[PATCH] net: vmxnet3: avoid accessing the data mapped to streaming DMA

[Jia-Ju Bai]

In vmxnet3_probe_device(), "adapter" is mapped to streaming DMA:
  adapter->adapter_pa = dma_map_single(..., adapter, ...);

Then "adapter" is accessed at many places in this function.

Theses accesses may cause data inconsistency between CPU cache and 
hardware.

To fix this problem, dma_map_single() is called after these accesses.

Signed-off-by: Jia-Ju Bai <baiji...@tsinghua.edu.cn>
---
 drivers/net/vmxnet3/vmxnet3_drv.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c 
b/drivers/net/vmxnet3/vmxnet3_drv.c
index ca395f9679d0..96a4c28ba429 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -3445,14 +3445,6 @@ vmxnet3_probe_device(struct pci_dev *pdev,
        }
 
        spin_lock_init(&adapter->cmd_lock);
-       adapter->adapter_pa = dma_map_single(&adapter->pdev->dev, adapter,
-                                            sizeof(struct vmxnet3_adapter),
-                                            PCI_DMA_TODEVICE);
-       if (dma_mapping_error(&adapter->pdev->dev, adapter->adapter_pa)) {
-               dev_err(&pdev->dev, "Failed to map dma\n");
-               err = -EFAULT;
-               goto err_set_mask;
-       }
        adapter->shared = dma_alloc_coherent(
                                &adapter->pdev->dev,
                                sizeof(struct Vmxnet3_DriverShared),
@@ -3628,6 +3620,16 @@ vmxnet3_probe_device(struct pci_dev *pdev,
        }
 
        vmxnet3_check_link(adapter, false);
+
+       adapter->adapter_pa = dma_map_single(&adapter->pdev->dev, adapter,
+                                            sizeof(struct vmxnet3_adapter),
+                                            PCI_DMA_TODEVICE);
+       if (dma_mapping_error(&adapter->pdev->dev, adapter->adapter_pa)) {
+               dev_err(&pdev->dev, "Failed to map dma\n");
+               err = -EFAULT;
+               goto err_register;
+       }
+
        return 0;
 
 err_register:
@@ -3655,8 +3657,6 @@ vmxnet3_probe_device(struct pci_dev *pdev,
                          sizeof(struct Vmxnet3_DriverShared),
                          adapter->shared, adapter->shared_pa);
 err_alloc_shared:
-       dma_unmap_single(&adapter->pdev->dev, adapter->adapter_pa,
-                        sizeof(struct vmxnet3_adapter), PCI_DMA_TODEVICE);
 err_set_mask:
        free_netdev(netdev);
        return err;
-- 
2.17.1