The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1abe186ed8a6593069bc122da55fc684383fdc1c Mon Sep 17 00:00:00 2001
From: Moni Shoua monis@mellanox.com Date: Tue, 19 Mar 2019 11:24:36 +0200 Subject: [PATCH] IB/mlx5: Reset access mask when looping inside page fault handler
If page-fault handler spans multiple MRs then the access mask needs to be reset before each MR handling or otherwise write access will be granted to mapped pages instead of read-only.
Cc: stable@vger.kernel.org # 3.19 Fixes: 7bdf65d411c1 ("IB/mlx5: Handle page faults") Reported-by: Jerome Glisse jglisse@redhat.com Signed-off-by: Moni Shoua monis@mellanox.com Signed-off-by: Leon Romanovsky leonro@mellanox.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com
diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c index c20bfc41ecf1..0aa10ebda5d9 100644 --- a/drivers/infiniband/hw/mlx5/odp.c +++ b/drivers/infiniband/hw/mlx5/odp.c @@ -585,7 +585,7 @@ static int pagefault_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr, struct ib_umem_odp *odp_mr = to_ib_umem_odp(mr->umem); bool downgrade = flags & MLX5_PF_FLAGS_DOWNGRADE; bool prefetch = flags & MLX5_PF_FLAGS_PREFETCH; - u64 access_mask = ODP_READ_ALLOWED_BIT; + u64 access_mask; u64 start_idx, page_mask; struct ib_umem_odp *odp; size_t size; @@ -607,6 +607,7 @@ static int pagefault_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr, page_shift = mr->umem->page_shift; page_mask = ~(BIT(page_shift) - 1); start_idx = (io_virt - (mr->mmkey.iova & page_mask)) >> page_shift; + access_mask = ODP_READ_ALLOWED_BIT;
if (prefetch && !downgrade && !mr->umem->writable) { /* prefetch with write-access must