diff options
| author | pengdonglin <pengdonglin@xiaomi.com> | 2026-09-16 21:32:15 +0800 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2026-10-15 18:52:53 -0400 |
| commit | 42643ba35deb8ad1821acfc0577b445ee7ad7548 (patch) | |
| tree | e5f0b309b36cb2ae3e7fd7589b44b185a25b01db /kernel/trace | |
| parent | 5505be91c9413e52efcb37aea528d5699356e075 (diff) | |
tracing: Avoid BTF lookup in atomic context
The function graph trace formatter can be called from ftrace_dump_one()
with interrupts disabled. When ftrace_dump_on_oops is enabled, the trace
panic notifier can reach ftrace_dump() from the panic path, including the
nmi_panic() path used by the hard lockup detector.
btf_find_func_proto() calls bpf_find_btf_id(), which may initialize vmlinux
BTF under a mutex. Skip the BTF lookup when running in an atomic context
or with interrupts disabled, and fall back to the existing return value
formatting.
Link: https://patch.msgid.link/20260916133218.1282590-2-dolinux.peng@gmail.com
Fixes: ebeed8d4a555 ("tracing/probes: Move finding func-proto API and getting func-param API to trace_btf")
Signed-off-by: pengdonglin <pengdonglin@xiaomi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace_btf.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/trace/trace_btf.c b/kernel/trace/trace_btf.c index ee7a04886bf6..b8370ae9bd54 100644 --- a/kernel/trace/trace_btf.c +++ b/kernel/trace/trace_btf.c @@ -15,6 +15,9 @@ const struct btf_type *btf_find_func_proto(const char *func_name, struct btf **b const struct btf_type *t; s32 id; + if (unlikely(in_atomic() || irqs_disabled())) + return NULL; + id = bpf_find_btf_id(func_name, BTF_KIND_FUNC, btf_p); if (id < 0) return NULL; |