Patch "kvm-vfio: Decouple only when we match a group" has been added to the 4.12-stable tree

Patch "kvm-vfio: Decouple only when we match a group" has been added to the 4.12-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    kvm-vfio: Decouple only when we match a group

to the 4.12-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     kvm-vfio-decouple-only-when-we-match-a-group.patch
and it can be found in the queue-4.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From e323369b2e204da4dc771bbddceef986f4bf85d5 Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@redhat.com>
Date: Wed, 28 Jun 2017 13:49:52 -0600
Subject: kvm-vfio: Decouple only when we match a group

From: Alex Williamson <alex.williamson@redhat.com>

commit e323369b2e204da4dc771bbddceef986f4bf85d5 upstream.

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@redhat.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 virt/kvm/vfio.c |   13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

--- a/virt/kvm/vfio.c
+++ b/virt/kvm/vfio.c
@@ -246,21 +246,20 @@ static int kvm_vfio_set_group(struct kvm
 				continue;
 
 			list_del(&kvg->node);
+			kvm_arch_end_assignment(dev->kvm);
+#ifdef CONFIG_SPAPR_TCE_IOMMU
+			kvm_spapr_tce_release_vfio_group(dev->kvm,
+							 kvg->vfio_group);
+#endif
+			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);
 
-#ifdef CONFIG_SPAPR_TCE_IOMMU
-		kvm_spapr_tce_release_vfio_group(dev->kvm, vfio_group);
-#endif
-		kvm_vfio_group_set_kvm(vfio_group, NULL);
-
 		kvm_vfio_group_put_external_user(vfio_group);
 
 		kvm_vfio_update_coherency(dev);


Patches currently in stable-queue which might be from alex.williamson@redhat.com are

queue-4.12/kvm-vfio-decouple-only-when-we-match-a-group.patch