[RFC bpf-next] bpf: Fix perf bpf event and audit prog id logging

[Jiri Olsa <jolsa@kernel.org>]

hi,
perf_event_bpf_event and bpf_audit_prog calls currently report zero
program id for unload path.

It's because of the [1] change moved those audit calls into work queue
and they are executed after the id is zeroed in bpf_prog_free_id.

I originally made a change that added 'id_audit' field to struct
bpf_prog, which would be initialized as id, untouched and used
in audit callbacks.

Then I realized we might actually not need to zero prog->aux->id
in bpf_prog_free_id. It seems to be called just once on release
paths. Tests seems ok with that.

thoughts?

thanks,
jirka


[1] d809e134be7a ("bpf: Prepare bpf_prog_put() to be called from irq context.")
---
 kernel/bpf/syscall.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index fdbae52f463f..426529355c29 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1991,7 +1991,6 @@ void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
 		__acquire(&prog_idr_lock);
 
 	idr_remove(&prog_idr, prog->aux->id);
-	prog->aux->id = 0;
 
 	if (do_idr_lock)
 		spin_unlock_irqrestore(&prog_idr_lock, flags);
-- 
2.38.1