Re: [PATCH bpf-next v5 3/3] selftests/bpf: Enable stack argument tests for RV64

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Missing architecture guard update for stack arguments in `tools/testing/selftests/bpf/progs/exceptions.c`.
--

commit 7ea892ecb0a3b4c34ad8033c7d6de54aaa01a98d
Author: Feng Jiang <jiangfeng@kylinos.cn>

selftests/bpf: Enable stack argument tests for RV64

Enable the stack argument selftests for RV64. The riscv guard is
restricted to __riscv_xlen == 64 since stack arguments are only
supported by the RV64 JIT. Keep the __BPF_FEATURE_STACK_ARGUMENT 
gate, defined by clang with BPF stack argument support [1].

[1] https://github.com/llvm/llvm-project/pull/189060

> diff --git a/tools/testing/selftests/bpf/progs/stack_arg.c b/tools/testing/selftests/bpf/progs/stack_arg.c
> index 944e3bb603e7e..3e9ed37c57bb9 100644
> --- a/tools/testing/selftests/bpf/progs/stack_arg.c
> +++ b/tools/testing/selftests/bpf/progs/stack_arg.c
> @@ -21,7 +21,8 @@ struct {
>  
>  int timer_result;
>  
> -#if (defined(__TARGET_ARCH_x86) || defined(__TARGET_ARCH_arm64)) && \
> +#if (defined(__TARGET_ARCH_x86) || defined(__TARGET_ARCH_arm64) || \
> +	(defined(__TARGET_ARCH_riscv) && __riscv_xlen == 64)) && \
>  	defined(__BPF_FEATURE_STACK_ARGUMENT)
>  
>  const volatile bool has_stack_arg = true;

[Severity: Low]
Does tools/testing/selftests/bpf/progs/exceptions.c also need this architecture
guard update?

The has_stack_arg macro in exceptions.c enables stack-argument-specific
exception tests. The RV64 architecture check seems to be omitted from that file
during this refactoring:

tools/testing/selftests/bpf/progs/exceptions.c:
#if (defined(__TARGET_ARCH_x86) || defined(__TARGET_ARCH_arm64)) \
	&& defined(__BPF_FEATURE_STACK_ARGUMENT)

const volatile bool has_stack_arg = true;

When exception support is eventually added for the RV64 JIT, the stack argument
portions of the exceptions selftest will silently fail to enable, reducing test
coverage.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260905085857.14143-1-pulehui@huaweicloud.com?part=3