Re: [PATCH bpf-next] arm64,bpf: Support struct arguments in the BPF trampoline

From: Yonghong Song
Date: Tue May 09 2023 - 09:38:55 EST

On 5/8/23 9:46 AM, Florent Revest wrote:
This extends the BPF trampoline JIT to support attachment to functions
that take small structures (up to 128bit) as argument. This is trivially
achieved by saving/restoring a number of "argument registers" rather
than a number of arguments.

The AAPCS64 section 6.8.2 describes the parameter passing ABI.
"Composite types" (like C structs) below 16 bytes (as enforced by the
BPF verifier) are provided as part of the 8 argument registers as
explained in the section C.12.

Signed-off-by: Florent Revest <revest@xxxxxxxxxxxx>
LGTM. Thanks for adding support for arm64!

Acked-by: Yonghong Song <yhs@xxxxxx>