From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751811AbbATC63 (ORCPT ); Mon, 19 Jan 2015 21:58:29 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:65005 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751410AbbATC62 (ORCPT ); Mon, 19 Jan 2015 21:58:28 -0500 From: Wang Nan To: CC: , , , , Subject: [PATCH] kprobes: bugfix: makes kprobes/enabled works correctly for optimized kprobes. Date: Tue, 20 Jan 2015 10:51:51 +0800 Message-ID: <1421722311-30455-1-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.4 In-Reply-To: <54BCFC6E.1080007@hitachi.com> References: <54BCFC6E.1080007@hitachi.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.247] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org debugfs/kprobes/enabled doesn't work correctly on optimized kprobes. Masami Hiramatsu has a test report on x86_64 platform: https://lkml.org/lkml/2015/1/19/274 This patch forces it to unoptimize kprobe if kprobes_all_disarmed is set. It also checks the flag in unregistering path for skipping unneeded disarming process when kprobes globally disarmed. Signed-off-by: Wang Nan --- kernel/kprobes.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 9471710..fb995ef 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -869,7 +869,8 @@ static void __disarm_kprobe(struct kprobe *p, bool reopt) { struct kprobe *_p; - unoptimize_kprobe(p, false); /* Try to unoptimize */ + /* Try to unoptimize */ + unoptimize_kprobe(p, kprobes_all_disarmed); if (!kprobe_queued(p)) { arch_disarm_kprobe(p); @@ -1571,7 +1572,13 @@ static struct kprobe *__disable_kprobe(struct kprobe *p) /* Try to disarm and disable this/parent probe */ if (p == orig_p || aggr_kprobe_disabled(orig_p)) { - disarm_kprobe(orig_p, true); + /* + * If kprobes_all_disarmed is set, orig_p + * should have already been disarmed, so + * skip unneed disarming process. + */ + if (!kprobes_all_disarmed) + disarm_kprobe(orig_p, true); orig_p->flags |= KPROBE_FLAG_DISABLED; } } -- 1.8.4