From 09323b3bca95181c0da79daebc8b0603e500f573 Mon Sep 17 00:00:00 2001 From: Shay Agroskin Date: Mon, 23 Nov 2020 21:08:58 +0200 Subject: net: ena: set initial DMA width to avoid intel iommu issue The ENA driver uses the readless mechanism, which uses DMA, to find out what the DMA mask is supposed to be. If DMA is used without setting the dma_mask first, it causes the Intel IOMMU driver to think that ENA is a 32-bit device and therefore disables IOMMU passthrough permanently. This patch sets the dma_mask to be ENA_MAX_PHYS_ADDR_SIZE_BITS=48 before readless initialization in ena_device_init()->ena_com_mmio_reg_read_request_init(), which is large enough to workaround the intel_iommu issue. DMA mask is set again to the correct value after it's received from the device after readless is initialized. The patch also changes the driver to use dma_set_mask_and_coherent() function instead of the two pci_set_dma_mask() and pci_set_consistent_dma_mask() ones. Both methods achieve the same effect. Fixes: 1738cd3ed342 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)") Signed-off-by: Mike Cui Signed-off-by: Arthur Kiyanovski Signed-off-by: Shay Agroskin Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/amazon/ena/ena_netdev.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'drivers/net') diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c index 574c2b5ba21e..ec0008ba7751 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.c +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c @@ -3367,16 +3367,9 @@ static int ena_device_init(struct ena_com_dev *ena_dev, struct pci_dev *pdev, goto err_mmio_read_less; } - rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(dma_width)); + rc = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(dma_width)); if (rc) { - dev_err(dev, "pci_set_dma_mask failed 0x%x\n", rc); - goto err_mmio_read_less; - } - - rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(dma_width)); - if (rc) { - dev_err(dev, "err_pci_set_consistent_dma_mask failed 0x%x\n", - rc); + dev_err(dev, "dma_set_mask_and_coherent failed %d\n", rc); goto err_mmio_read_less; } @@ -4146,6 +4139,12 @@ static int ena_probe(struct pci_dev *pdev, const struct pci_device_id *ent) return rc; } + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(ENA_MAX_PHYS_ADDR_SIZE_BITS)); + if (rc) { + dev_err(&pdev->dev, "dma_set_mask_and_coherent failed %d\n", rc); + goto err_disable_device; + } + pci_set_master(pdev); ena_dev = vzalloc(sizeof(*ena_dev)); -- cgit v1.2.3