE \ - | X86_CR4_PGE | X86_CR4_PCE | X86_CR4_OSFXSR \ + | X86_CR4_PGE | X86_CR4_PCE | X86_CR4_OSFXSR | X86_CR4_PCIDE \ | X86_CR4_OSXSAVE | X86_CR4_SMEP | X86_CR4_RDWRGSFS \ | X86_CR4_OSXMMEXCPT | X86_CR4_VMXE)) @@ -673,6 +674,7 @@ struct kvm_x86_ops { u64 (*get_mt_mask)(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio); int (*get_lpage_level)(void); bool (*rdtscp_supported)(void); + bool (*invpcid_supported)(void); void (*adjust_tsc_offset)(struct kvm_vcpu *vcpu, s64 adjustment, bool host); void (*set_tdp_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3); diff --git a/arch/x86/include/asm/processor-flags.h b/arch/x86/include/asm/processor-flags.h index f8ab3eaad128..aea1d1d848c7 100644 --- a/arch/x86/include/asm/processor-flags.h +++ b/arch/x86/include/asm/processor-flags.h @@ -44,6 +44,7 @@ */ #define X86_CR3_PWT 0x00000008 /* Page Write Through */ #define X86_CR3_PCD 0x00000010 /* Page Cache Disable */ +#define X86_CR3_PCID_MASK 0x00000fff /* PCID Mask */ /* * Intel CPU features in CR4 @@ -61,6 +62,7 @@ #define X86_CR4_OSXMMEXCPT 0x00000400 /* enable unmasked SSE exceptions */ #define X86_CR4_VMXE 0x00002000 /* enable VMX virtualization */ #define X86_CR4_RDWRGSFS 0x00010000 /* enable RDWRGSFS support */ +#define X86_CR4_PCIDE 0x00020000 /* enable PCID support */ #define X86_CR4_OSXSAVE 0x00040000 /* enable xsave and xrestore */ #define X86_CR4_SMEP 0x00100000 /* enable SMEP support */ diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h index de007c272730..74fcb963595b 100644 --- a/arch/x86/include/asm/vmx.h +++ b/arch/x86/include/asm/vmx.h @@ -60,6 +60,7 @@ #define SECONDARY_EXEC_WBINVD_EXITING 0x00000040 #define SECONDARY_EXEC_UNRESTRICTED_GUEST 0x00000080 #define SECONDARY_EXEC_PAUSE_LOOP_EXITING 0x00000400 +#define SECONDARY_EXEC_ENABLE_INVPCID 0x00001000 #define PIN_BASED_EXT_INTR_MASK 0x00000001 @@ -281,6 +282,7 @@ enum vmcs_field { #define EXIT_REASON_EPT_MISCONFIG 49 #define EXIT_REASON_WBINVD 54 #define EXIT_REASON_XSETBV 55 +#define EXIT_REASON_INVPCID 58 /* * Interruption-information format diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 197afd53e3a4..0595f1397b7c 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -201,6 +201,7 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, unsigned f_lm = 0; #endif unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0; + unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0; /* cpuid 1.edx */ const u32 kvm_supported_word0_x86_features = @@ -228,7 +229,7 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, 0 /* DS-CPL, VMX, SMX, EST */ | 0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ | F(FMA) | F(CX16) | 0 /* xTPR Update, PDCM */ | - 0 /* Reserved, DCA */ | F(XMM4_1) | + F(PCID) | 0 /* Reserved, DCA */ | F(XMM4_1) | F(XMM4_2) | F(X2APIC) | F(MOVBE) | F(POPCNT) | 0 /* Reserved*/ | F(AES) | F(XSAVE) | 0 /* OSXSAVE */ | F(AVX) | F(F16C) | F(RDRAND); @@ -248,7 +249,7 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, /* cpuid 7.0.ebx */ const u32 kvm_supported_word9_x86_features = F(FSGSBASE) | F(BMI1) | F(HLE) | F(AVX2) | F(SMEP) | - F(BMI2) | F(ERMS) | F(RTM); + F(BMI2) | F(ERMS) | f_invpcid | F(RTM); /* all calls to cpuid_count() should be made on the same cpu */ get_cpu(); diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index f449edc35e24..a10e46016851 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -52,4 +52,12 @@ static inline bool guest_cpuid_has_osvw(struct kvm_vcpu *vcpu) return best && (best->ecx & bit(X86_FEATURE_OSVW)); } +static inline bool guest_cpuid_has_pcid(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 1, 0); + return best && (best->ecx & bit(X86_FEATURE_PCID)); +} + #endif diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 7a418783259d..baead950d6c8 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -4044,6 +4044,11 @@ static bool svm_rdtscp_supported(void) return false; } +static bool svm_invpcid_supported(void) +{ + return false; +} + static bool svm_has_wbinvd_exit(void) { return true; @@ -4312,6 +4317,7 @@ static