From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933041AbaFCQXt (ORCPT ); Tue, 3 Jun 2014 12:23:49 -0400 Received: from cantor2.suse.de ([195.135.220.15]:44463 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932356AbaFCQXs (ORCPT ); Tue, 3 Jun 2014 12:23:48 -0400 From: Petr Mladek To: Steven Rostedt Cc: Frederic Weisbecker , Masami Hiramatsu , Jiri Kosina , linux-kernel@vger.kernel.org, x86@kernel.org, Petr Mladek Subject: [PATCH] ftrace/x86: Call text_ip_addr() instead of the duplicated code Date: Tue, 3 Jun 2014 18:23:21 +0200 Message-Id: <1401812601-2359-1-git-send-email-pmladek@suse.cz> X-Mailer: git-send-email 1.8.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I just went over this when looking at some Xen-related ftrace initialization problems. They were related to Xen code that is not upstream but this clean up would make sense here. I think that this was already the intention when text_ip_addr() was introduced in the commit 87fbb2ac6073a703930 (ftrace/x86: Use breakpoints for converting function graph caller). Anyway, better do it now before it shots people into their leg ;-) Signed-off-by: Petr Mladek --- arch/x86/kernel/ftrace.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 89de3eaf8772..cbc4a91b131e 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -297,16 +297,7 @@ int ftrace_int3_handler(struct pt_regs *regs) static int ftrace_write(unsigned long ip, const char *val, int size) { - /* - * On x86_64, kernel text mappings are mapped read-only with - * CONFIG_DEBUG_RODATA. So we use the kernel identity mapping instead - * of the kernel text mapping to modify the kernel text. - * - * For 32bit kernels, these mappings are same and we can use - * kernel identity mapping to modify code. - */ - if (within(ip, (unsigned long)_text, (unsigned long)_etext)) - ip = (unsigned long)__va(__pa_symbol(ip)); + ip = text_ip_addr(ip); if (probe_kernel_write((void *)ip, val, size)) return -EPERM; -- 1.8.4