Re: [PATCH bpf-next v4 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:
- [Medium] The patch misses updating the architecture check in `tools/testing/selftests/bpf/progs/exceptions.c`, leaving stack argument exception tests permanently disabled on RV64.
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commit 064ba72e246734f0b6e1f3e1f7a66bfe6a3a8b0e
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.

> 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: Medium]
Should tools/testing/selftests/bpf/progs/exceptions.c also be updated 
with this new architecture guard?

It looks like the same has_stack_arg guard is used there:

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;

Without updating it, the C preprocessor will take the #else branch on RV64,
defining has_stack_arg = false. At runtime, prog_tests/exceptions.c checks 
skel->rodata->has_stack_arg and silently bypasses the stack argument exception 
tests.

Could this be added to ensure the exception tests are not permanently 
disabled on RV64?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260905070409.4141522-1-pulehui@huaweicloud.com?part=3