From 37b06e5078975bb4efe3cbd91e254112851b125f Mon Sep 17 00:00:00 2001 From: Artemy Kovalyov Date: Tue, 27 Nov 2018 08:51:25 +0200 Subject: [PATCH] IB/mlx5: Fix implicit ODP interrupted page fault Since any page fault may be interrupted by a MMU invalidation and implicit leaf MR may be released during this process. The check for parent value is unreliable condition for an implicit MR. Use other condition that we can rely on to determine if MR is implicit. Fixes: b4cfe447d47b ("IB/mlx5: Implement on demand paging by adding support for MMU notifiers") Signed-off-by: Artemy Kovalyov Signed-off-by: Moni Shoua Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford --- drivers/infiniband/hw/mlx5/odp.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/infiniband/hw/mlx5/odp.c b/drivers/infiniband/hw/mlx5/odp.c index 2cc3d69ab6f6..4dc6cc640ce0 100644 --- a/drivers/infiniband/hw/mlx5/odp.c +++ b/drivers/infiniband/hw/mlx5/odp.c @@ -506,14 +506,13 @@ void mlx5_ib_free_implicit_mr(struct mlx5_ib_mr *imr) static int pagefault_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr, u64 io_virt, size_t bcnt, u32 *bytes_mapped) { + int npages = 0, current_seq, page_shift, ret, np; + bool implicit = false; struct ib_umem_odp *odp_mr = to_ib_umem_odp(mr->umem); u64 access_mask = ODP_READ_ALLOWED_BIT; - int npages = 0, page_shift, np; u64 start_idx, page_mask; struct ib_umem_odp *odp; - int current_seq; size_t size; - int ret; if (!odp_mr->page_list) { odp = implicit_mr_get_data(mr, io_virt, bcnt); @@ -521,7 +520,7 @@ static int pagefault_mr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr, if (IS_ERR(odp)) return PTR_ERR(odp); mr = odp->private; - + implicit = true; } else { odp = odp_mr; } @@ -600,7 +599,7 @@ next_mr: out: if (ret == -EAGAIN) { - if (mr->parent || !odp->dying) { + if (implicit || !odp->dying) { unsigned long timeout = msecs_to_jiffies(MMU_NOTIFIER_TIMEOUT);