From 24c82e576b7860a4f02a21103e9df39e11e97006 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Wed, 18 May 2011 05:56:07 -0400 Subject: [PATCH] KVM: Sanitize cpuid Instead of blacklisting known-unsupported cpuid leaves, whitelist known- supported leaves. This is more conservative and prevents us from reporting features we don't support. Also whitelist a few more leaves while at it. Signed-off-by: Avi Kivity Acked-by: Joerg Roedel Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/x86.c | 37 +++++++++++++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0b089860e950..da48622d170f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2283,6 +2283,13 @@ static void do_cpuid_1_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->flags = 0; } +static bool supported_xcr0_bit(unsigned bit) +{ + u64 mask = ((u64)1 << bit); + + return mask & (XSTATE_FP | XSTATE_SSE | XSTATE_YMM) & host_xcr0; +} + #define F(x) bit(X86_FEATURE_##x) static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, @@ -2393,6 +2400,8 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, } break; } + case 9: + break; case 0xb: { int i, level_type; @@ -2414,7 +2423,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX; for (i = 1; *nent < maxnent && i < 64; ++i) { - if (entry[i].eax == 0) + if (entry[i].eax == 0 || !supported_xcr0_bit(i)) continue; do_cpuid_1_ent(&entry[i], function, i); entry[i].flags |= @@ -2451,6 +2460,24 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->ecx &= kvm_supported_word6_x86_features; cpuid_mask(&entry->ecx, 6); break; + case 0x80000008: { + unsigned g_phys_as = (entry->eax >> 16) & 0xff; + unsigned virt_as = max((entry->eax >> 8) & 0xff, 48U); + unsigned phys_as = entry->eax & 0xff; + + if (!g_phys_as) + g_phys_as = phys_as; + entry->eax = g_phys_as | (virt_as << 8); + entry->ebx = entry->edx = 0; + break; + } + case 0x80000019: + entry->ecx = entry->edx = 0; + break; + case 0x8000001a: + break; + case 0x8000001d: + break; /*Add support for Centaur's CPUID instruction*/ case 0xC0000000: /*Just support up to 0xC0000004 now*/ @@ -2460,10 +2487,16 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, entry->edx &= kvm_supported_word5_x86_features; cpuid_mask(&entry->edx, 5); break; + case 3: /* Processor serial number */ + case 5: /* MONITOR/MWAIT */ + case 6: /* Thermal management */ + case 0xA: /* Architectural Performance Monitoring */ + case 0x80000007: /* Advanced power management */ case 0xC0000002: case 0xC0000003: case 0xC0000004: - /*Now nothing to do, reserved for the future*/ + default: + entry->eax = entry->ebx = entry->ecx = entry->edx = 0; break; } -- 2.20.1