pc: acpi-build: migrate RSDP table

Makes sure that RSDP stays the same
/i.e. matches ACPI tables blob in source/
if guest is migrated during RSDP reading or
has been already shadowed by firmware.

Fix applies only to new machine types starting
from 2.3, so it won't break migration for old
machine types.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 47368c92f28f634fc1389128e3a916ab881c80ff..693f44730ab92407396d6864241f09c60d11399f 100644 (file)
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -1651,15 +1651,21 @@ void acpi_setup(PcGuestInfo *guest_info)
     fw_cfg_add_file(guest_info->fw_cfg, ACPI_BUILD_TPMLOG_FILE,
                     tables.tcpalog->data, acpi_data_len(tables.tcpalog));
 
-    /*
-     * Though RSDP is small, its contents isn't immutable, so
-     * update it along with the rest of tables on guest access.
-     */
-    fw_cfg_add_file_callback(guest_info->fw_cfg, ACPI_BUILD_RSDP_FILE,
-                             acpi_build_update, build_state,
-                             tables.rsdp->data, acpi_data_len(tables.rsdp));
-
-    build_state->rsdp = tables.rsdp->data;
+    if (guest_info->has_immutable_rsdp) {
+        /*
+         * Keep for compatibility with old machine types.
+         * Though RSDP is small, its contents isn't immutable, so
+         * update it along with the rest of tables on guest access.
+         */
+        fw_cfg_add_file_callback(guest_info->fw_cfg, ACPI_BUILD_RSDP_FILE,
+                                 acpi_build_update, build_state,
+                                 tables.rsdp->data, acpi_data_len(tables.rsdp));
+        build_state->rsdp = tables.rsdp->data;
+    } else {
+        build_state->rsdp = qemu_get_ram_ptr(
+            acpi_add_rom_blob(build_state, tables.rsdp, ACPI_BUILD_RSDP_FILE, 0)
+        );
+    }
 
     qemu_register_reset(acpi_build_reset, build_state);
     acpi_build_reset(build_state);

diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index de75cf0e87909a14af323c22ee683408dd692e08..76744cf4f50e01e9bea5399f2f3d46fd389120cc 100644 (file)
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -60,6 +60,7 @@ static const int ide_iobase2[MAX_IDE_BUS] = { 0x3f6, 0x376 };
 static const int ide_irq[MAX_IDE_BUS] = { 14, 15 };
 
 static bool has_acpi_build = true;
+static bool has_immutable_rsdp;
 static int legacy_acpi_table_size;
 static bool smbios_defaults = true;
 static bool smbios_legacy_mode;
@@ -168,6 +169,7 @@ static void pc_init1(MachineState *machine,
 
     guest_info->isapc_ram_fw = !pci_enabled;
     guest_info->has_reserved_memory = has_reserved_memory;
+    guest_info->has_immutable_rsdp = has_immutable_rsdp;
 
     if (smbios_defaults) {
         MachineClass *mc = MACHINE_GET_CLASS(machine);
@@ -310,6 +312,7 @@ static void pc_init_pci(MachineState *machine)
 
 static void pc_compat_2_2(MachineState *machine)
 {
+    has_immutable_rsdp = true;
     x86_cpu_compat_set_features("kvm64", FEAT_1_EDX, 0, CPUID_VME);
     x86_cpu_compat_set_features("kvm32", FEAT_1_EDX, 0, CPUID_VME);
     x86_cpu_compat_set_features("Conroe", FEAT_1_EDX, 0, CPUID_VME);

diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 63027ee76bb79cf0ca318ef7648f7e9e01f8ce39..6151f2ffbe657dd65ec57aef06028523e871b83f 100644 (file)
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -50,6 +50,7 @@
 #define MAX_SATA_PORTS     6
 
 static bool has_acpi_build = true;
+static bool has_immutable_rsdp;
 static bool smbios_defaults = true;
 static bool smbios_legacy_mode;
 static bool smbios_uuid_encoded = true;
@@ -154,6 +155,7 @@ static void pc_q35_init(MachineState *machine)
     guest_info->isapc_ram_fw = false;
     guest_info->has_acpi_build = has_acpi_build;
     guest_info->has_reserved_memory = has_reserved_memory;
+    guest_info->has_immutable_rsdp = has_immutable_rsdp;
 
     /* Migration was not supported in 2.0 for Q35, so do not bother
      * with this hack (see hw/i386/acpi-build.c).
@@ -289,6 +291,7 @@ static void pc_q35_init(MachineState *machine)
 
 static void pc_compat_2_2(MachineState *machine)
 {
+    has_immutable_rsdp = true;
     x86_cpu_compat_set_features("kvm64", FEAT_1_EDX, 0, CPUID_VME);
     x86_cpu_compat_set_features("kvm32", FEAT_1_EDX, 0, CPUID_VME);
     x86_cpu_compat_set_features("Conroe", FEAT_1_EDX, 0, CPUID_VME);

diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index dddd2553896db18aa612b64281f62ec83bcdb418..85cc86a74f6d34f239b4901d30c7fce10bdb8611 100644 (file)
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -104,6 +104,7 @@ struct PcGuestInfo {
     int legacy_acpi_table_size;
     bool has_acpi_build;
     bool has_reserved_memory;
+    bool has_immutable_rsdp;
 };
 
 /* parallel.c */