IB/mlx5: Change vma from shared to private

[ Upstream commit 1377661298d2820d675553d186c31b6f46c140d0 ]

Anonymous VMA (->vm_ops == NULL) cannot be shared, otherwise
it would lead to SIGBUS.

Remove the shared flags from the vma after we change it to be
anonymous.

This is easily reproduced by doing modprobe -r while running a
user-space application such as raw_ethernet_bw.

Fixes: 7c2344c3bbf97 ('IB/mlx5: Implements disassociate_ucontext API')
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 1502277..d7da1dc 100644 (file)
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -1323,6 +1323,7 @@ static void mlx5_ib_disassociate_ucontext(struct ib_ucontext *ibcontext)
                /* context going to be destroyed, should
                 * not access ops any more.
                 */
+               vma->vm_flags &= ~(VM_SHARED | VM_MAYSHARE);
                vma->vm_ops = NULL;
                list_del(&vma_private->list);
                kfree(vma_private);