Re: [PATCH bpf-next 3/5] selftests/bpf: don't mask result of bpf_csum_diff() in test_verifier

[Helge Deller <deller@xxxxxx>]

On 10/21/24 14:21, Puranjay Mohan wrote:
> The bpf_csum_diff() helper has been fixed to return a 16-bit value for
> all archs, so now we don't need to mask the result.
>
> ...
> --- a/tools/testing/selftests/bpf/progs/verifier_array_access.c
> +++ b/tools/testing/selftests/bpf/progs/verifier_array_access.c
> @@ -368,8 +368,7 @@ __naked void a_read_only_array_2_1(void)
>   	r4 = 0;						\
>   	r5 = 0;						\
>   	call %[bpf_csum_diff];				\
> -l0_%=:	r0 &= 0xffff;					\
> -	exit;						\
> +l0_%=:	exit;						\

Instead of dropping the masking, would it make sense to
check here if (r0 >> 16) == 0 ?

Helge