Re: [PATCH bpf-next v5 10/11] selftests/bpf: Add inline-asm and subprog tests for R0:R2 returns

[Eduard Zingerman <eddyz87@gmail.com>]

On Thu, 2026-08-13 at 13:03 -0700, Yonghong Song wrote:

...

> diff --git a/tools/testing/selftests/bpf/progs/aggregate_ret_func.c b/tools/testing/selftests/bpf/progs/aggregate_ret_func.c
> new file mode 100644
> index 000000000000..cfb21bcf704b
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/aggregate_ret_func.c

...

> +struct ptr_pair {
> +	void *p;
> +	__u64 x;
> +};
> +
> +static __naked __noinline struct ptr_pair static_ret_ptr_pair(void)
> +{
> +	asm volatile (
> +	"r0 = 0;"
> +	"r2 = r1;"
> +	"exit;"
> +	);
> +}
> +
> +SEC("tc")
> +__load_if_JITed()
> +__success __retval(0)
> +__naked int aggregate_ret_static_ptr_pair(void)

This test is redundant, already covered by a previous patch.

> +{
> +	asm volatile (
> +	"call %[static_ret_ptr_pair];"
> +	"r1 = *(u32 *)(r2 + 0);"	/* deref the returned ctx pointer */
> +	"r0 = 0;"
> +	"exit;"
> +	:
> +	: __imm(static_ret_ptr_pair)
> +	: __clobber_all);
> +}
> +
> +char _license[] SEC("license") = "GPL";

...

> diff --git a/tools/testing/selftests/bpf/progs/aggregate_ret_kfunc_c.c b/tools/testing/selftests/bpf/progs/aggregate_ret_kfunc_c.c
> index b66576307f73..2c1889fc28ef 100644
> --- a/tools/testing/selftests/bpf/progs/aggregate_ret_kfunc_c.c
> +++ b/tools/testing/selftests/bpf/progs/aggregate_ret_kfunc_c.c
> @@ -50,6 +50,66 @@ int aggregate_ret_kfunc_struct_c_test(struct __sk_buff *skb)

> +int aggregate_ret_kfunc_li_c_test(struct __sk_buff *skb)
...
> +int aggregate_ret_kfunc_ii_c_test(struct __sk_buff *skb)
...
> +int aggregate_ret_kfunc_uu_c_test(struct __sk_buff *skb)

I don't think three tests above a warranted, the previous patch
already tested returning 16-byte structs. Maybe a test with a small
structs of two ints, but I'd skip even that.
This would drop a ton of code from the back of the patch.

...