diff options
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 64c42d90112..2c9661f230a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5062,6 +5062,30 @@ void kvm_after_handle_nmi(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL_GPL(kvm_after_handle_nmi); +static void kvm_set_mmio_spte_mask(void) +{ + u64 mask; + int maxphyaddr = boot_cpu_data.x86_phys_bits; + + /* + * Set the reserved bits and the present bit of an paging-structure + * entry to generate page fault with PFER.RSV = 1. + */ + mask = ((1ull << (62 - maxphyaddr + 1)) - 1) << maxphyaddr; + mask |= 1ull; + +#ifdef CONFIG_X86_64 + /* + * If reserved bit is not supported, clear the present bit to disable + * mmio page fault. + */ + if (maxphyaddr == 52) + mask &= ~1ull; +#endif + + kvm_mmu_set_mmio_spte_mask(mask); +} + int kvm_arch_init(void *opaque) { int r; @@ -5088,6 +5112,7 @@ int kvm_arch_init(void *opaque) if (r) goto out; + kvm_set_mmio_spte_mask(); kvm_init_msr_list(); kvm_x86_ops = ops; |