This is a note to let you know that I've just added the patch titled
PCI: epf-test: Fix DMA transfer completion detection
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-epf-test-fix-dma-transfer-completion-detection.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 933f31a2fe1f20e5b1ee065579f652cd1b317183 Mon Sep 17 00:00:00 2001
From: Damien Le Moal <dlemoal@xxxxxxxxxx>
Date: Sat, 15 Apr 2023 11:35:29 +0900
Subject: PCI: epf-test: Fix DMA transfer completion detection
From: Damien Le Moal <dlemoal@xxxxxxxxxx>
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@xxxxxxxxxx
Fixes: 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Signed-off-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/pci/endpoint/functions/pci-epf-test.c | 36 ++++++++++++++++++--------
1 file changed, 26 insertions(+), 10 deletions(-)
--- 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, 1
static void pci_epf_test_dma_callback(void *param)
{
struct pci_epf_test *epf_test = param;
+ struct dma_tx_state state;
- complete(&epf_test->transfer_complete);
+ 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(st
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(st
}
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;
+ }
+
+ if (epf_test->transfer_status == DMA_ERROR) {
+ dev_err(dev, "DMA transfer failed\n");
+ ret = -EIO;
}
- return 0;
+terminate:
+ dmaengine_terminate_sync(chan);
+
+ return ret;
}
struct epf_dma_filter {
Patches currently in stable-queue which might be from dlemoal@xxxxxxxxxx are
queue-6.4/pci-epf-test-fix-dma-transfer-completion-detection.patch
queue-6.4/pci-rockchip-use-u32-variable-to-access-32-bit-registers.patch
queue-6.4/pci-rockchip-assert-pci-configuration-enable-bit-after-probe.patch
queue-6.4/pci-rockchip-fix-legacy-irq-generation-for-rk3399-pcie-endpoint-core.patch
queue-6.4/pci-epf-test-fix-dma-transfer-completion-initialization.patch
queue-6.4/pci-rockchip-add-poll-and-timeout-to-wait-for-phy-plls-to-be-locked.patch
queue-6.4/pci-rockchip-write-pci-device-id-to-correct-register.patch
queue-6.4/pci-rockchip-set-address-alignment-for-endpoint-mode.patch
