KVM: x86: silence preempt warning on kvm_write_guest_time

[karo-tx-linux.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7c1ce5ac61311d49b8af706d744f49d4a480999d..ee4714b9dbaee4c2fa93e454f5e79248db96cfe4 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -338,6 +338,9 @@ EXPORT_SYMBOL_GPL(kvm_lmsw);
 
 void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 {
+       unsigned long old_cr4 = vcpu->arch.cr4;
+       unsigned long pdptr_bits = X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE;
+
        if (cr4 & CR4_RESERVED_BITS) {
                printk(KERN_DEBUG "set_cr4: #GP, reserved bits\n");
                kvm_inject_gp(vcpu, 0);
@@ -351,7 +354,8 @@ void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
                        kvm_inject_gp(vcpu, 0);
                        return;
                }
-       } else if (is_paging(vcpu) && !is_pae(vcpu) && (cr4 & X86_CR4_PAE)
+       } else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE)
+                  && ((cr4 ^ old_cr4) & pdptr_bits)
                   && !load_pdptrs(vcpu, vcpu->arch.cr3)) {
                printk(KERN_DEBUG "set_cr4: #GP, pdptrs reserved bits\n");
                kvm_inject_gp(vcpu, 0);
@@ -630,10 +634,12 @@ static void kvm_write_guest_time(struct kvm_vcpu *v)
        if ((!vcpu->time_page))
                return;
 
+       preempt_disable();
        if (unlikely(vcpu->hv_clock_tsc_khz != __get_cpu_var(cpu_tsc_khz))) {
                kvm_set_time_scale(__get_cpu_var(cpu_tsc_khz), &vcpu->hv_clock);
                vcpu->hv_clock_tsc_khz = __get_cpu_var(cpu_tsc_khz);
        }
+       preempt_enable();
 
        /* Keep irq disabled to prevent changes to the clock */
        local_irq_save(flags);
@@ -1121,9 +1127,9 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 
 static int is_efer_nx(void)
 {
-       u64 efer;
+       unsigned long long efer = 0;
 
-       rdmsrl(MSR_EFER, efer);
+       rdmsrl_safe(MSR_EFER, &efer);
        return efer & EFER_NX;
 }
 
@@ -1259,7 +1265,7 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
                bit(X86_FEATURE_CMOV) | bit(X86_FEATURE_PSE36) |
                bit(X86_FEATURE_MMX) | bit(X86_FEATURE_FXSR) |
                bit(X86_FEATURE_SYSCALL) |
-               (bit(X86_FEATURE_NX) && is_efer_nx()) |
+               (is_efer_nx() ? bit(X86_FEATURE_NX) : 0) |
 #ifdef CONFIG_X86_64
                bit(X86_FEATURE_LM) |
 #endif
@@ -3930,7 +3936,13 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 
        vcpu->arch.cr2 = sregs->cr2;
        mmu_reset_needed |= vcpu->arch.cr3 != sregs->cr3;
-       vcpu->arch.cr3 = sregs->cr3;
+
+       down_read(&vcpu->kvm->slots_lock);
+       if (gfn_to_memslot(vcpu->kvm, sregs->cr3 >> PAGE_SHIFT))
+               vcpu->arch.cr3 = sregs->cr3;
+       else
+               set_bit(KVM_REQ_TRIPLE_FAULT, &vcpu->requests);
+       up_read(&vcpu->kvm->slots_lock);
 
        kvm_set_cr8(vcpu, sregs->cr8);