diff options
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 113 |
1 files changed, 63 insertions, 50 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 47be763e1b6..52593e8e1ae 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -183,9 +183,10 @@ static bool supported_xcr0_bit(unsigned bit) #define F(x) bit(X86_FEATURE_##x) -static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, +static 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; #ifdef CONFIG_X86_64 unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL) @@ -246,6 +247,12 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, /* all calls to cpuid_count() should be made on the same cpu */ get_cpu(); + + r = -E2BIG; + + if (*nent >= maxnent) + goto out; + do_cpuid_1_ent(entry, function, index); ++*nent; @@ -271,7 +278,10 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->flags |= KVM_CPUID_FLAG_STATEFUL_FUNC; entry->flags |= KVM_CPUID_FLAG_STATE_READ_NEXT; - for (t = 1; t < times && *nent < maxnent; ++t) { + for (t = 1; t < times; ++t) { + if (*nent >= maxnent) + goto out; + do_cpuid_1_ent(&entry[t], function, 0); entry[t].flags |= KVM_CPUID_FLAG_STATEFUL_FUNC; ++*nent; @@ -284,7 +294,10 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; /* read more entries until cache_type is zero */ - for (i = 1; *nent < maxnent; ++i) { + for (i = 1; ; ++i) { + if (*nent >= maxnent) + goto out; + cache_type = entry[i - 1].eax & 0x1f; if (!cache_type) break; @@ -316,7 +329,10 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; /* read more entries until level_type is zero */ - for (i = 1; *nent < maxnent; ++i) { + for (i = 1; ; ++i) { + if (*nent >= maxnent) + goto out; + level_type = entry[i - 1].ecx & 0xff00; if (!level_type) break; @@ -331,7 +347,10 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, int idx, i; entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; - for (idx = 1, i = 1; *nent < maxnent && idx < 64; ++idx) { + for (idx = 1, i = 1; idx < 64; ++idx) { + if (*nent >= maxnent) + goto out; + do_cpuid_1_ent(&entry[i], function, idx); if (entry[i].eax == 0 || !supported_xcr0_bit(idx)) continue; @@ -416,17 +435,41 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, kvm_x86_ops->set_supported_cpuid(function, entry); + r = 0; + +out: put_cpu(); + + return r; } #undef F +struct kvm_cpuid_param { + u32 func; + u32 idx; + bool has_leaf_count; + bool (*qualifier)(struct kvm_cpuid_param *param); +}; + +static bool is_centaur_cpu(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) { struct kvm_cpuid_entry2 *cpuid_entries; - int limit, nent = 0, r = -E2BIG; + int limit, nent = 0, r = -E2BIG, i; u32 func; + static struct kvm_cpuid_param param[] = { + { .func = 0, .has_leaf_count = true }, + { .func = 0x80000000, .has_leaf_count = true }, + { .func = 0xC0000000, .qualifier = is_centaur_cpu, .has_leaf_count = true }, + { .func = KVM_CPUID_SIGNATURE }, + { .func = KVM_CPUID_FEATURES }, + }; if (cpuid->nent < 1) goto out; @@ -437,61 +480,31 @@ int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid, if (!cpuid_entries) goto out; - do_cpuid_ent(&cpuid_entries[0], 0, 0, &nent, cpuid->nent); - limit = cpuid_entries[0].eax; - for (func = 1; func <= limit && nent < cpuid->nent; ++func) - do_cpuid_ent(&cpuid_entries[nent], func, 0, - &nent, cpuid->nent); - r = -E2BIG; - if (nent >= cpuid->nent) - goto out_free; - - do_cpuid_ent(&cpuid_entries[nent], 0x80000000, 0, &nent, cpuid->nent); - limit = cpuid_entries[nent - 1].eax; - for (func = 0x80000001; func <= limit && nent < cpuid->nent; ++func) - do_cpuid_ent(&cpuid_entries[nent], func, 0, - &nent, cpuid->nent); - - + r = 0; + for (i = 0; i < ARRAY_SIZE(param); i++) { + struct kvm_cpuid_param *ent = ¶m[i]; - r = -E2BIG; - if (nent >= cpuid->nent) - goto out_free; + if (ent->qualifier && !ent->qualifier(ent)) + continue; - /* Add support for Centaur's CPUID instruction. */ - if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR) { - do_cpuid_ent(&cpuid_entries[nent], 0xC0000000, 0, + r = do_cpuid_ent(&cpuid_entries[nent], ent->func, ent->idx, &nent, cpuid->nent); - r = -E2BIG; - if (nent >= cpuid->nent) + if (r) goto out_free; + if (!ent->has_leaf_count) + continue; + limit = cpuid_entries[nent - 1].eax; - for (func = 0xC0000001; - func <= limit && nent < cpuid->nent; ++func) - do_cpuid_ent(&cpuid_entries[nent], func, 0, - &nent, cpuid->nent); + 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); - r = -E2BIG; - if (nent >= cpuid->nent) + if (r) goto out_free; } - do_cpuid_ent(&cpuid_entries[nent], KVM_CPUID_SIGNATURE, 0, &nent, - cpuid->nent); - - r = -E2BIG; - if (nent >= cpuid->nent) - goto out_free; - - do_cpuid_ent(&cpuid_entries[nent], KVM_CPUID_FEATURES, 0, &nent, - cpuid->nent); - - r = -E2BIG; - if (nent >= cpuid->nent) - goto out_free; - r = -EFAULT; if (copy_to_user(entries, cpuid_entries, nent * sizeof(struct kvm_cpuid_entry2))) |