From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 814903093DF for ; Tue, 10 Mar 2026 14:35:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773153355; cv=none; b=K5nvOBpCnuVMq8NbOwIUagpkdb0E195H31cWb7Wa4A5E951VIipnHjCM17M1ZSDs4pI2ftUAZ2SL84SuRXU4J1areKjxH/ly4/vDMWKeYSPHe2++HSeX//P5veQnjCKwiB6pj0ZG80XJ/2wq8U3dQz49956xHm158RGUlMJWIKs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773153355; c=relaxed/simple; bh=Oah/ob0j+huqrwUcu7v1eD6ZGuXCp88sWFg298SA4N8=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=N9XVjpW3PTUndY0q//b5kRulstRgXr4HmGUo95RVmFAv3usUxODjTWVfFzokxJqBnsPKSIize1ED3Fwn3QQGKQIrP3o/4UjLM4I/3jz+C/kRcrvlbdj4ISlKTGggyDUQoE0FOGmRGloYLTB0AMamqQymFppMjodTTcVOGQCDbv0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Qf8AUJbi; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Qf8AUJbi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 584E7C2BCB1; Tue, 10 Mar 2026 14:35:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773153355; bh=Oah/ob0j+huqrwUcu7v1eD6ZGuXCp88sWFg298SA4N8=; h=Date:From:To:Cc:Subject:References:From; b=Qf8AUJbiosKllkJr9VqYU171ekjfOqenZlMXkQnLYjc/HKHes+657FT9gGM6DEPjg 5o88iONeB8oLr5FPNfwMvDeoABhAB8qI4DgKnOVlXnXmSReMddoY9t9HWLXxLV22bN RDm9vLeDxaxHrFOvLk00w3mCB668MQQ4ok7/o51FXmClH2ZN7RIULU7Uv//vlpUMEK acytsvAyqAe8EC2g2ocrDBuAvKCFwGCgmpsjK21QEbJ9lh3ofgO3kklh+o+nHvO0yP GttE/Nch7abxnp+NfR31HYNLE7c3bIihpifXPRRHxzqUGYqj2N0j4nQ8aoWsJF4q+R F3r4CxO3CTkJw== Received: from rostedt by gandalf with local (Exim 4.99.1) (envelope-from ) id 1vzyBp-00000002ZiH-1lXJ; Tue, 10 Mar 2026 10:36:05 -0400 Message-ID: <20260310143605.293978760@kernel.org> User-Agent: quilt/0.69 Date: Tue, 10 Mar 2026 10:35:33 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Vincent Donnefort Subject: [for-next][PATCH 18/18] tracing: Check for undefined symbols in simple_ring_buffer References: <20260310143515.132579088@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: Vincent Donnefort The simple_ring_buffer implementation must remain simple enough to be used by the pKVM hypervisor. Prevent the object build if unresolved symbols are found. Link: https://patch.msgid.link/20260309162516.2623589-19-vdonnefort@google.com Reviewed-by: Steven Rostedt (Google) Signed-off-by: Vincent Donnefort Signed-off-by: Steven Rostedt (Google) --- kernel/trace/Makefile | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index d106beca8d7f..3182e1bc1cf7 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -132,4 +132,20 @@ obj-$(CONFIG_TRACE_REMOTE) += trace_remote.o obj-$(CONFIG_SIMPLE_RING_BUFFER) += simple_ring_buffer.o obj-$(CONFIG_TRACE_REMOTE_TEST) += remote_test.o +# +# simple_ring_buffer is used by the pKVM hypervisor which does not have access +# to all kernel symbols. Fail the build if forbidden symbols are found. +# +UNDEFINED_ALLOWLIST := memset alt_cb_patch_nops __x86 __ubsan __asan __kasan __gcov __aeabi_unwind +UNDEFINED_ALLOWLIST += __stack_chk_fail stackleak_track_stack __ref_stack __sanitizer +UNDEFINED_ALLOWLIST := $(addprefix -e , $(UNDEFINED_ALLOWLIST)) + +quiet_cmd_check_undefined = NM $< + cmd_check_undefined = test -z "`$(NM) -u $< | grep -v $(UNDEFINED_ALLOWLIST)`" + +$(obj)/%.o.checked: $(obj)/%.o FORCE + $(call if_changed,check_undefined) + +always-$(CONFIG_SIMPLE_RING_BUFFER) += simple_ring_buffer.o.checked + libftrace-y := ftrace.o -- 2.51.0