diff options
| author | Haggai Abramovsky <hagaya@mellanox.com> | 2016-05-04 14:50:15 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-05-05 23:23:05 -0400 |
| commit | 73898db0430125606c86c798c0627aefef9af9ed (patch) | |
| tree | 030372ba2bcf54a7d2ce4e0f0388bd41f03d0a6c /include/linux/mlx4 | |
| parent | 035cd6ba53eff060760c4f4d11339fcc916a967c (diff) | |
net/mlx4: Avoid wrong virtual mappings
The dma_alloc_coherent() function returns a virtual address which can
be used for coherent access to the underlying memory. On some
architectures, like arm64, undefined behavior results if this memory is
also accessed via virtual mappings that are not coherent. Because of
their undefined nature, operations like virt_to_page() return garbage
when passed virtual addresses obtained from dma_alloc_coherent(). Any
subsequent mappings via vmap() of the garbage page values are unusable
and result in bad things like bus errors (synchronous aborts in ARM64
speak).
The mlx4 driver contains code that does the equivalent of:
vmap(virt_to_page(dma_alloc_coherent)), this results in an OOPs when the
device is opened.
Prevent Ethernet driver to run this problematic code by forcing it to
allocate contiguous memory. As for the Infiniband driver, at first we
are trying to allocate contiguous memory, but in case of failure roll
back to work with fragmented memory.
Signed-off-by: Haggai Abramovsky <hagaya@mellanox.com>
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reported-by: David Daney <david.daney@cavium.com>
Tested-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/mlx4')
| -rw-r--r-- | include/linux/mlx4/device.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h index d1f904c8b2cb..80dec87a94f8 100644 --- a/include/linux/mlx4/device.h +++ b/include/linux/mlx4/device.h @@ -1058,7 +1058,7 @@ int mlx4_buf_alloc(struct mlx4_dev *dev, int size, int max_direct, void mlx4_buf_free(struct mlx4_dev *dev, int size, struct mlx4_buf *buf); static inline void *mlx4_buf_offset(struct mlx4_buf *buf, int offset) { - if (BITS_PER_LONG == 64 || buf->nbufs == 1) + if (buf->nbufs == 1) return buf->direct.buf + offset; else return buf->page_list[offset >> PAGE_SHIFT].buf + @@ -1098,7 +1098,7 @@ int mlx4_db_alloc(struct mlx4_dev *dev, struct mlx4_db *db, int order, void mlx4_db_free(struct mlx4_dev *dev, struct mlx4_db *db); int mlx4_alloc_hwq_res(struct mlx4_dev *dev, struct mlx4_hwq_resources *wqres, - int size, int max_direct); + int size); void mlx4_free_hwq_res(struct mlx4_dev *mdev, struct mlx4_hwq_resources *wqres, int size); |