From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 26067 invoked by alias); 24 Mar 2018 17:43:41 -0000 Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org Received: (qmail 26055 invoked by uid 89); 24 Mar 2018 17:43:40 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.6 required=5.0 tests=BAYES_00,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=no version=3.3.2 spammy=Kirk, kirk, traces, H*c:alternative X-HELO: mail-oi0-f50.google.com Received: from mail-oi0-f50.google.com (HELO mail-oi0-f50.google.com) (209.85.218.50) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Sat, 24 Mar 2018 17:43:39 +0000 Received: by mail-oi0-f50.google.com with SMTP id 126-v6so6909642oig.0 for ; Sat, 24 Mar 2018 10:43:39 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=GL3ViQalBJec2wdxI+BF+NZ29/OdSN78iOES4d9smAg=; b=QlcM38OKi4mSXZ+6OKm+rnBoT9dpiPaWQdFo0UiSmKV3iaZN2pZV56lqT76jb4CA1R glq8IRYEbrcXa2bgpzKBAqGR3PXqHyTZr1RouAYyTM561usrxMsxKGvWpMqVm5wbiVRq y8Bak+a1dDN10a5EuRRf/kfk37T5r7E47sRKPl42mgQVjlPBZvkyBtnuZ/qNpBpusEx2 azmiZxm+WV7t5veimtXnIlCNmVSNqcEXeYkQFxJec8FX+rf1/FJrsD31Aq5O/BFOSdn1 d5h1HEIR4ufGQu5zSMVY7cgRiUoVp6/ZAPjjmUPvVO1yJjwrpO+lvEthrEx7M0d5Ckaf 8z9g== X-Gm-Message-State: AElRT7HZKYmPImQTAdM24cCC1yrNl33EWPeNyRa/RxKou0/DtpKdimrZ AgcNN67n5rhTTE3ezq2VLPxihKxxJJSPSOr3eec= X-Google-Smtp-Source: AG47ELsmpgC+EzAiGkehvjZ73/2CJEm5VxtLg2epI9VVLH6t0n51Me93nOQWVni9vV8NF9OvQfAL7yB2IFzY1Lj8oD4= X-Received: by 10.202.43.22 with SMTP id i22mr5684540oik.157.1521913417459; Sat, 24 Mar 2018 10:43:37 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a9d:3e04:0:0:0:0:0 with HTTP; Sat, 24 Mar 2018 10:43:37 -0700 (PDT) In-Reply-To: References: From: Phil Kirk Date: Sat, 24 Mar 2018 17:43:00 -0000 Message-ID: Subject: Re: systemtap on 4.16 kernel - stack unwinding problems To: systemtap@sourceware.org Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2018-q1/txt/msg00106.txt.bz2 i've tried re-building with gcc-7 (7.2.0) but stack unwinding still fails with CONFIG_RANDOMIZE_BASE set. for now i'll just build without it so i can get the stack traces i want. thanks phil On Fri, Mar 23, 2018 at 11:04 PM, Phil Kirk wrote: > hi, > > i've been trying to use systemtap against a freshly built 4.16 kernel, > systemtap was also freshly built, but having problems with stack unwinding, > as an example, when running: > > stap -e 'probe kernel.function("invalidate_mapping_pages") > {printf("stack:%s\n", print_backtrace());}' > > i was only getting the top stack frame. when tracing inside the ip stack i > was getting the same results. after asking on irc i rebuilt my kernel > without CONFIG_RANDOMIZE_BASE set to y and now i get a more complete stack > trace, i need to try and verify if the stack i'm getting when tracing > invalidate_mapping_pages is accurate but for tracing in the ip stack it > looks much better. > > the kernel was built using gcc 5.4.0, i'll try using a more up to date gcc > tomorrow. > > phil >