From: Damien Le Moal dlemoal@kernel.org
commit 933f31a2fe1f20e5b1ee065579f652cd1b317183 upstream.
pci_epf_test_data_transfer() and pci_epf_test_dma_callback() are not handling DMA transfer completion correctly, leading to completion notifications to the RC side that are too early. This problem can be detected when the RC side is running an IOMMU with messages such as:
pci-endpoint-test 0000:0b:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x001c address=0xfff00000 flags=0x0000]
When running the pcitest.sh tests: the address used for a previous test transfer generates the above error while the next test transfer is running.
Fix this by testing the DMA transfer status in pci_epf_test_dma_callback() and notifying the completion only when the transfer status is DMA_COMPLETE or DMA_ERROR. Furthermore, in pci_epf_test_data_transfer(), be paranoid and check again the transfer status and always call dmaengine_terminate_sync() before returning.
Link: https://lore.kernel.org/r/20230415023542.77601-5-dlemoal@kernel.org Fixes: 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities") Signed-off-by: Damien Le Moal dlemoal@kernel.org Signed-off-by: Lorenzo Pieralisi lpieralisi@kernel.org Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Manivannan Sadhasivam mani@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pci/endpoint/functions/pci-epf-test.c | 38 +++++++++++++------ 1 file changed, 27 insertions(+), 11 deletions(-)
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c index d65419735d2e..dbea6eb0dee7 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -54,6 +54,9 @@ struct pci_epf_test { struct delayed_work cmd_handler; struct dma_chan *dma_chan_tx; struct dma_chan *dma_chan_rx; + struct dma_chan *transfer_chan; + dma_cookie_t transfer_cookie; + enum dma_status transfer_status; struct completion transfer_complete; bool dma_supported; bool dma_private; @@ -85,8 +88,14 @@ static size_t bar_size[] = { 512, 512, 1024, 16384, 131072, 1048576 }; static void pci_epf_test_dma_callback(void *param) { struct pci_epf_test *epf_test = param; - - complete(&epf_test->transfer_complete); + struct dma_tx_state state; + + epf_test->transfer_status = + dmaengine_tx_status(epf_test->transfer_chan, + epf_test->transfer_cookie, &state); + if (epf_test->transfer_status == DMA_COMPLETE || + epf_test->transfer_status == DMA_ERROR) + complete(&epf_test->transfer_complete); }
/** @@ -120,7 +129,6 @@ static int pci_epf_test_data_transfer(struct pci_epf_test *epf_test, struct dma_async_tx_descriptor *tx; struct dma_slave_config sconf = {}; struct device *dev = &epf->dev; - dma_cookie_t cookie; int ret;
if (IS_ERR_OR_NULL(chan)) { @@ -152,25 +160,33 @@ static int pci_epf_test_data_transfer(struct pci_epf_test *epf_test, }
reinit_completion(&epf_test->transfer_complete); + epf_test->transfer_chan = chan; tx->callback = pci_epf_test_dma_callback; tx->callback_param = epf_test; - cookie = tx->tx_submit(tx); + epf_test->transfer_cookie = tx->tx_submit(tx);
- ret = dma_submit_error(cookie); + ret = dma_submit_error(epf_test->transfer_cookie); if (ret) { - dev_err(dev, "Failed to do DMA tx_submit %d\n", cookie); - return -EIO; + dev_err(dev, "Failed to do DMA tx_submit %d\n", ret); + goto terminate; }
dma_async_issue_pending(chan); ret = wait_for_completion_interruptible(&epf_test->transfer_complete); if (ret < 0) { - dmaengine_terminate_sync(chan); - dev_err(dev, "DMA wait_for_completion_timeout\n"); - return -ETIMEDOUT; + dev_err(dev, "DMA wait_for_completion interrupted\n"); + goto terminate; }
- return 0; + if (epf_test->transfer_status == DMA_ERROR) { + dev_err(dev, "DMA transfer failed\n"); + ret = -EIO; + } + +terminate: + dmaengine_terminate_sync(chan); + + return ret; }
struct epf_dma_filter {