acpi: track vaddr of ACPI tables

Previously, the physical address of the ACPI tables were being
tracked. This caused a Linux error while parsing the ACPI tables. Since
Linux does not have access to those memory regions, they would appear
empty, causing an Invalid Table Length bug print. By tracking the
virtual address that Linux expects and placing the vaddr into the ACPI
tables, Linux can parse the tables properly.

libsel4vmmplatsupport/src/arch/x86/acpi.c

@@ -257,16 +257,19 @@ int make_guest_acpi_tables(vm_t *vm)
     }
 
     uintptr_t xsdt_addr = lower_bios_addr + (XSDT_START - LOWER_BIOS_START);
+    uintptr_t xsdt_vaddr = XSDT_START;
 
     acpi_xsdt_t *xsdt = calloc(1, xsdt_size);
     acpi_fill_table_head(&xsdt->header, "XSDT", 1);
 
     // Add previous tables to XSDT pointer list
     uintptr_t table_paddr = xsdt_addr + xsdt_size;
+    uintptr_t table_vaddr = xsdt_vaddr + xsdt_size;
     uint64_t *entry = (uint64_t *)((char *)xsdt + sizeof(acpi_xsdt_t));
     for (int i = 1; i < num_tables; i++) {
-        *entry++ = (uint64_t)table_paddr;
+        *entry++ = (uint64_t)table_vaddr;
         table_paddr += table_sizes[i];
+        table_vaddr += table_sizes[i];
     }
 
     xsdt->header.length = xsdt_size;
@@ -277,19 +280,21 @@ int make_guest_acpi_tables(vm_t *vm)
 
     // Copy all the tables to guest
     table_paddr = xsdt_addr;
+    table_vaddr = xsdt_vaddr;
     for (int i = 0; i < num_tables; i++) {
 
         // Need to fill in DSDT address
         if (i == fadt_index) {
-            fadt->dsdt_address = table_paddr - table_sizes[dsdt_index];
-            fadt->x_dsdt_address = table_paddr - table_sizes[dsdt_index];
+            fadt->dsdt_address = table_vaddr - table_sizes[dsdt_index];
+            fadt->x_dsdt_address = table_vaddr - table_sizes[dsdt_index];
             fadt->header.checksum = acpi_calc_checksum((char *)fadt, fadt_size);
         }
 
         ZF_LOGD("ACPI table \"%.4s\", addr = %p, size = %zu bytes\n",
-                (char *)tables[i], (void *)table_paddr, table_sizes[i]);
+                (char *)tables[i], (void *)table_vaddr, table_sizes[i]);
         memcpy((void *)table_paddr, (char *)tables[i], table_sizes[i]);
         table_paddr += table_sizes[i];
+        table_vaddr += table_sizes[i];
     }
 
     // RSDP
@@ -299,11 +304,11 @@ int make_guest_acpi_tables(vm_t *vm)
         .oem_id = "NICTA ",
         .revision = 2, /* ACPI v3*/
         .checksum = 0,
-        .rsdt_address = xsdt_addr,
+        .rsdt_address = xsdt_vaddr,
         /* rsdt_addrss will not be inspected as the xsdt is present.
            This is not ACPI 1 compliant */
         .length = sizeof(acpi_rsdp_t),
-        .xsdt_address = xsdt_addr,
+        .xsdt_address = xsdt_vaddr,
         .extended_checksum = 0,
         .reserved = {0}
     };