Re: [PATCH 1/2] stackleak: Update for arm64

From: Will Deacon
Date: Thu Feb 22 2018 - 11:58:39 EST


Hi Laura,

On Tue, Feb 20, 2018 at 05:13:02PM -0800, Laura Abbott wrote:
>
> arm64 has another layer of indirection in the RTL.
> Account for this in the plugin.
>
> Signed-off-by: Laura Abbott <labbott@xxxxxxxxxx>
> ---
> scripts/gcc-plugins/stackleak_plugin.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c
> index 6fc991c98d8b..7dfaa027423f 100644
> --- a/scripts/gcc-plugins/stackleak_plugin.c
> +++ b/scripts/gcc-plugins/stackleak_plugin.c
> @@ -244,6 +244,11 @@ static unsigned int stackleak_final_execute(void)
> * that insn.
> */
> body = PATTERN(insn);
> + /* arm64 is different */
> + if (GET_CODE(body) == PARALLEL) {
> + body = XEXP(body, 0);
> + body = XEXP(body, 0);
> + }

Like most kernel developers, I don't know the first thing about GCC internals
so I asked our GCC team and Richard (CC'd) reckons this should be:

if (GET_CODE(body) == PARALLEL)
body = XVECEXP(body, 0, 0);

instead of the hunk above. Can you give that a go instead, please?

Cheers,

Will