From 6777829cfe1c4ed78319ad40aaee60254222da76 Mon Sep 17 00:00:00 2001 From: Greg Rose Date: Fri, 22 Jul 2011 05:46:07 +0000 Subject: [PATCH] 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 CC: Konrad Wilk Signed-off-by: Greg Rose Acked-by: Jesse Barnes Signed-off-by: Jeff Kirsher --- include/linux/pci.h | 2 ++ virt/kvm/assigned-dev.c | 2 ++ virt/kvm/iommu.c | 4 ++++ 3 files changed, 8 insertions(+) diff --git a/include/linux/pci.h b/include/linux/pci.h index f27893b3b724..d8c8573ecc21 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 4e9eaeb518c7..eaf3a50f9769 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 78c80f67f535..967aba133a62 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,