3.16.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet <edumazet@xxxxxxxxxx> commit 3608b13ccc51d06e499dfe12b27f134de1286e28 upstream. Since mlx4 NIC are used on PowerPC with 64K pages, we need to adapt MLX4_EN_ALLOC_PREFER_ORDER definition. Otherwise, a fragment sitting in an out of order TCP queue can hold 0.5 Mbytes and it is a serious OOM risk. Fixes: 51151a16a60f ("mlx4: allow order-0 memory allocations in RX path") Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h @@ -98,7 +98,8 @@ /* Use the maximum between 16384 and a single page */ #define MLX4_EN_ALLOC_SIZE PAGE_ALIGN(16384) -#define MLX4_EN_ALLOC_PREFER_ORDER PAGE_ALLOC_COSTLY_ORDER +#define MLX4_EN_ALLOC_PREFER_ORDER min_t(int, get_order(32768), \ + PAGE_ALLOC_COSTLY_ORDER) /* Receive fragment sizes; we use at most 3 fragments (for 9600 byte MTU * and 4K allocations) */