Re: [PATCH] x86: Check for machine state object class before typecasting it

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 12/30/19 9:00 AM, Michal Privoznik wrote:
> In v4.2.0-246-ged9e923c3c the SMM property was moved from PC

Typo v4.2.0-246-ged9e923c3c -> ed9e923c3c.

> machine class to x86 machine class. Makes sense, but the change
> was too aggressive: in target/i386/kvm.c:kvm_arch_init() it
> altered check which sets SMRAM if given machine has SMM enabled.
> The line that detects whether given machine object is class of
> PC_MACHINE was removed from the check. This makes qemu try to
> enable SMRAM for all machine types, which is not what we want.
> 

Fixes: ed9e923c3c
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
> ---
>   target/i386/kvm.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
> index 0b511906e3..7ee3202634 100644
> --- a/target/i386/kvm.c
> +++ b/target/i386/kvm.c
> @@ -2173,6 +2173,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>       }
>   
>       if (kvm_check_extension(s, KVM_CAP_X86_SMM) &&
> +        object_dynamic_cast(OBJECT(ms), TYPE_X86_MACHINE) &&
>           x86_machine_is_smm_enabled(X86_MACHINE(ms))) {
>           smram_machine_done.notify = register_smram_listener;
>           qemu_add_machine_init_done_notifier(&smram_machine_done);
>