Re: [PATCH 2/7] kvm-vfio: Decouple only when we match a group

From: Auger Eric
Date: Wed Jun 14 2017 - 08:32:07 EST


Hi Alex,

On 09/06/2017 23:59, Alex Williamson wrote:
> Unset-KVM and decrement-assignment only when we find the group in our
> list. Otherwise we can get out of sync if the user triggers this for
> groups that aren't currently on our list.
>
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> virt/kvm/vfio.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
This patch and 3/7 do not apply on 4.12-rc5 as there are small conflicts
with
commit 121f80ba68f1a5779a36d7b3247206e60e0a7418
KVM: PPC: VFIO: Add in-kernel acceleration for VFIO

Besides

Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>


Thanks

Eric
>
> diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c
> index d32f239eb471..db9036ef8c73 100644
> --- a/virt/kvm/vfio.c
> +++ b/virt/kvm/vfio.c
> @@ -201,18 +201,16 @@ static int kvm_vfio_set_group(struct kvm_device *dev, long attr, u64 arg)
> continue;
>
> list_del(&kvg->node);
> + kvm_arch_end_assignment(dev->kvm);
> + kvm_vfio_group_set_kvm(kvg->vfio_group, NULL);
> kvm_vfio_group_put_external_user(kvg->vfio_group);
> kfree(kvg);
> ret = 0;
> break;
> }
>
> - kvm_arch_end_assignment(dev->kvm);
> -
> mutex_unlock(&kv->lock);
>
> - kvm_vfio_group_set_kvm(vfio_group, NULL);
> -
> kvm_vfio_group_put_external_user(vfio_group);
>
> kvm_vfio_update_coherency(dev);
>