Re: [Qemu-devel] [PATCH] dma: Define dma_context_memory and use in sysbus-ohci

[Paolo Bonzini <pbonzini@redhat.com>]

Il 13/11/2012 12:44, Peter Maydell ha scritto:
>>> >> As soon as Avi's iommu patches go in, in fact, dma->as will just be as.
>>> >> Even if as == NULL were to be outlawed and you'd be forced to write
>>> >> get_address_space_memory(), taking the pain to create dummy DMAContexts
>>> >> now is just not worth it.
>> >
>> > Personally I think it's better not to permit NULL DMAContexts or
>> > AddressSpaces here, because they're kind of a hack (in the same way
>> > that the "system address space" is kind of a hack). In real hardware
>> > you probably aren't really doing dma to that address space but to
>> > some more local bus. dma_context_memory/address_space_memory are
>> > nice and easy to search for, whereas NULL isn't. [And in general
>> > I think NULL is too easy to use; if you have to go looking for the
>> > system dma context you've been prompted to think about whether
>> > that's the right one...]
> Ping! Can we have a ruling on what the right fix for this is so
> we can fix these segfaults before 1.3 release, please?

I think this patch is already in Gerd's queue.

Paolo