Re: [PATCH v3 1/7] memory: associate DMA accesses with the initiator Device

[Alexander Bulekov]

On 221115 1119, Peter Xu wrote:
> On Fri, Oct 28, 2022 at 03:16:42PM -0400, Alexander Bulekov wrote:
> > +    /* Do not allow more than one simultanous access to a device's IO 
> > Regions */
> > +    if (mr->owner &&
> > +            !mr->ram_device && !mr->ram && !mr->rom_device && 
> > !mr->readonly) {
> > +        dev = (DeviceState *) object_dynamic_cast(mr->owner, TYPE_DEVICE);
> > +        if (dev->mem_reentrancy_guard.engaged_in_io) {
> 
> Do we need to check dev being non-NULL?  Fundamentally it's about whether
> the owner can be not a DeviceState, I believe it's normally true but I
> can't tell; at least from memory region API it can be any Object*.
> 

I'll add a NULL-check
Thanks