Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754085AbYKKVAP (ORCPT ); Tue, 11 Nov 2008 16:00:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752957AbYKKU6Y (ORCPT ); Tue, 11 Nov 2008 15:58:24 -0500 Received: from mx2.redhat.com ([66.187.237.31]:39848 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753889AbYKKU6X (ORCPT ); Tue, 11 Nov 2008 15:58:23 -0500 Message-ID: <4919F1C6.4030106@redhat.com> Date: Tue, 11 Nov 2008 15:57:42 -0500 From: Masami Hiramatsu User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Andrew Morton CC: Ananth N Mavinakayanahalli , Jim Keniston , David Miller , LKML , systemtap-ml , Rusty Russell Subject: [PATCH 7/7] kprobes: Support probing module __init function X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2491 Lines: 75 Allow kprobes to probe module __init routines. When __init functions are freed, kprobes which probe those functions are set to "Gone" flag. These "Gone" probes are disarmed from the code and never be enabled. Signed-off-by: Masami Hiramatsu --- kernel/kprobes.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) Index: 2.6.28-rc4/kernel/kprobes.c =================================================================== --- 2.6.28-rc4.orig/kernel/kprobes.c +++ 2.6.28-rc4/kernel/kprobes.c @@ -676,6 +676,16 @@ int __kprobes register_kprobe(struct kpr preempt_enable(); return -EINVAL; } + /* + * If the module freed .init.text, we couldn't insert + * kprobes in there. + */ + if (within_module_init((unsigned long)p->addr, probed_mod) && + probed_mod->state != MODULE_STATE_COMING) { + module_put(probed_mod); + preempt_enable(); + return -EINVAL; + } } preempt_enable(); @@ -1072,19 +1082,24 @@ static int __kprobes kprobes_module_call struct hlist_node *node; struct kprobe *p; unsigned int i; + int checkcore = (val == MODULE_STATE_GOING); - if (val != MODULE_STATE_GOING) + if (val != MODULE_STATE_GOING && val != MODULE_STATE_LIVE) return NOTIFY_DONE; /* - * module .text section will be freed. We need to - * disable kprobes which have been inserted in the section. + * When MODULE_STATE_GOING was notified, both of module .text and + * .init.text sections would be freed. When MODULE_STATE_LIVE was + * notified, only .init.text section would be freed. We need to + * disable kprobes which have been inserted in the sections. */ mutex_lock(&kprobe_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry_rcu(p, node, head, hlist) - if (within_module_core((unsigned long)p->addr, mod)) { + if (within_module_init((unsigned long)p->addr, mod) || + (checkcore && + within_module_core((unsigned long)p->addr, mod))) { /* * The vaddr this probe is installed will soon * be vfreed buy not synced to disk. Hence, -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America) Inc. Software Solutions Division e-mail: mhiramat@redhat.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/