On Wed, Nov 24, 2021 at 01:48:09PM -0800, Andrii Nakryiko wrote:

On Thu, Nov 18, 2021 at 3:25 AM Jiri Olsa [off-list ref] wrote:

quoted

Keeping active attached trampoline in bpf_prog so it can be used
in following changes to account for multiple functions attachments
in program.

As EXT programs are not going to be supported in multiple functions
attachment for now, I'm keeping them stored in link.

can the same EXT program be attached twice? If not, why can't you just
use the same prog->aux->trampoline instead of the if/else everywhere?

I recall that was my initial change, but it was clashing with
fentry/fexit programs because extensions are special

I'll re-check and try to make this generic

jirka

quoted

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 include/linux/bpf.h  |  1 +
 kernel/bpf/syscall.c | 34 +++++++++++++++++++++++++++++-----
 2 files changed, 30 insertions(+), 5 deletions(-)