hw/arm/aspeed: Remove extraneous MemoryRegion object owner
I'm confused by this code, 'bmc' is created as: bmc = g_new0(AspeedBoardState, 1); Then we use it as QOM owner for different MemoryRegion objects. But looking at memory_region_init_ram (similarly for ROM): void memory_region_init_ram(MemoryRegion *mr, struct Object *owner, const char *name, uint64_t size, Error **errp) { DeviceState *owner_dev; Error *err = NULL; memory_region_init_ram_nomigrate(mr, owner, name, size, &err); if (err) { error_propagate(errp, err); return; } /* This will assert if owner is neither NULL nor a DeviceState. * We only want the owner here for the purposes of defining a * unique name for migration. TODO: Ideally we should implement * a naming scheme for Objects which are not DeviceStates, in * which case we can relax this restriction. */ owner_dev = DEVICE(owner); vmstate_register_ram(mr, owner_dev); } The expected assertion is not triggered ('bmc' is not NULL neither a DeviceState). 'bmc' structure is defined as: struct AspeedBoardState { AspeedSoCState soc; MemoryRegion ram_container; MemoryRegion max_ram; }; What happens is when using 'OBJECT(bmc)', the QOM macros cast the memory pointed by bmc, which first member is 'soc', which is initialized ...: object_initialize_child(OBJECT(machine), "soc", &bmc->soc, amc->soc_name); The 'soc' object is indeed a DeviceState, so the assertion passes. Since this is fragile and only happens to work by luck, remove the dangerous OBJECT(bmc) owner argument. Note, this probably breaks migration for this machine. Reviewed-by: NCédric Le Goater <clg@kaod.org> Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20200623072132.2868-2-f4bug@amsat.org Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
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