Re: virtio-iommu hotplug issue

From: Jean-Philippe Brucker
Date: Fri Apr 14 2023 - 11:18:07 EST


On Thu, Apr 13, 2023 at 08:01:54PM +0900, Akihiko Odaki wrote:
> Yes, that's right. The guest can dynamically create and delete VFs. The
> device is emulated by QEMU: igb, an Intel NIC recently added to QEMU and
> projected to be released as part of QEMU 8.0.

Ah great, that's really useful, I'll add it to my tests

> > Yes, I think this is an issue in the virtio-iommu driver, which should be
> > sending a DETACH request when the VF is disabled, likely from
> > viommu_release_device(). I'll work on a fix unless you would like to do it
>
> It will be nice if you prepare a fix. I will test your patch with my
> workload if you share it with me.

I sent a fix:
https://lore.kernel.org/linux-iommu/20230414150744.562456-1-jean-philippe@xxxxxxxxxx/

Thank you for reporting this, it must have been annoying to debug

Thanks,
Jean