Re: [PATCH bpf v2 2/2] selftests/bpf: cover the exception callback using its own BPF stack

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Multi-line comment does not follow the required BPF kernel comment style.
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commit 6cf0d756f3e18b0c62e71081cda78a62eb981a75
Author: Donggeun Yoo <donggeunyoo.kernel@gmail.com>

selftests/bpf: cover the exception callback using its own BPF stack

This commit adds a test to verify that an exception callback can safely
access its own BPF stack slot. It introduces a subprogram that throws an
exception and uses a callback that passes a local variable's address to
bpf_probe_read_kernel().

> diff --git a/tools/testing/selftests/bpf/progs/exceptions.c b/tools/testing/selftests/bpf/progs/exceptions.c
> index c8d716fbd4191..2b01b45cef06a 100644
> --- a/tools/testing/selftests/bpf/progs/exceptions.c
> +++ b/tools/testing/selftests/bpf/progs/exceptions.c
[ ... ]
> @@ -212,6 +212,35 @@ int exception_throw_subprog(struct __sk_buff *ctx)
>  	return 0;
>  }
>  
> +u64 exception_cb_stack_src = 0x1234;
> +
> +/* The address handed to the helper has to be this callback's own stack
> + * slot, not one from a frame that is already gone.
> + */

[Severity: Low]
Could we update this comment block in exception_cb_stack() to follow the 
preferred BPF multi-line comment style?

The BPF subsystem guidelines require the opening '/*' to be on its own line
for multi-line comments:

/*
 * The address handed to the helper has to be this callback's own stack
 * slot, not one from a frame that is already gone.
 */

> +__noinline int exception_cb_stack(u64 cookie)
> +{
> +	volatile u64 val = 0xdead;
> +
> +	bpf_probe_read_kernel((void *)&val, sizeof(val), &exception_cb_stack_src);
> +	return val;
> +}

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Sashiko AI review · https://sashiko.dev/#/patchset/20260907054235.473103-1-donggeunyoo.kernel@gmail.com?part=2