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Diffstat (limited to 'arch/x86/kvm/cpuid.c')
-rw-r--r--arch/x86/kvm/cpuid.c147
1 files changed, 130 insertions, 17 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index b110fe6c03d..38a0afe83c6 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -23,6 +23,36 @@
#include "mmu.h"
#include "trace.h"
+static u32 xstate_required_size(u64 xstate_bv)
+{
+ int feature_bit = 0;
+ u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
+
+ xstate_bv &= XSTATE_EXTEND_MASK;
+ while (xstate_bv) {
+ if (xstate_bv & 0x1) {
+ u32 eax, ebx, ecx, edx;
+ cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx);
+ ret = max(ret, eax + ebx);
+ }
+
+ xstate_bv >>= 1;
+ feature_bit++;
+ }
+
+ return ret;
+}
+
+u64 kvm_supported_xcr0(void)
+{
+ u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
+
+ if (!kvm_x86_ops->mpx_supported())
+ xcr0 &= ~(XSTATE_BNDREGS | XSTATE_BNDCSR);
+
+ return xcr0;
+}
+
void kvm_update_cpuid(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
@@ -46,6 +76,18 @@ void kvm_update_cpuid(struct kvm_vcpu *vcpu)
apic->lapic_timer.timer_mode_mask = 1 << 17;
}
+ best = kvm_find_cpuid_entry(vcpu, 0xD, 0);
+ if (!best) {
+ vcpu->arch.guest_supported_xcr0 = 0;
+ vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
+ } else {
+ vcpu->arch.guest_supported_xcr0 =
+ (best->eax | ((u64)best->edx << 32)) &
+ kvm_supported_xcr0();
+ vcpu->arch.guest_xstate_size = best->ebx =
+ xstate_required_size(vcpu->arch.xcr0);
+ }
+
kvm_pmu_cpuid_update(vcpu);
}
@@ -178,17 +220,32 @@ static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function,
entry->flags = 0;
}
-static bool supported_xcr0_bit(unsigned bit)
+#define F(x) bit(X86_FEATURE_##x)
+
+static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
+ u32 func, u32 index, int *nent, int maxnent)
{
- u64 mask = ((u64)1 << bit);
+ switch (func) {
+ case 0:
+ entry->eax = 1; /* only one leaf currently */
+ ++*nent;
+ break;
+ case 1:
+ entry->ecx = F(MOVBE);
+ ++*nent;
+ break;
+ default:
+ break;
+ }
- return mask & (XSTATE_FP | XSTATE_SSE | XSTATE_YMM) & host_xcr0;
-}
+ entry->function = func;
+ entry->index = index;
-#define F(x) bit(X86_FEATURE_##x)
+ return 0;
+}
-static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
- u32 index, int *nent, int maxnent)
+static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
+ u32 index, int *nent, int maxnent)
{
int r;
unsigned f_nx = is_efer_nx() ? F(NX) : 0;
@@ -202,6 +259,7 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
#endif
unsigned f_rdtscp = kvm_x86_ops->rdtscp_supported() ? F(RDTSCP) : 0;
unsigned f_invpcid = kvm_x86_ops->invpcid_supported() ? F(INVPCID) : 0;
+ unsigned f_mpx = kvm_x86_ops->mpx_supported() ? F(MPX) : 0;
/* cpuid 1.edx */
const u32 kvm_supported_word0_x86_features =
@@ -209,7 +267,7 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
F(TSC) | F(MSR) | F(PAE) | F(MCE) |
F(CX8) | F(APIC) | 0 /* Reserved */ | F(SEP) |
F(MTRR) | F(PGE) | F(MCA) | F(CMOV) |
- F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLSH) |
+ F(PAT) | F(PSE36) | 0 /* PSN */ | F(CLFLUSH) |
0 /* Reserved, DS, ACPI */ | F(MMX) |
F(FXSR) | F(XMM) | F(XMM2) | F(SELFSNOOP) |
0 /* HTT, TM, Reserved, PBE */;
@@ -225,6 +283,8 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
0 /* Reserved */ | f_lm | F(3DNOWEXT) | F(3DNOW);
/* cpuid 1.ecx */
const u32 kvm_supported_word4_x86_features =
+ /* NOTE: MONITOR (and MWAIT) are emulated as NOP,
+ * but *not* advertised to guests via CPUID ! */
F(XMM3) | F(PCLMULQDQ) | 0 /* DTES64, MONITOR */ |
0 /* DS-CPL, VMX, SMX, EST */ |
0 /* TM2 */ | F(SSSE3) | 0 /* CNXT-ID */ | 0 /* Reserved */ |
@@ -249,7 +309,8 @@ 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_invpcid | F(RTM);
+ F(BMI2) | F(ERMS) | f_invpcid | F(RTM) | f_mpx | F(RDSEED) |
+ F(ADX) | F(SMAP);
/* all calls to cpuid_count() should be made on the same cpu */
get_cpu();
@@ -382,14 +443,18 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
}
case 0xd: {
int idx, i;
+ u64 supported = kvm_supported_xcr0();
+ entry->eax &= supported;
+ entry->edx &= supported >> 32;
entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
for (idx = 1, i = 1; idx < 64; ++idx) {
+ u64 mask = ((u64)1 << idx);
if (*nent >= maxnent)
goto out;
do_cpuid_1_ent(&entry[i], function, idx);
