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

[Michal Privoznik]

In v4.2.0-246-ged9e923c3c the SMM property was moved from PC
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.

Signed-off-by: Michal Privoznik <address@hidden>
---
 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);
-- 
2.24.1