From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751875AbaHTITv (ORCPT ); Wed, 20 Aug 2014 04:19:51 -0400 Received: from srv2.trombetti.net ([65.254.53.252]:2238 "EHLO server" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751292AbaHTITt (ORCPT ); Wed, 20 Aug 2014 04:19:49 -0400 Message-ID: <53F45A29.6060604@shiftmail.org> Date: Wed, 20 Aug 2014 10:19:53 +0200 From: Ethan Wilson User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: "linux-kernel@vger.kernel.org" Subject: (trying again) how to get kernel stack trace if process not blocked? Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello list, I know cat /proc/pid/stack shows the kernel call stack of a process, and this is so good, but it will show just 0xffffffffffffffff if the process is running in kernel space and not blocked (sleeping). It would be *very* useful to get the kernel stack trace for a running process, even if imprecise, or at least knowing the name of the kernel function executing now (top of the stack). Why is it not doable? I tried to disable CONFIG_SCHED_OMIT_FRAME_POINTER but it didn't allow to print the stack from /proc/pid/stack anyway. What is the benefit of disabling such kernel option (i.e. having the frame pointer)? I guessed that maybe with EIP from /proc/pid/stat it is possible to do something like that but I can't find much information on how to do that. Thanks for any information EW