diff options
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_core.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c index 87b288affc13..2e6409cc11ad 100644 --- a/drivers/vfio/pci/vfio_pci_core.c +++ b/drivers/vfio/pci/vfio_pci_core.c @@ -335,6 +335,17 @@ void vfio_pci_core_disable(struct vfio_pci_core_device *vdev) /* For needs_reset */ lockdep_assert_held(&vdev->vdev.dev_set->lock); + /* + * This function can be invoked while the power state is non-D0. + * This function calls __pci_reset_function_locked() which internally + * can use pci_pm_reset() for the function reset. pci_pm_reset() will + * fail if the power state is non-D0. Also, for the devices which + * have NoSoftRst-, the reset function can cause the PCI config space + * reset without restoring the original state (saved locally in + * 'vdev->pm_save'). + */ + vfio_pci_set_power_state(vdev, PCI_D0); + /* Stop the device from further DMA */ pci_clear_master(pdev); @@ -934,6 +945,19 @@ long vfio_pci_core_ioctl(struct vfio_device *core_vdev, unsigned int cmd, return -EINVAL; vfio_pci_zap_and_down_write_memory_lock(vdev); + + /* + * This function can be invoked while the power state is non-D0. + * If pci_try_reset_function() has been called while the power + * state is non-D0, then pci_try_reset_function() will + * internally set the power state to D0 without vfio driver + * involvement. For the devices which have NoSoftRst-, the + * reset function can cause the PCI config space reset without + * restoring the original state (saved locally in + * 'vdev->pm_save'). + */ + vfio_pci_set_power_state(vdev, PCI_D0); + ret = pci_try_reset_function(vdev->pdev); up_write(&vdev->memory_lock); @@ -2068,6 +2092,18 @@ static int vfio_pci_dev_set_hot_reset(struct vfio_device_set *dev_set, } cur_mem = NULL; + /* + * The pci_reset_bus() will reset all the devices in the bus. + * The power state can be non-D0 for some of the devices in the bus. + * For these devices, the pci_reset_bus() will internally set + * the power state to D0 without vfio driver involvement. + * For the devices which have NoSoftRst-, the reset function can + * cause the PCI config space reset without restoring the original + * state (saved locally in 'vdev->pm_save'). + */ + list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) + vfio_pci_set_power_state(cur, PCI_D0); + ret = pci_reset_bus(pdev); err_undo: @@ -2121,6 +2157,18 @@ static bool vfio_pci_dev_set_try_reset(struct vfio_device_set *dev_set) if (!pdev) return false; + /* + * The pci_reset_bus() will reset all the devices in the bus. + * The power state can be non-D0 for some of the devices in the bus. + * For these devices, the pci_reset_bus() will internally set + * the power state to D0 without vfio driver involvement. + * For the devices which have NoSoftRst-, the reset function can + * cause the PCI config space reset without restoring the original + * state (saved locally in 'vdev->pm_save'). + */ + list_for_each_entry(cur, &dev_set->device_list, vdev.dev_set_list) + vfio_pci_set_power_state(cur, PCI_D0); + ret = pci_reset_bus(pdev); if (ret) return false; |