From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792437840; b=XNeRnYk7BUDFXPTujaEoCsrtA9mANn7BbuSccDjFqiF2rJAa896lzdOpE33/BUAtviEo HV5j+9ia2RIs0BONBFyoohaTl2kar57A56rc8t76yDpuQKk95egiWgbguo3G/k5REIpfJ u27gs8O1E4Sw5/iveCskilRBid8B1lkHx5s/X3BTrw1/M8hgIirHDUglhScQj3Zv208XT 6LNup19jEzttWAALwbdGPZxYZbD6BjVJSgXugmXsbbsCF1Dtte6jA3+G4aE3n0x3bykmN yjscKcJDb0Vwf4Puahdj9vPbpkWlw9eAjxaln57Az3wGStk/XqI1oloedPmuCtcq2iA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792437840; h=Received:DKIM-Signature:Received:Message-ID:User-Agent:Date:From:To: Cc:Subject:References:MIME-Version:Content-Type; bh=roAxgWJeGxuI12n/bhv6tcInHm/0UGxp9FTNXBEeZ7I=; b=X6aVvbDh5YI6zKQmaFGfBM6SSVjIRJAvSF34AemOKeWo+6Jw0CKKfbyNjFIF8fQjBgsO a6uVw1Cw84TECyZT7aSDXL8vfMCH/P4uk568K95DhdSGXFGhkIB9sx6o8Gcob10cvbNqx 1P1Kd7AUwdAw576DasInHW4hiUJ/VHYw/wO0uHf853ijbZjiSA2rGqYoiprLYqd3y5onW 80vMuFN9eEpPSFE6Dj8OxO1TB3BEppwwvZ7Eu+eo0UzQ6xD8hBfFWzzEQrBHmyJs75Xha /9QO7letvBKgOZebhrhVlVzfBpBjHuG/LyGuWZZbvji2ZhKiv7ee+4PPZmt3pDYow6Q== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Dybj4dh+; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 81B70606A31D for ; Mon, 19 Oct 2026 19:24:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Dybj4dh+ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5352D1F000C7; Mon, 19 Oct 2026 19:24:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792437840; bh=roAxgWJeGxuI12n/bhv6tcInHm/0UGxp9FTNXBEeZ7I=; h=Date:From:To:Cc:Subject:References; b=Dybj4dh+NuWyupjTl1UN0BAGZaIFrEhQ79YuXK+fUyCG4xRM3J19nZlJdFP1eLImm ybInyvyWQ9lGLPCML/Mr9iTJzwUptc96DfT+nrvPehHuhhy3LKAkSJXC4dckrfqIJo MVI5OeI3Irn/lkzuecOfUpqvK6ZBxGf+4XRG8XlmEyK13UDmCcevFth7CN2qPlNlkS XzlWSIXHZgyDIBHuu0egHsNadnPqSV2bhSM3Jq0H3HCWTbGbzlchMiFEYd1CvaXj2h 2jmfojOG0MDxMFQlIssxHPrSYAAb1z/1qmDJpK7qYwdVejkhFvCu86Os5gAHygvDD1 Iu7z4HBAEivhA== Received: from rostedt by gandalf with local (Exim 4.100.1) (envelope-from ) id 1xIsxj-00000001eFs-2Acx; Mon, 19 Oct 2026 15:23:59 -0400 Message-ID: <20261019192359.325485958@kernel.org> User-Agent: quilt/0.69 Date: Mon, 19 Oct 2026 15:23:46 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , pengdonglin Subject: [for-next][PATCH 2/9] tracing: Avoid BTF lookup in atomic context References: <20261019192344.004592683@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: pengdonglin 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 Signed-off-by: Steven Rostedt --- kernel/trace/trace_btf.c | 3 +++ 1 file changed, 3 insertions(+) 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; -- 2.53.0