-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 the uppermost physical address bit, which would be reserved as
- * long as the supported physical address width is less than 52.
- */
- mask = 1ull << 51;
-
- /* Set the present bit. */
- mask |= 1ull;
-
- /*
- * If reserved bit is not supported, clear the present bit to disable
- * mmio page fault.
- */
- if (IS_ENABLED(CONFIG_X86_64) && maxphyaddr == 52)
- mask &= ~1ull;
-
- kvm_mmu_set_mmio_spte_mask(mask, mask);
-}
-