[net-next 1/8 v2] pci: Add flag indicating device has been assigned by KVM
flat view
From: Jeff Kirsher <hidden>
Date: 2011-09-23 16:18:59
Subsystem:
kernel virtual machine (kvm), pci subsystem, the rest · Maintainers:
Paolo Bonzini, Bjorn Helgaas, Linus Torvalds
From: Greg Rose <redacted> 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. -v2 Fixed comment based on feedback from Ian Campbell. CC: Ian Campbell <redacted> CC: Konrad Wilk <redacted> Signed-off-by: Greg Rose <redacted> Acked-by: Jesse Barnes <redacted> Signed-off-by: Jeff Kirsher <redacted> --- include/linux/pci.h | 2 ++ virt/kvm/assigned-dev.c | 2 ++ virt/kvm/iommu.c | 4 ++++ 3 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index f27893b..4f511da 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h@@ -174,6 +174,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG = (__force pci_dev_flags_t) 1, /* Device configuration is irrevocably lost if disabled into D3 */ PCI_DEV_FLAGS_NO_D3 = (__force pci_dev_flags_t) 2, + /* Provide indication device is assigned by a Virtual Machine Manager */ + PCI_DEV_FLAGS_ASSIGNED = (__force pci_dev_flags_t) 4, }; enum pci_irq_reroute_variant {
diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c
index 4e9eaeb..eaf3a50 100644
--- a/virt/kvm/assigned-dev.c
+++ b/virt/kvm/assigned-dev.c@@ -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);
diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c
index 78c80f6..967aba1 100644
--- a/virt/kvm/iommu.c
+++ b/virt/kvm/iommu.c@@ -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,
--
1.7.6.2