Add a test to ensure sleepable program is rejected by hash map iterator.
Signed-off-by: NHou Tao <houtao1@huawei.com>
Acked-by: NYonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220810080538.1845898-10-houtao@huaweicloud.comSigned-off-by: NAlexei Starovoitov <ast@kernel.org>