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| author |   Andrii Nakryiko <andriin@fb.com> | 2020-06-19 16:16:57 -0700 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2020-06-22 17:01:48 -0700 |
| commit | b7ddfab20a6af3a0e366000eada63adf6a7683e7 (patch) | |
| tree | e98227b5a731328aa427e45e518f73fd403510b8 /tools/testing/selftests/bpf/progs/test_ksyms.c | |
| parent | libbpf: Add support for extracting kernel symbol addresses (diff) | |
| download | linux-dev-b7ddfab20a6af3a0e366000eada63adf6a7683e7.tar.xz linux-dev-b7ddfab20a6af3a0e366000eada63adf6a7683e7.zip | |
selftests/bpf: Add __ksym extern selftest
Validate libbpf is able to handle weak and strong kernel symbol externs in BPF
code correctly.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/bpf/20200619231703.738941-4-andriin@fb.com
Diffstat (limited to '')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_ksyms.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_ksyms.c b/tools/testing/selftests/bpf/progs/test_ksyms.c new file mode 100644 index 000000000000..6c9cbb5a3bdf --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_ksyms.c @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Facebook */ + +#include <stdbool.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +__u64 out__bpf_link_fops = -1; +__u64 out__bpf_link_fops1 = -1; +__u64 out__btf_size = -1; +__u64 out__per_cpu_start = -1; + +extern const void bpf_link_fops __ksym; +extern const void __start_BTF __ksym; +extern const void __stop_BTF __ksym; +extern const void __per_cpu_start __ksym; +/* non-existing symbol, weak, default to zero */ +extern const void bpf_link_fops1 __ksym __weak; + +SEC("raw_tp/sys_enter") +int handler(const void *ctx) +{ + out__bpf_link_fops = (__u64)&bpf_link_fops; + out__btf_size = (__u64)(&__stop_BTF - &__start_BTF); + out__per_cpu_start = (__u64)&__per_cpu_start; + + out__bpf_link_fops1 = (__u64)&bpf_link_fops1; + + return 0; +} + +char _license[] SEC("license") = "GPL"; |