4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Huy Nguyen <huyn@xxxxxxxxxxxx> [ Upstream commit ca3d89a3ebe79367bd41b6b8ba37664478ae2dba ] enable_4k_uar module parameter was added in patch cited below to address the backward compatibility issue in SRIOV when the VM has system's PAGE_SIZE uar implementation and the Hypervisor has 4k uar implementation. The above compatibility issue does not exist in the non SRIOV case. In this patch, we always enable 4k uar implementation if SRIOV is not enabled on mlx4's supported cards. Fixes: 76e39ccf9c36 ("net/mlx4_core: Fix backward compatibility on VFs") Signed-off-by: Huy Nguyen <huyn@xxxxxxxxxxxx> Reviewed-by: Daniel Jurgens <danielj@xxxxxxxxxxxx> Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/mellanox/mlx4/main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/mellanox/mlx4/main.c +++ b/drivers/net/ethernet/mellanox/mlx4/main.c @@ -430,7 +430,7 @@ static int mlx4_dev_cap(struct mlx4_dev /* Virtual PCI function needs to determine UAR page size from * firmware. Only master PCI function can set the uar page size */ - if (enable_4k_uar) + if (enable_4k_uar || !dev->persist->num_vfs) dev->uar_page_shift = DEFAULT_UAR_PAGE_SHIFT; else dev->uar_page_shift = PAGE_SHIFT; @@ -2269,7 +2269,7 @@ static int mlx4_init_hca(struct mlx4_dev dev->caps.max_fmr_maps = (1 << (32 - ilog2(dev->caps.num_mpts))) - 1; - if (enable_4k_uar) { + if (enable_4k_uar || !dev->persist->num_vfs) { init_hca.log_uar_sz = ilog2(dev->caps.num_uars) + PAGE_SHIFT - DEFAULT_UAR_PAGE_SHIFT; init_hca.uar_page_sz = DEFAULT_UAR_PAGE_SHIFT - 12;