Re: [Qemu-devel] [PATCH 3/3] qdev: Use qdev_device_add_get_class() for -device <type>, help

[Andreas Färber]

Hi Eduardo,

Am 01.11.2014 um 16:56 schrieb Eduardo Habkost:
> Make sure we try to list properties from classes that can be safely used with
> "-device".
> 
> Fixes the following crashes:
> 
>   $ qemu-system-x86_64 -device x86_64-cpu,help
>   **
>   ERROR:qom/object.c:336:object_initialize_with_type: assertion failed: 
> (type->abstract == false)
>   Aborted (core dumped)
>   $ qemu-system-x86_64 -device host-x86_64-cpu,help
>   qemu-system-x86_64: [...]/target-i386/cpu.c:1329: host_x86_cpu_initfn: 
> Assertion `(kvm_allowed)' failed.
>   Aborted (core dumped)
> 
> After applying this patch:
> 
>   $ qemu-system-x86_64 -device x86_64-cpu,help
>   Parameter 'driver' expects non-abstract device type
>   $ qemu-system-x86_64 -device host-x86_64-cpu,help
>   Parameter 'driver' expects pluggable device type
> 
> Signed-off-by: Eduardo Habkost <address@hidden>
> ---
>  qdev-monitor.c | 9 +++------
>  1 file changed, 3 insertions(+), 6 deletions(-)
> 
> diff --git a/qdev-monitor.c b/qdev-monitor.c
> index a9702d8..ebfa701 100644
> --- a/qdev-monitor.c
> +++ b/qdev-monitor.c
> @@ -235,12 +235,9 @@ int qdev_device_help(QemuOpts *opts)
>          return 0;
>      }
>  
> -    if (!object_class_by_name(driver)) {
> -        const char *typename = find_typename_by_alias(driver);
> -
> -        if (typename) {
> -            driver = typename;
> -        }
> +    qdev_get_device_class(&driver, &local_err);
> +    if (local_err) {
> +        goto error;
>      }
>  
>      prop_list = qmp_device_list_properties(driver, &local_err);

Is dc->cannot_instantiate_with_device_add_yet || (qdev_hotplug &&
!dc->hotpluggable) really relevant here? Or should that rather remain
outside the common function in 1/3?

Regards,
Andreas

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