diff options
| author | Nadav Amit <namit@cs.technion.ac.il> | 2014-09-18 22:39:35 +0300 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2015-02-16 14:06:44 +0100 |
| commit | 293e0568a4320cec3d5226fbb3ed14abac3b05d1 (patch) | |
| tree | d535dd953e687efda9b73c2e68d25aa208253917 /arch | |
| parent | 297b900186075ead7d08bccb2d46137f1838b220 (diff) | |
KVM: x86: Warn if guest virtual address space is not 48-bits
commit dd598091de4aabbc8bd7290a04f364e443c03455 upstream.
The KVM emulator code assumes that the guest virtual address space (in 64-bit)
is 48-bits wide. Since we are about to add more code that makes the same
assumption, this patch adds an assertion to make sure guest virtual address
space is indeed 48-bits wide.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Bruce Rogers <brogers@suse.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 19 | ||||
| -rw-r--r-- | arch/x86/kvm/cpuid.h | 2 |
2 files changed, 13 insertions, 8 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index b110fe6c03d4..b132551528e5 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -23,14 +23,14 @@ #include "mmu.h" #include "trace.h" -void kvm_update_cpuid(struct kvm_vcpu *vcpu) +int kvm_update_cpuid(struct kvm_vcpu *vcpu) { struct kvm_cpuid_entry2 *best; struct kvm_lapic *apic = vcpu->arch.apic; best = kvm_find_cpuid_entry(vcpu, 1, 0); if (!best) - return; + return 0; /* Update OSXSAVE bit */ if (cpu_has_xsave && best->function == 0x1) { @@ -46,7 +46,15 @@ void kvm_update_cpuid(struct kvm_vcpu *vcpu) apic->lapic_timer.timer_mode_mask = 1 << 17; } + /* The existing code assumes virtual address is 48-bit in the canonical + * address checks; exit if it is ever changed */ + best = kvm_find_cpuid_entry(vcpu, 0x80000008, 0); + if (best && ((best->eax & 0xff00) >> 8) != 48 && + ((best->eax & 0xff00) >> 8) != 0) + return -EINVAL; + kvm_pmu_cpuid_update(vcpu); + return 0; } static int is_efer_nx(void) @@ -109,10 +117,9 @@ int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu, } vcpu->arch.cpuid_nent = cpuid->nent; cpuid_fix_nx_cap(vcpu); - r = 0; kvm_apic_set_version(vcpu); kvm_x86_ops->cpuid_update(vcpu); - kvm_update_cpuid(vcpu); + r = kvm_update_cpuid(vcpu); out_free: vfree(cpuid_entries); @@ -136,9 +143,7 @@ int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu, vcpu->arch.cpuid_nent = cpuid->nent; kvm_apic_set_version(vcpu); kvm_x86_ops->cpuid_update(vcpu); - kvm_update_cpuid(vcpu); - return 0; - + r = kvm_update_cpuid(vcpu); out: return r; } diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index b7fd07984888..6c458e37defb 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -3,7 +3,7 @@ #include "x86.h" -void kvm_update_cpuid(struct kvm_vcpu *vcpu); +int kvm_update_cpuid(struct kvm_vcpu *vcpu); struct kvm_cpuid_entry2 *kvm_find_cpuid_entry(struct kvm_vcpu *vcpu, u32 function, u32 index); int kvm_dev_ioctl_get_supported_cpuid(struct kvm_cpuid2 *cpuid, |