This is necessary because during reboot of a VM the assigned devices continue DMA transfers which causes memory corruption.
Signed-off-by: Thomas Ostler <thomas.ost...@nsn.com> Signed-off-by: Bernhard Kohl <bernhard.k...@nsn.com> --- Sorry for for the long delay. Finally we added Alex' suggestions and rebased the patch. Thanks Bernhard --- hw/device-assignment.c | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-) diff --git a/hw/device-assignment.c b/hw/device-assignment.c index 5f5bde1..3f8de66 100644 --- a/hw/device-assignment.c +++ b/hw/device-assignment.c @@ -1434,6 +1434,17 @@ static void assigned_dev_unregister_msix_mmio(AssignedDevice *dev) dev->msix_table_page = NULL; } +static void reset_assigned_device(DeviceState *dev) +{ + PCIDevice *d = DO_UPCAST(PCIDevice, qdev, dev); + uint32_t conf; + + /* reset the bus master bit to avoid further DMA transfers */ + conf = assigned_dev_pci_read_config(d, PCI_COMMAND, 2); + conf &= ~PCI_COMMAND_MASTER; + assigned_dev_pci_write_config(d, PCI_COMMAND, conf, 2); +} + static int assigned_initfn(struct PCIDevice *pci_dev) { AssignedDevice *dev = DO_UPCAST(AssignedDevice, dev, pci_dev); @@ -1544,6 +1555,7 @@ static PCIDeviceInfo assign_info = { .qdev.name = "pci-assign", .qdev.desc = "pass through host pci devices to the guest", .qdev.size = sizeof(AssignedDevice), + .qdev.reset = reset_assigned_device, .init = assigned_initfn, .exit = assigned_exitfn, .config_read = assigned_dev_pci_read_config, -- 1.7.2.3