From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:43908 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727092AbeLDK7N (ORCPT ); Tue, 4 Dec 2018 05:59:13 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , x86@kernel.org, stable@kernel.org, Masami Hiramatsu , "Steven Rostedt (VMware)" Subject: [PATCH 4.19 101/139] x86/function_graph: Simplify with function_graph_enter() Date: Tue, 4 Dec 2018 11:49:42 +0100 Message-Id: <20181204103654.662131418@linuxfoundation.org> In-Reply-To: <20181204103649.950154335@linuxfoundation.org> References: <20181204103649.950154335@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Rostedt (VMware) commit 07f7175b43827640d1e69c9eded89aa089a234b4 upstream. The function_graph_enter() function does the work of calling the function graph hook function and the management of the shadow stack, simplifying the work done in the architecture dependent prepare_ftrace_return(). Have x86 use the new code, and remove the shadow stack management as well as having to set up the trace structure. This is needed to prepare for a fix of a design bug on how the curr_ret_stack is used. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: x86@kernel.org Cc: stable@kernel.org Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback") Reviewed-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/ftrace.c | 15 +-------------- 1 file changed, 1 insertion(+), 14 deletions(-) --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -994,7 +994,6 @@ void prepare_ftrace_return(unsigned long { unsigned long old; int faulted; - struct ftrace_graph_ent trace; unsigned long return_hooker = (unsigned long) &return_to_handler; @@ -1046,19 +1045,7 @@ void prepare_ftrace_return(unsigned long return; } - trace.func = self_addr; - trace.depth = current->curr_ret_stack + 1; - - /* Only trace if the calling function expects to */ - if (!ftrace_graph_entry(&trace)) { + if (function_graph_enter(old, self_addr, frame_pointer, parent)) *parent = old; - return; - } - - if (ftrace_push_return_trace(old, self_addr, &trace.depth, - frame_pointer, parent) == -EBUSY) { - *parent = old; - return; - } } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */