From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754179AbbAWGnF (ORCPT ); Fri, 23 Jan 2015 01:43:05 -0500 Received: from mail7.hitachi.co.jp ([133.145.228.42]:37733 "EHLO mail7.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752120AbbAWGnC (ORCPT ); Fri, 23 Jan 2015 01:43:02 -0500 Subject: [PATCH -tip/urgent 2/2] [BUGFIX]kprobes: makes kprobes/enabled works correctly for optimized kprobes. From: Masami Hiramatsu To: Ingo Molnar Cc: tixy@linaro.org, Wang Nan , linux@arm.linux.org.uk, Linux Kernel Mailing List , lizefan@huawei.com, linux-arm-kernel@lists.infradead.org Date: Fri, 23 Jan 2015 15:42:31 +0900 Message-ID: <20150123064230.30731.29584.stgit@localhost.localdomain> In-Reply-To: <20150123064217.30731.49156.stgit@localhost.localdomain> References: <20150123064217.30731.49156.stgit@localhost.localdomain> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wang Nan 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 Acked-by: Masami Hiramatsu --- 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; } }