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Date:   Wed, 13 Apr 2022 18:06:01 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Jason Gunthorpe <jgg@nvidia.com>
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Subject: Re: [PATCH 1/9] vfio: Make vfio_(un)register_notifier accept a
 vfio_device
Message-ID: <20220413160601.GA29631@lst.de>
References: <0-v1-a8faf768d202+125dd-vfio_mdev_no_group_jgg@nvidia.com> <1-v1-a8faf768d202+125dd-vfio_mdev_no_group_jgg@nvidia.com> <20220413055524.GB32092@lst.de> <20220413113952.GN2120790@nvidia.com>
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On Wed, Apr 13, 2022 at 08:39:52AM -0300, Jason Gunthorpe wrote:
> I already looked into that for a while, it is a real mess too because
> of how the notifiers are used by the current drivers, eg gvt assumes
> the notifier is called during its open_device callback to setup its
> kvm.

gvt very much expects kvm to be set before open and thus get the
cachup notifier, yes.  And given that this is how qemu uses
the ioctl I think we can actually simplify this further and require
vfio_group_set_kvm to be called before open for s390/ap as well and
do away with this whole mess.

> For this series I prefer to leave it alone

Ok, let's do it one step at a time.