From: Maor Gottlieb maorg@nvidia.com
commit ee27e330a953595903979ffdb84926843595a9fe upstream.
Fixes the below flow of sleeping in atomic context by releasing the RCU lock before calling to free_match_list.
build_match_list() <- disables preempt -> free_match_list() -> tree_put_node() -> down_write_ref_node() <- take write lock
Fixes: 693c6883bbc4 ("net/mlx5: Add hash table for flow groups in flow table") Reported-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Maor Gottlieb maorg@nvidia.com Signed-off-by: Saeed Mahameed saeedm@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/mellanox/mlx5/core/fs_core.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c @@ -1558,9 +1558,9 @@ static int build_match_list(struct match
curr_match = kmalloc(sizeof(*curr_match), GFP_ATOMIC); if (!curr_match) { + rcu_read_unlock(); free_match_list(match_head); - err = -ENOMEM; - goto out; + return -ENOMEM; } if (!tree_get_node(&g->node)) { kfree(curr_match); @@ -1569,7 +1569,6 @@ static int build_match_list(struct match curr_match->g = g; list_add_tail(&curr_match->list, &match_head->list); } -out: rcu_read_unlock(); return err; }