struct kvm_x86_ops svm_x86_ops = { .cpuid_update = svm_cpuid_update, .rdtscp_supported = svm_rdtscp_supported, + .invpcid_supported = svm_invpcid_supported, .set_supported_cpuid = svm_set_supported_cpuid, diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 5c52a6d29908..c39b60707e02 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -861,6 +861,12 @@ static inline bool cpu_has_vmx_rdtscp(void) SECONDARY_EXEC_RDTSCP; } +static inline bool cpu_has_vmx_invpcid(void) +{ + return vmcs_config.cpu_based_2nd_exec_ctrl & + SECONDARY_EXEC_ENABLE_INVPCID; +} + static inline bool cpu_has_virtual_nmis(void) { return vmcs_config.pin_based_exec_ctrl & PIN_BASED_VIRTUAL_NMIS; @@ -1751,6 +1757,11 @@ static bool vmx_rdtscp_supported(void) return cpu_has_vmx_rdtscp(); } +static bool vmx_invpcid_supported(void) +{ + return cpu_has_vmx_invpcid() && enable_ept; +} + /* * Swap MSR entry in host/guest MSR entry array. */ @@ -2470,7 +2481,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf) SECONDARY_EXEC_ENABLE_EPT | SECONDARY_EXEC_UNRESTRICTED_GUEST | SECONDARY_EXEC_PAUSE_LOOP_EXITING | - SECONDARY_EXEC_RDTSCP; + SECONDARY_EXEC_RDTSCP | + SECONDARY_EXEC_ENABLE_INVPCID; if (adjust_vmx_controls(min2, opt2, MSR_IA32_VMX_PROCBASED_CTLS2, &_cpu_based_2nd_exec_control) < 0) @@ -3800,6 +3812,8 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx) if (!enable_ept) { exec_control &= ~SECONDARY_EXEC_ENABLE_EPT; enable_unrestricted_guest = 0; + /* Enable INVPCID for non-ept guests may cause performance regression. */ + exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID; } if (!enable_unrestricted_guest) exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST; @@ -6550,6 +6564,23 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu) } } } + + exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL); + /* Exposing INVPCID only when PCID is exposed */ + best = kvm_find_cpuid_entry(vcpu, 0x7, 0); + if (vmx_invpcid_supported() && + best && (best->ecx & bit(X86_FEATURE_INVPCID)) && + guest_cpuid_has_pcid(vcpu)) { + exec_control |= SECONDARY_EXEC_ENABLE_INVPCID; + vmcs_write32(SECONDARY_VM_EXEC_CONTROL, + exec_control); + } else { + exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID; + vmcs_write32(SECONDARY_VM_EXEC_CONTROL, + exec_control); + if (best) + best->ecx &= ~bit(X86_FEATURE_INVPCID); + } } static void vmx_set_supported_cpuid(u32 func, struct kvm_cpuid_entry2 *entry) @@ -7284,6 +7315,7 @@ static struct kvm_x86_ops vmx_x86_ops = { .cpuid_update = vmx_cpuid_update, .rdtscp_supported = vmx_rdtscp_supported, + .invpcid_supported = vmx_invpcid_supported, .set_supported_cpuid = vmx_set_supported_cpuid, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ff0b487e7254..59b59508ff07 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -528,6 +528,9 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) return 1; } + if (!(cr0 & X86_CR0_PG) && kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE)) + return 1; + kvm_x86_ops->set_cr0(vcpu, cr0); if ((cr0 ^ old_cr0) & X86_CR0_PG) { @@ -604,10 +607,20 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) kvm_read_cr3(vcpu))) return 1; + if ((cr4 & X86_CR4_PCIDE) && !(old_cr4 & X86_CR4_PCIDE)) { + if (!guest_cpuid_has_pcid(vcpu)) + return 1; + + /* PCID can not be enabled when cr3[11:0]!=000H or EFER.LMA=0 */ + if ((kvm_read_cr3(vcpu) & X86_CR3_PCID_MASK) || !is_long_mode(vcpu)) + return 1; + } + if (kvm_x86_ops->set_cr4(vcpu, cr4)) return 1; - if ((cr4 ^ old_cr4) & pdptr_bits) + if (((cr4 ^ old_cr4) & pdptr_bits) || + (!(cr4 & X86_CR4_PCIDE) && (old_cr4 & X86_CR4_PCIDE))) kvm_mmu_reset_context(vcpu); if ((cr4 ^ old_cr4) & X86_CR4_OSXSAVE) @@ -626,8 +639,12 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) } if (is_long_mode(vcpu)) { - if (cr3 & CR3_L_MODE_RESERVED_BITS) - return 1; + if (kvm_read_cr4(vcpu) & X86_CR4_PCIDE) { + if (cr3 & CR3_PCID_ENABLED_RESERVED_BITS) + return 1; + } else + if (cr3 & CR3_L_MODE_RESERVED_BITS) + return 1; } else { if (is_pae(vcpu)) { if (cr3 & CR3_PAE_RESERVED_BITS) -- 2.34.1