It was originally intended as part of the work to split out the isapc machine
from the pc machine to restrict the isapc machine to using only 32-bit CPUs.
Before the 10.2 release it was decided in commit 329e36af94 ("hw/i386/isapc.c:
warn rather than reject modern x86 CPU models") to follow the official
deprecation process due to concerns this would have an adverse effect on users.
Now that the deprecation period has expired and there have been no reported
problems, update the isapc machine to reject modern x86 CPUs by reverting
commit 329e36af94 ("hw/i386/isapc.c: warn rather than reject modern x86 CPU
models").
Signed-off-by: Mark Cave-Ayland <[email protected]>
---
hw/i386/isapc.c | 53 +++++++++++++++++++++++++++++--------------------
1 file changed, 32 insertions(+), 21 deletions(-)
diff --git a/hw/i386/isapc.c b/hw/i386/isapc.c
index 1ba9ae22cc..44f4a44672 100644
--- a/hw/i386/isapc.c
+++ b/hw/i386/isapc.c
@@ -41,31 +41,29 @@ static void pc_init_isa(MachineState *machine)
DriveInfo *hd[MAX_IDE_BUS * MAX_IDE_DEVS];
int i;
- bool valid_cpu_type = false;
- static const char * const valid_cpu_types[] = {
- X86_CPU_TYPE_NAME("486"),
- X86_CPU_TYPE_NAME("athlon"),
- X86_CPU_TYPE_NAME("kvm32"),
- X86_CPU_TYPE_NAME("pentium"),
- X86_CPU_TYPE_NAME("pentium2"),
- X86_CPU_TYPE_NAME("pentium3"),
- X86_CPU_TYPE_NAME("qemu32"),
- };
-
/*
- * The isapc machine is supposed to represent a legacy ISA-only PC with a
- * 32-bit processor. For historical reasons the machine can still accept
- * almost any valid processor, but this is now deprecated in 10.2. Emit
- * a warning if anyone tries to use a deprecated CPU.
+ * There is a small chance that someone unintentionally passes "-cpu max"
+ * for the isapc machine, which will provide a much more modern 32-bit
+ * CPU than would be expected for an ISA-era PC. If the "max" cpu type has
+ * been specified, choose the "best" 32-bit cpu possible which we consider
+ * be the pentium3 (deliberately choosing an Intel CPU given that the
+ * default 486 CPU for the isapc machine is also an Intel CPU).
*/
- for (i = 0; i < ARRAY_SIZE(valid_cpu_types); i++) {
- if (!strcmp(machine->cpu_type, valid_cpu_types[i])) {
- valid_cpu_type = true;
- }
+ if (!strcmp(machine->cpu_type, X86_CPU_TYPE_NAME("max"))) {
+ machine->cpu_type = X86_CPU_TYPE_NAME("pentium3");
+ warn_report("-cpu max is invalid for isapc machine, using pentium3");
}
- if (!valid_cpu_type) {
- warn_report("cpu type %s is deprecated for isapc machine",
machine->cpu_type);
+ /*
+ * Similarly if someone unintentionally passes "-cpu host" for the isapc
+ * machine then display a warning and also switch to the "best" 32-bit
+ * cpu possible which we consider to be the pentium3. This is because any
+ * host CPU will already be modern than this, but it also ensures any
+ * newer CPU flags/features are filtered out for older guests.
+ */
+ if (!strcmp(machine->cpu_type, X86_CPU_TYPE_NAME("host"))) {
+ machine->cpu_type = X86_CPU_TYPE_NAME("pentium3");
+ warn_report("-cpu host is invalid for isapc machine, using pentium3");
}
if (machine->ram_size > 3.5 * GiB) {
@@ -156,6 +154,18 @@ static void pc_init_isa(MachineState *machine)
static void isapc_machine_options(MachineClass *m)
{
+ static const char * const valid_cpu_types[] = {
+ X86_CPU_TYPE_NAME("486"),
+ X86_CPU_TYPE_NAME("athlon"),
+ X86_CPU_TYPE_NAME("kvm32"),
+ X86_CPU_TYPE_NAME("pentium"),
+ X86_CPU_TYPE_NAME("pentium2"),
+ X86_CPU_TYPE_NAME("pentium3"),
+ X86_CPU_TYPE_NAME("qemu32"),
+ X86_CPU_TYPE_NAME("max"),
+ X86_CPU_TYPE_NAME("host"),
+ NULL
+ };
PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
m->desc = "ISA-only PC";
@@ -170,6 +180,7 @@ static void isapc_machine_options(MachineClass *m)
pcmc->has_reserved_memory = false;
m->default_nic = "ne2k_isa";
m->default_cpu_type = X86_CPU_TYPE_NAME("486");
+ m->valid_cpu_types = valid_cpu_types;
m->no_floppy = !module_object_class_by_name(TYPE_ISA_FDC);
m->no_parallel = !module_object_class_by_name(TYPE_ISA_PARALLEL);
}
--
2.43.0
