On 2/5/23 9:29 AM, Grant Seltzer Richman wrote:
On Sat, Feb 4, 2023 at 1:58 AM Martin KaFai Lau <martin.lau@xxxxxxxxx> wrote:
On 2/3/23 10:28 AM, Grant Seltzer wrote:
This patch changes the behavior of how BPF_PROG_RUN treats tracing
(fentry/fexit) programs. Previously only a return value is injected
but the actual program was not run.
hmm... I don't understand this. The actual program is run by attaching to the
bpf_fentry_test{1,2,3...}. eg. The test in fentry_test.c
I'm not sure what you mean. Are you saying in order to use the
BPF_PROG_RUN bpf syscall command the user must first attach to
`bpf_fentry_test1` (or any 1-8), and then execute the BPF_PROG_RUN?
It is how the fentry/fexit/fmod_ret...BPF_PROG_TYPE_TRACIN_xxx prog is setup to
run now in test_run. afaik, these tracing progs require the trampoline setup
before calling the bpf prog, so don't understand how __bpf_prog_test_run_tracing
will work safely.
A selftest will help how this will work without the traompline but may be first
need to understand what it is trying to solve.
