Hi Phil,
On 1/11/24 18:21, Philippe Mathieu-Daudé wrote:
On 11/1/24 08:30, Gavin Shan wrote:
On 1/11/24 16:47, Philippe Mathieu-Daudé wrote:
Per cpu_model_from_type() docstring (added in commit 445946f4dd):
* Returns: CPU model name or NULL if the CPU class doesn't exist
We must check the return value in order to avoid surprises, i.e.:
$ qemu-system-arm -machine virt -cpu cortex-a9
qemu-system-arm: Invalid CPU model: cortex-a9
The valid models are: cortex-a7, cortex-a15, (null), (null), (null), (null),
(null), (null), (null), (null), (null), (null), (null), max
Add assertions when the call can not fail (because the CPU type
must be registered).
Fixes: 5422d2a8fa ("machine: Print CPU model name instead of CPU type")
Reported-by: Peter Maydell <peter.mayd...@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org>
---
cpu-target.c | 1 +
hw/core/machine.c | 5 +++++
target/ppc/cpu_init.c | 1 +
3 files changed, 7 insertions(+)
diff --git a/cpu-target.c b/cpu-target.c
index 5eecd7ea2d..b0f6deb13b 100644
--- a/cpu-target.c
+++ b/cpu-target.c
@@ -291,6 +291,7 @@ static void cpu_list_entry(gpointer data, gpointer
user_data)
const char *typename = object_class_get_name(OBJECT_CLASS(data));
g_autofree char *model = cpu_model_from_type(typename);
+ assert(model);
if (cc->deprecation_note) {
qemu_printf(" %s (deprecated)\n", model);
} else {
diff --git a/hw/core/machine.c b/hw/core/machine.c
index fc239101f9..730ec10328 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -1422,16 +1422,21 @@ static bool is_cpu_type_supported(const MachineState
*machine, Error **errp)
/* The user specified CPU type isn't valid */
if (!mc->valid_cpu_types[i]) {
g_autofree char *requested =
cpu_model_from_type(machine->cpu_type);
+ assert(requested);
error_setg(errp, "Invalid CPU model: %s", requested);
if (!mc->valid_cpu_types[1]) {
g_autofree char *model = cpu_model_from_type(
mc->valid_cpu_types[0]);
+ assert(model);
error_append_hint(errp, "The only valid type is: %s\n",
model);
} else {
error_append_hint(errp, "The valid models are: ");
for (i = 0; mc->valid_cpu_types[i]; i++) {
g_autofree char *model = cpu_model_from_type(
mc->valid_cpu_types[i]);
+ if (!model) {
+ continue;
+ }
Shall we assert(model) for this case, to be consistent with other cases? :)
No, this is the "(null)" cases displayed in the example.
IOW, mc->valid_cpu_types[] contains a CPU type which isn't registered,
so we just skip it.
I thought this should be fixed by correcting mc->valid_cpu_types[] in
hw/arm/virt.c. It means the consistent mc->valid_cpu_types[] needs to
be provided by the specific board. Otherwise, the logic is incorrect from
the code level at least. For example, "cortex-a9" isn't available to
qemu-system-arm but it has been wrongly declared as supported in hw/arm/virt.c
I've posted one patch against it:
https://lists.nongnu.org/archive/html/qemu-arm/2024-01/msg00531.html
error_append_hint(errp, "%s%s",
model,
mc->valid_cpu_types[i + 1] ? ", " : "");
Otherwise, the separator here need to be adjusted because it's uncertain that
mc->valid_cpu_types[i+1] ... mc->valid_cpu_types[END] are valid.
Here we know mc->valid_cpu_types[i] is *not* NULL, but
mc->valid_cpu_types[i + 1] might be (signaling the end
of the array).
This seems correct to me, but I might be missing something.
When the class for mc->valid_cpu_types[i + 1] isn't registered, we will
skip the entry. it's possible that the class of mc->valid_cpu_types[i + 2]
isn't registered either. mc->valid_cpu_types[i + 3] to mc->valid_cpu_types[END
- 1]
have the similar situations.
In order to correct the separator, we need to invalidate the return value
from cpu_model_from_type(mc->valid_cpu_types[i + 1]) ...
cpu_model_from_type(mc->valid_cpu_types[END - 1]).
Too much complex for that and it's another reason why I suggested assert(model)
as above
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
index 344196a8ce..58f0c1e30e 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -7037,6 +7037,7 @@ static void ppc_cpu_list_entry(gpointer data, gpointer
user_data)
}
name = cpu_model_from_type(typename);
+ assert(name);
qemu_printf("PowerPC %-16s PVR %08x\n", name, pcc->pvr);
for (i = 0; ppc_cpu_aliases[i].alias != NULL; i++) {
PowerPCCPUAlias *alias = &ppc_cpu_aliases[i];
Thanks,
Gavin