Re: [RESEND PATCH v8 04/11] bus: platform, amba, fsl-mc, PCI: Add device DMA ownership management

[Jason Gunthorpe <jgg@nvidia.com>]

On Mon, Jun 26, 2023 at 09:02:40PM +0800, Zenghui Yu wrote:

> It looks like on device probe, with DEBUG_TEST_DRIVER_REMOVE,
> .dma_configure() will be executed *twice* via the
> really_probe()/re_probe path, and *no* .dma_cleanup() will be executed.
> The resulting dev::iommu_group::owner_cnt is 2, which will confuse the
> later iommu_group_dma_owner_claimed() call from VFIO on guest startup.

Does this work for you?

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 9c09ca5c4ab68e..7145d9b940b14b 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -693,6 +693,8 @@ static int really_probe(struct device *dev, struct device_driver *drv)
 
 		device_remove(dev);
 		driver_sysfs_remove(dev);
+		if (dev->bus && dev->bus->dma_cleanup)
+			dev->bus->dma_cleanup(dev);
 		device_unbind_cleanup(dev);
 
 		goto re_probe;