[PATCH] tracing: Use flexible array for entry fetch code
From: Rosen Penev <hidden>
Date: 2026-05-20 21:58:36
Store probe entry fetch instructions in the probe_entry_arg allocation instead of allocating a separate instruction array. This keeps the entry fetch code tied to the entry argument lifetime while leaving regular probe_arg instruction arrays separately allocated and freed. Assisted-by: Codex:GPT-5.5 Signed-off-by: Rosen Penev <redacted> --- kernel/trace/trace_probe.c | 8 +------- kernel/trace/trace_probe.h | 2 +- 2 files changed, 2 insertions(+), 8 deletions(-)
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index e0d3a0da26af..39f040c863e8 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c@@ -838,15 +838,10 @@ static int __store_entry_arg(struct trace_probe *tp, int argnum) int i, offset, last_offset = 0; if (!earg) { - earg = kzalloc_obj(*tp->entry_arg); + earg = kzalloc_flex(*earg, code, 2 * tp->nr_args + 1); if (!earg) return -ENOMEM; earg->size = 2 * tp->nr_args + 1; - earg->code = kzalloc_objs(struct fetch_insn, earg->size); - if (!earg->code) { - kfree(earg); - return -ENOMEM; - } /* Fill the code buffer with 'end' to simplify it */ for (i = 0; i < earg->size; i++) earg->code[i].op = FETCH_OP_END;
@@ -2051,7 +2046,6 @@ void trace_probe_cleanup(struct trace_probe *tp) traceprobe_free_probe_arg(&tp->args[i]); if (tp->entry_arg) { - kfree(tp->entry_arg->code); kfree(tp->entry_arg); tp->entry_arg = NULL; }
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 262d8707a3df..1076f1df347b 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h@@ -238,8 +238,8 @@ struct probe_arg { }; struct probe_entry_arg { - struct fetch_insn *code; unsigned int size; /* The entry data size */ + struct fetch_insn code[] __counted_by(size); }; struct trace_uprobe_filter {
--
2.54.0