On Wed, Feb 27, 2019 at 1:24 PM Yonghong Song <y...@fb.com> wrote:
>
> The bpf_map_lookup_elem is added in the bpf program.
> Without previous patch, the test change will trigger the
> following error:
> $ ./test_maps
> ...
> ; value_p = bpf_map_lookup_elem(map, &key);
> 20: (bf) r1 = r7
> 21: (bf) r2 = r8
> 22: (85) call bpf_map_lookup_elem#1
> ; if (!value_p || *value_p != 123)
> 23: (15) if r0 == 0x0 goto pc+16
> R0=map_value(id=2,off=0,ks=4,vs=4,imm=0) R6=inv1
> R7=map_ptr(id=0,off=0,ks=4,vs=4,imm=0)
> R8=fp-8,call_-1 R10=fp0,call_-1 fp-8=mmmmmmmm
> ; if (!value_p || *value_p != 123)
> 24: (61) r1 = *(u32 *)(r0 +0)
> R0=map_value(id=2,off=0,ks=4,vs=4,imm=0) R6=inv1
> R7=map_ptr(id=0,off=0,ks=4,vs=4,imm=0)
> R8=fp-8,call_-1 R10=fp0,call_-1 fp-8=mmmmmmmm
> bpf_spin_lock cannot be accessed directly by load/store
>
> With the kernel fix in the previous commit, the error goes away.
>
> Signed-off-by: Yonghong Song <y...@fb.com>
> ---
> tools/testing/selftests/bpf/progs/test_map_in_map.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/progs/test_map_in_map.c
> b/tools/testing/selftests/bpf/progs/test_map_in_map.c
> index ce923e67e08e..2985f262846e 100644
> --- a/tools/testing/selftests/bpf/progs/test_map_in_map.c
> +++ b/tools/testing/selftests/bpf/progs/test_map_in_map.c
> @@ -27,6 +27,7 @@ SEC("xdp_mimtest")
> int xdp_mimtest0(struct xdp_md *ctx)
> {
> int value = 123;
> + int *value_p;
> int key = 0;
> void *map;
>
> @@ -35,6 +36,9 @@ int xdp_mimtest0(struct xdp_md *ctx)
> return XDP_DROP;
>
> bpf_map_update_elem(map, &key, &value, 0);
> + value_p = bpf_map_lookup_elem(map, &key);
> + if (!value_p || *value_p != 123)
> + return XDP_DROP;
>
> map = bpf_map_lookup_elem(&mim_hash, &key);
> if (!map)
> --
> 2.17.1
>
LGTM.
Acked-by: Andrii Nakryiko <andr...@fb.com>