- if (entry[i].eax == 0 || !supported_xcr0_bit(idx))
+ if (entry[i].eax == 0 || !(supported & mask))
continue;
entry[i].flags |=
KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
@@ -432,6 +497,13 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
entry->ecx &= kvm_supported_word6_x86_features;
cpuid_mask(&entry->ecx, 6);
break;
+ case 0x80000007: /* Advanced power management */
+ /* invariant TSC is CPUID.80000007H:EDX[8] */
+ entry->edx &= (1 << 8);
+ /* mask against host */
+ entry->edx &= boot_cpu_data.x86_power;
+ entry->eax = entry->ebx = entry->ecx = 0;
+ break;
case 0x80000008: {
unsigned g_phys_as = (entry->eax >> 16) & 0xff;
unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U);
@@ -462,7 +534,6 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
case 3: /* Processor serial number */
case 5: /* MONITOR/MWAIT */
case 6: /* Thermal management */
- case 0x80000007: /* Advanced power management */
case 0xC0000002:
case 0xC0000003:
case 0xC0000004:
@@ -481,6 +552,15 @@ out:
return r;
}
+static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func,
+ u32 idx, int *nent, int maxnent, unsigned int type)
+{
+ if (type == KVM_GET_EMULATED_CPUID)
+ return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);
+
+ return __do_cpuid_ent(entry, func, idx, nent, maxnent);
+}
+
#undef F
struct kvm_cpuid_param {
@@ -495,8 +575,36 @@ static bool is_centaur_cpu(const struct kvm_cpuid_param *param)
return boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR;
}
-int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid,
- struct kvm_cpuid_entry2 __user *entries)
+static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
+ __u32 num_entries, unsigned int ioctl_type)
+{
+ int i;
+ __u32 pad[3];
+
+ if (ioctl_type != KVM_GET_EMULATED_CPUID)
+ return false;
+
+ /*
+ * We want to make sure that ->padding is being passed clean from
+ * userspace in case we want to use it for something in the future.
+ *
+ * Sadly, this wasn't enforced for KVM_GET_SUPPORTED_CPUID and so we
+ * have to give ourselves satisfied only with the emulated side. /me
+ * sheds a tear.
+ */
+ for (i = 0; i < num_entries; i++) {
+ if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
+ return true;
+
+ if (pad[0] || pad[1] || pad[2])
+ return true;
+ }
+ return false;
+}
+
+int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,
+ struct kvm_cpuid_entry2 __user *entries,
+ unsigned int type)
{
struct kvm_cpuid_entry2 *cpuid_entries;
int limit, nent = 0, r = -E2BIG, i;
@@ -513,8 +621,12 @@ int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid,
goto out;
if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
cpuid->nent = KVM_MAX_CPUID_ENTRIES;
+
+ if (sanity_check_entries(entries, cpuid->nent, type))
+ return -EINVAL;
+
r = -ENOMEM;
- cpuid_entries = vmalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
+ cpuid_entries = vzalloc(sizeof(struct kvm_cpuid_entry2) * cpuid->nent);
if (!cpuid_entries)
goto out;
@@ -526,7 +638,7 @@ int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid,
continue;
r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx,
- &nent, cpuid->nent);
+ &nent, cpuid->nent, type);
if (r)
goto out_free;
@@ -537,7 +649,7 @@ int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid,
limit = cpuid_entries[nent - 1].eax;
for (func = ent->func + 1; func <= limit && nent < cpuid->nent && r == 0; ++func)
r = do_cpuid_ent(&cpuid_entries[nent], func, ent->idx,
- &nent, cpuid->nent);
+ &nent, cpuid->nent, type);
if (r)
goto out_free;
@@ -622,6 +734,7 @@ int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)
not_found:
return 36;
}
+EXPORT_SYMBOL_GPL(cpuid_maxphyaddr);
/*
* If no match is found, check whether we exceed the vCPU's limit
@@ -661,6 +774,7 @@ void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
*edx = best->edx;
} else
*eax = *ebx = *ecx = *edx = 0;
+ trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx);
}
EXPORT_SYMBOL_GPL(kvm_cpuid);
@@ -676,6 +790,5 @@ void kvm_emulate_cpuid(struct kvm_vcpu *vcpu)
kvm_register_write(vcpu, VCPU_REGS_RCX, ecx);
kvm_register_write(vcpu, VCPU_REGS_RDX, edx);
kvm_x86_ops->skip_emulated_instruction(vcpu);
- trace_kvm_cpuid(function, eax, ebx, ecx, edx);
}
EXPORT_SYMBOL_GPL(kvm_emulate_cpuid);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-03 23:10:25 +0000