Re: [PATCH bpf-next v1 2/2] selftests/bpf: Add test for static subprog call in lock cs

[Yonghong Song <yonghong.song@linux.dev>]

On 2/4/24 4:02 AM, Kumar Kartikeya Dwivedi wrote:
> Add selftests for static subprog calls within bpf_spin_lock critical
> section, and ensure we still reject global subprog calls. Also test the
> case where a subprog call will unlock the caller's held lock, or the
> caller will unlock a lock taken by a subprog call, ensuring correct
> transfer of lock state across frames on exit.
>
> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

LGTM with possible verifier message rewording from "function calls are
not allowed while holding a lock" to "global function calls are not
allowed ...".

Acked-by: Yonghong Song <yonghong.song@linux.dev>

> ---
>   .../selftests/bpf/prog_tests/spin_lock.c      |  2 +
>   .../selftests/bpf/progs/test_spin_lock.c      | 65 +++++++++++++++++++
>   .../selftests/bpf/progs/test_spin_lock_fail.c | 44 +++++++++++++
>   3 files changed, 111 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/spin_lock.c b/tools/testing/selftests/bpf/prog_tests/spin_lock.c
> index 18d451be57c8..6a4962ca0e5e 100644
> --- a/tools/testing/selftests/bpf/prog_tests/spin_lock.c
> +++ b/tools/testing/selftests/bpf/prog_tests/spin_lock.c
> @@ -48,6 +48,8 @@ static struct {
>   	{ "lock_id_mismatch_innermapval_kptr", "bpf_spin_unlock of different lock" },
>   	{ "lock_id_mismatch_innermapval_global", "bpf_spin_unlock of different lock" },
>   	{ "lock_id_mismatch_innermapval_mapval", "bpf_spin_unlock of different lock" },
> +	{ "lock_global_subprog_call1", "function calls are not allowed while holding a lock" },
> +	{ "lock_global_subprog_call2", "function calls are not allowed while holding a lock" },
>   };
>   
>   static int match_regex(const char *pattern, const char *string)
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