From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760998AbXGCQlm (ORCPT ); Tue, 3 Jul 2007 12:41:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760872AbXGCQlX (ORCPT ); Tue, 3 Jul 2007 12:41:23 -0400 Received: from smtp.polymtl.ca ([132.207.4.11]:44671 "EHLO smtp.polymtl.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761034AbXGCQlU (ORCPT ); Tue, 3 Jul 2007 12:41:20 -0400 Message-Id: <20070703164031.888938670@polymtl.ca> References: <20070703163818.785635235@polymtl.ca> User-Agent: quilt/0.46-1 Date: Tue, 03 Jul 2007 12:38:22 -0400 From: Mathieu Desnoyers To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org Cc: Mathieu Desnoyers , prasanna@in.ibm.com, ananth@in.ibm.com, anil.s.keshavamurthy@intel.com, davem@davemloft.net Subject: [patch 3/3] Text Edit Lock - kprobes i386 Content-Disposition: inline; filename=text-edit-lock-kprobes-i386.patch X-Poly-FromMTA: (dijkstra.casi.polymtl.ca [132.207.72.10]) at Tue, 3 Jul 2007 16:40:33 +0000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Kprobes can use the text edit lock to insure mutual exclusion when edition the code and make sure the pages are writable. Signed-off-by: Mathieu Desnoyers CC: prasanna@in.ibm.com CC: ananth@in.ibm.com CC: anil.s.keshavamurthy@intel.com CC: davem@davemloft.net --- arch/i386/kernel/kprobes.c | 30 ++++-------------------------- 1 file changed, 4 insertions(+), 26 deletions(-) Index: linux-2.6-lttng/arch/i386/kernel/kprobes.c =================================================================== --- linux-2.6-lttng.orig/arch/i386/kernel/kprobes.c 2007-06-29 14:15:38.000000000 -0400 +++ linux-2.6-lttng/arch/i386/kernel/kprobes.c 2007-06-29 14:25:08.000000000 -0400 @@ -169,42 +169,20 @@ void __kprobes arch_arm_kprobe(struct kprobe *p) { - unsigned long addr = (unsigned long) p->addr; - int page_readonly = 0; - - if (kernel_readonly_text(addr)) { - page_readonly = 1; - change_page_attr(virt_to_page(addr), 1, PAGE_KERNEL_RWX); - global_flush_tlb(); - } - + kernel_text_lock((unsigned long)p->addr, sizeof(kprobe_opcode_t)); *p->addr = BREAKPOINT_INSTRUCTION; + kernel_text_unlock((unsigned long)p->addr, sizeof(kprobe_opcode_t)); flush_icache_range((unsigned long) p->addr, (unsigned long) p->addr + sizeof(kprobe_opcode_t)); - - if (page_readonly) { - change_page_attr(virt_to_page(addr), 1, PAGE_KERNEL_RX); - global_flush_tlb(); - } } void __kprobes arch_disarm_kprobe(struct kprobe *p) { - unsigned long addr = (unsigned long) p->addr; - int page_readonly = 0; - - if (kernel_readonly_text(addr)) { - page_readonly = 1; - change_page_attr(virt_to_page(addr), 1, PAGE_KERNEL_RWX); - global_flush_tlb(); - } + kernel_text_lock((unsigned long)p->addr, sizeof(kprobe_opcode_t)); *p->addr = p->opcode; + kernel_text_unlock((unsigned long)p->addr, sizeof(kprobe_opcode_t)); flush_icache_range((unsigned long) p->addr, (unsigned long) p->addr + sizeof(kprobe_opcode_t)); - if (page_readonly) { - change_page_attr(virt_to_page(addr), 1, PAGE_KERNEL_RX); - global_flush_tlb(); - } } void __kprobes arch_remove_kprobe(struct kprobe *p) -- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68