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From 8c5380844c8f52663f497609cfb0a833e5f643e0 Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@redhat.com>
Date: Thu, 14 Dec 2017 16:30:06 +0100
Subject: [PATCH 6/6] vfio: Fix vfio-kvm group registration

RH-Author: Alex Williamson <alex.williamson@redhat.com>
Message-id: <20171214162725.10938.41443.stgit@gimli.home>
Patchwork-id: 78402
O-Subject: [RHEL-7.5 qemu-kvm-rhev PATCH] vfio: Fix vfio-kvm group registration
Bugzilla: 1520294
RH-Acked-by: Auger Eric <eric.auger@redhat.com>
RH-Acked-by: Peter Xu <peterx@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

Commit 8c37faa475f3 ("vfio-pci, ppc64/spapr: Reorder group-to-container
attaching") moved registration of groups with the vfio-kvm device from
vfio_get_group() to vfio_connect_container(), but it missed the case
where a group is attached to an existing container and takes an early
exit.  Perhaps this is a less common case on ppc64/spapr, but on x86
(without viommu) all groups are connected to the same container and
thus only the first group gets registered with the vfio-kvm device.
This becomes a problem if we then hot-unplug the devices associated
with that first group and we end up with KVM being misinformed about
any vfio connections that might remain.  Fix by including the call to
vfio_kvm_device_add_group() in this early exit path.

Fixes: 8c37faa475f3 ("vfio-pci, ppc64/spapr: Reorder group-to-container attaching")
Cc: qemu-stable@nongnu.org # qemu-2.10+
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
(cherry picked from commit 2016986aedb6ea2839662eb5f60630f3e231bd1a)
---

Testing: hot unplug Intel 82576 PF which is not the first vfio-pci device
for the VM.  Previous, libvirt log includes:

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/vfio/common.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 7b2924c..7007878 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -968,6 +968,7 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
         if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
             group->container = container;
             QLIST_INSERT_HEAD(&container->group_list, group, container_next);
+            vfio_kvm_device_add_group(group);
             return 0;
         }
     }
-- 
1.8.3.1