This is a note to let you know that I've just added the patch titled IB/mlx5: Avoid system crash when enabling many VFs to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ib-mlx5-avoid-system-crash-when-enabling-many-vfs.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From afd02cd3a9b6c04b41d946b5d7f6e17b3fc30c6b Mon Sep 17 00:00:00 2001 From: Eli Cohen <eli@xxxxxxxxxxxx> Date: Sun, 27 Nov 2016 15:18:21 +0200 Subject: IB/mlx5: Avoid system crash when enabling many VFs From: Eli Cohen <eli@xxxxxxxxxxxx> commit afd02cd3a9b6c04b41d946b5d7f6e17b3fc30c6b upstream. When enabling many VFs, the total amount of DMA mappings increase significantly. This causes DMA allocations to take a lot of time since they are serialized in the kernel. As a result the driver enters into fatal condition due to timeout and the system hangs. To recover from this we disable MR cache for VFs. PFs will still have a full cache and VFs cache can be manipulated as usual after driver load. Fixes: e126ba97dba9 ('mlx5: Add driver for Mellanox Connect-IB adapters') Signed-off-by: Eli Cohen <eli@xxxxxxxxxxxx> Signed-off-by: Maor Gottlieb <maorg@xxxxxxxxxxxx> Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx> Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/mlx5/mr.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/infiniband/hw/mlx5/mr.c +++ b/drivers/infiniband/hw/mlx5/mr.c @@ -628,7 +628,8 @@ int mlx5_mr_cache_init(struct mlx5_ib_de ent->order = i + 2; ent->dev = dev; - if (dev->mdev->profile->mask & MLX5_PROF_MASK_MR_CACHE) + if ((dev->mdev->profile->mask & MLX5_PROF_MASK_MR_CACHE) && + (mlx5_core_is_pf(dev->mdev))) limit = dev->mdev->profile->mr_cache[i].limit; else limit = 0; Patches currently in stable-queue which might be from eli@xxxxxxxxxxxx are queue-4.9/ib-mlx5-avoid-system-crash-when-enabling-many-vfs.patch queue-4.9/ib-mlx5-wait-for-all-async-command-completions-to-complete.patch queue-4.9/ib-mlx5-fix-reported-max-sge-calculation.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html