On Tue, Aug 06, 2024 at 06:27:54PM +0200, Rick Wertenbroek wrote: > The test for a DMA transfer was done in pci_epf_test_cmd_handler, which > if not supported would lead to the endpoint function just printing an > error message and waiting for further commands. This would leave the I guess it's the *test* that prints the error message? Is this the "Cannot transfer data using DMA" message? > host side PCI driver waiting for an interrupt because the call to > pci_epf_test_raise_irq is skipped. The host side driver > drivers/misc/pci_endpoint_test.c would hang indefinitely when sending > a transfer request with DMA if the endpoint does not support it. > This is because wait_for_completion() is used in the host side driver. > > Move the DMA check into the read/write/copy functions so that they > report a transfer (IO) error so that pci_epf_test_raise_irq() is > called when a transfer with DMA is requested, even if unsupported. Add "()" after function names above, as you did for pci_epf_test_raise_irq(). > The host side driver will still report an error on transfer thanks > to the checksum, because no data was moved, but will not hang anymore > waiting for an interrupt that will never arrive.
