pci: Add flag indicating device has been assigned by KVM

Device drivers that create and destroy SR-IOV virtual functions via
calls to pci_enable_sriov() and pci_disable_sriov can cause catastrophic
failures if they attempt to destroy VFs while they are assigned to
guest virtual machines.  By adding a flag for use by the KVM module
to indicate that a device is assigned a device driver can check that
flag and avoid destroying VFs while they are assigned and avoid system
failures.

CC: Ian Campbell <[email protected]>
CC: Konrad Wilk <[email protected]>
Signed-off-by: Greg Rose <[email protected]>
Acked-by: Jesse Barnes <[email protected]>
Signed-off-by: Jeff Kirsher <[email protected]>
This commit is contained in:
Greg Rose 2011-07-22 05:46:07 +00:00 • committed by Jeff Kirsher
commit 6777829cfe
3 changed files with 8 additions and 0 deletions

View file

@ -205,6 +205,8 @@ static void kvm_free_assigned_device(struct kvm *kvm,
else
pci_restore_state(assigned_dev->dev);
assigned_dev->dev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
pci_release_regions(assigned_dev->dev);
pci_disable_device(assigned_dev->dev);
pci_dev_put(assigned_dev->dev);

View file

@ -187,6 +187,8 @@ int kvm_assign_device(struct kvm *kvm,
goto out_unmap;
}
pdev->dev_flags |= PCI_DEV_FLAGS_ASSIGNED;
printk(KERN_DEBUG "assign device %x:%x:%x.%x\n",
assigned_dev->host_segnr,
assigned_dev->host_busnr,
@ -215,6 +217,8 @@ int kvm_deassign_device(struct kvm *kvm,
iommu_detach_device(domain, &pdev->dev);
pdev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
printk(KERN_DEBUG "deassign device %x:%x:%x.%x\n",
assigned_dev->host_segnr,
assigned_dev->host_busnr,