PCI: epf-test: Fix DMA transfer completion initialization

Reinitialize the transfer_complete DMA transfer completion before calling
tx_submit(), to avoid seeing the DMA transfer complete before the
completion is initialized, thus potentially losing the completion
notification.

Link: https://lore.kernel.org/r/[email protected]
Fixes: 8353813 ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Signed-off-by: Damien Le Moal <[email protected]>
Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Manivannan Sadhasivam <[email protected]>
Cc: [email protected]

Author: damien-lemoal

drivers/pci/endpoint/functions/pci-epf-test.c

@@ -151,10 +151,10 @@ static int pci_epf_test_data_transfer(struct pci_epf_test *epf_test,
 		return -EIO;
 	}
 
+	reinit_completion(&epf_test->transfer_complete);
 	tx->callback = pci_epf_test_dma_callback;
 	tx->callback_param = epf_test;
 	cookie = tx->tx_submit(tx);
-	reinit_completion(&epf_test->transfer_complete);
 
 	ret = dma_submit_error(cookie);
 	if (ret) {