Re: [Qemu-devel] [PATCH] memory.h: Improve IOMMU related documentation

[Peter Maydell]

On 30 April 2018 at 13:54, Paolo Bonzini <address@hidden> wrote:
> On 30/04/2018 14:24, Peter Maydell wrote:
>> -    /* Set this up to provide customized IOMMU replay function */
>> +    /* Set this up to provide customized IOMMU replay function.
>> +     * Optional method.
>> +     */
>>      void (*replay)(IOMMUMemoryRegion *iommu, IOMMUNotifier *notifier);
>
> replay is needed if you want to support IOMMU notifiers.  After
> memory_region_register_iommu_notifier you're only notified about future
> changes to the mappings; memory_region_iommu_replay calls the replay
> method so that the IOMMUNotifier is called for each existing mapping.

Is it then unrelated to record-and-replay ? That's what I guessed
it was for... Also, some IOMMUs (eg spapr_iommu.c) seem to support
notifiers but don't implement it.

thanks
-- PMM