From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BCD68C5ACCC for ; Thu, 18 Oct 2018 13:17:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E21B2145D for ; Thu, 18 Oct 2018 13:17:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E21B2145D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728137AbeJRVSK (ORCPT ); Thu, 18 Oct 2018 17:18:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:54082 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727403AbeJRVSK (ORCPT ); Thu, 18 Oct 2018 17:18:10 -0400 Received: from gandalf.local.home (cpe-66-24-56-78.stny.res.rr.com [66.24.56.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F210F2145D; Thu, 18 Oct 2018 13:17:07 +0000 (UTC) Date: Thu, 18 Oct 2018 09:17:06 -0400 From: Steven Rostedt To: Sai Prakash Ranjan Cc: Stephen Boyd , Bjorn Andersson , Andy Gross , David Brown , Jiri Slaby , Kees Cook , "Joel Fernandes (Google)" , Geliang Tang , Greg Kroah-Hartman , Pramod Gurav , linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Rajendra Nayak , Vivek Gautam , Sibi Sankar Subject: Re: Crash in msm serial on dragonboard with ftrace bootargs Message-ID: <20181018091706.62310b38@gandalf.local.home> In-Reply-To: <58d2474c-53cd-e6cb-2d25-db38d1a88da6@codeaurora.org> References: <1cae8f10-55f5-20ce-9105-30af6f88bd6e@codeaurora.org> <20181016112928.4b52afb5@gandalf.local.home> <8c2fb318-813d-81f1-1e2f-cdbc68353077@codeaurora.org> <20181016125721.236ada82@gandalf.local.home> <20181016134803.1b9260c1@gandalf.local.home> <472db11e-49a6-a1ee-e298-791ee1bbb10b@codeaurora.org> <20181016141610.639b9000@gandalf.local.home> <20181016144123.24c47b38@gandalf.local.home> <7781815e-cba2-9e36-db6d-268298747876@codeaurora.org> <20181016150328.3450d718@gandalf.local.home> <20181017223334.29ca2837@vmware.local.home> <58d2474c-53cd-e6cb-2d25-db38d1a88da6@codeaurora.org> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 18 Oct 2018 10:51:18 +0530 Sai Prakash Ranjan wrote: > > So something else is causing an issue besides just msm_read. > > > > Can you do an objdump -dr of the entire vmlinux binary and gzip it and > > post it somewhere. Not sure if it would be too big to email. You could > > try sending it to me privately. I'd like to see the binary that you are > > using. > > > > I have sent the objdump and dot config to you privately. Thanks. I don't see anything that pops out, but then again, my arm asm foo is very rusty (it has been literally decades since I did any arm asm). I wonder if it could simply be a timing issue? ffff0000086eb538 : ffff0000086eb538: a9be7bfd stp x29, x30, [sp,#-32]! ffff0000086eb53c: 910003fd mov x29, sp ffff0000086eb540: a90153f3 stp x19, x20, [sp,#16] ffff0000086eb544: aa0003f4 mov x20, x0 ffff0000086eb548: 2a0103f3 mov w19, w1 ffff0000086eb54c: aa1e03e0 mov x0, x30 ffff0000086eb550: 97e6bae4 bl ffff00000809a0e0 <_mcount> The above is changed to nop on boot, but then to: bl ftrace_caller When ftrace is enabled. ffff0000086eb554: 8b334280 add x0, x20, w19, uxtw ffff0000086eb558: b9400000 ldr w0, [x0] ffff0000086eb55c: a94153f3 ldp x19, x20, [sp,#16] ffff0000086eb560: a8c27bfd ldp x29, x30, [sp],#32 ffff0000086eb564: d65f03c0 ret ffff00000809a0e4 : ffff00000809a0e4: a9bf7bfd stp x29, x30, [sp,#-16]! ffff00000809a0e8: 910003fd mov x29, sp ffff00000809a0ec: d10013c0 sub x0, x30, #0x4 ffff00000809a0f0: f94003a1 ldr x1, [x29] ffff00000809a0f4: f9400421 ldr x1, [x1,#8] ffff00000809a0f8: d1001021 sub x1, x1, #0x4 ffff00000809a0fc : ffff00000809a0fc: d503201f nop The above nop gets patched to: bl ftrace_ops_no_ops Which will iterate through all the registered functions. ffff00000809a100 : ffff00000809a100: d503201f nop The above only gets set when function graph tracer is enabled, which it is not in this case. ffff00000809a104: a8c17bfd ldp x29, x30, [sp],#16 ffff00000809a108: d65f03c0 ret Anyone see any problems here? -- Steve