Re: [Qemu-arm] [PATCH v1 1/6] memory: allow memory_region_register_iommu_notifier() to fail

[Peter Xu]

On Fri, Sep 13, 2019 at 10:36:10AM +0200, Eric Auger wrote:
> Currently, when a notifier is attempted to be registered and its
> flags are not supported (especially the MAP one) by the IOMMU MR,
> we generally abruptly exit in the IOMMU code. The failure could be
> handled more nicely in the caller and especially in the VFIO code.
> 
> So let's allow memory_region_register_iommu_notifier() to fail as
> well as notify_flag_changed() callback.
> 
> All sites implementing the callback are updated. This patch does
> not yet remove the exit(1) in the intel_iommu and amd_iommu code.

The idea looks sane to me, though how about using "Error **" instead
of returning int (or, both)?  Just like the majority of rest of QEMU.

Regards,

-- 
Peter Xu