From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933338Ab0HEMfQ (ORCPT ); Thu, 5 Aug 2010 08:35:16 -0400 Received: from mail7.hitachi.co.jp ([133.145.228.42]:40318 "EHLO mail7.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933193Ab0HEMfM (ORCPT ); Thu, 5 Aug 2010 08:35:12 -0400 X-AuditID: b753bd60-a98ddba000000a18-f7-4c5aaffecc9f Message-ID: <4C5AAFF9.4030103@hitachi.com> Date: Thu, 05 Aug 2010 21:35:05 +0900 From: Masami Hiramatsu Organization: Systems Development Lab., Hitachi, Ltd., Japan User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 Cc: Masami Hiramatsu , Ananth N Mavinakayanahalli , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org Subject: [PATCH 1/2] kprobes: Update document about irq disabled state in kprobe handler Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== X-FMFTCR: RANGEC To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Update kprobes.txt about interrupts disabled state inside kprobes handlers, because optimized probe/boosted kretprobe run without disabling interrrupts on x86. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: linux-kernel@vger.kernel.org Cc: linux-doc@vger.kernel.org --- Documentation/kprobes.txt | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt index 6653017..4189f01 100644 --- a/Documentation/kprobes.txt +++ b/Documentation/kprobes.txt @@ -541,9 +541,11 @@ Kprobes does not use mutexes or allocate memory except during registration and unregistration. Probe handlers are run with preemption disabled. Depending on the -architecture, handlers may also run with interrupts disabled. In any -case, your handler should not yield the CPU (e.g., by attempting to -acquire a semaphore). +architecture and optimization state, handlers may also run with +interrupts disabled (e.g., kretprobe handlers and optimized kprobe +handlers run without interrupt disabled on x86/x86-64). In any case, +your handler should not yield the CPU (e.g., by attempting to acquire +a semaphore). Since a return probe is implemented by replacing the return address with the trampoline's address, stack backtraces and calls