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=-0.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 2AE6EC432C0 for ; Thu, 28 Nov 2019 13:48:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 641B52176D for ; Thu, 28 Nov 2019 13:48:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=goldelico.com header.i=@goldelico.com header.b="KWmWJv+U" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726700AbfK1Ns5 (ORCPT ); Thu, 28 Nov 2019 08:48:57 -0500 Received: from mo4-p01-ob.smtp.rzone.de ([85.215.255.51]:33431 "EHLO mo4-p01-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726227AbfK1Ns4 (ORCPT ); Thu, 28 Nov 2019 08:48:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1574948934; s=strato-dkim-0002; d=goldelico.com; h=To:References:Message-Id:Cc:Date:In-Reply-To:From:Subject: X-RZG-CLASS-ID:X-RZG-AUTH:From:Subject:Sender; bh=/wIFaKm+ebxmf1zDi6heRwAyFXGyk1wVGBocTvOmgvg=; b=KWmWJv+UuVCytxbtt7bbmW7qKStQeCk4zD7XVhLzCqDb3hwTytpgEmQyNi2Q9zUqLx aHYNgAfouQOGcYDbM3WDIT/BO5VzcvBfQ9oV2J3gRhjkCpZzaeASLetkzld7DTLdVnU3 VlOqYjSnt84aH5xLZ9eQulQeV3fXY1NmG44oZChAY9smnzj/5Zf5Zox4luS2SOKgOtp4 q9+732esAeoKqI2PEfQxcwnT0s2ArjODDqUwfAKRHxA07QTG+rteBEhkKinxTHj3lFO3 FcHKfXX8r9TVijF2Tklh1au0VHoan7ujIrWOTO1LNu50DsYR8pN/Y1TsIUzh6t97yFyk 5BPg== X-RZG-AUTH: ":JGIXVUS7cutRB/49FwqZ7WcJeFKiMgPgp8VKxflSZ1P34KBj4Qpw9iZeHmAiw43upSE=" X-RZG-CLASS-ID: mo00 Received: from imac.fritz.box by smtp.strato.de (RZmta 45.0.2 DYNA|AUTH) with ESMTPSA id y07703vASDmkKBI (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (curve X9_62_prime256v1 with 256 ECDH bits, eq. 3072 bits RSA)) (Client did not present a certificate); Thu, 28 Nov 2019 14:48:46 +0100 (CET) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: MIPS: bug: gettimeofday syscall broken on CI20 board From: "H. Nikolaus Schaller" In-Reply-To: <4807842.gtHLO0kk0V@hyperion> Date: Thu, 28 Nov 2019 14:48:46 +0100 Cc: mips-creator-ci20-dev@googlegroups.com, Vincenzo Frascino , Ralf Baechle , Paul Burton , linux-mips@vger.kernel.org, Linux Kernel Mailing List , Discussions about the Letux Kernel Content-Transfer-Encoding: 7bit Message-Id: <01D75E67-EC2E-4C74-B9BB-752773C481A9@goldelico.com> References: <18788C50-F29B-4BD7-89F6-B056FF490214@goldelico.com> <7b6275c7-ab2b-a647-6bf7-d5e1c4523c98@arm.com> <4807842.gtHLO0kk0V@hyperion> To: Maarten ter Huurne X-Mailer: Apple Mail (2.3124) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org > Am 28.11.2019 um 14:29 schrieb Maarten ter Huurne : > > On Thursday, 28 November 2019 13:33:17 CET H. Nikolaus Schaller wrote: >> Hi Vincenzo, >> >>> Am 28.11.2019 um 13:21 schrieb Vincenzo Frascino >>> :> >>> [...] >>> The the lib that provides the gettimeofday() changes accordingly >>> with vdso_data. 5.4 and 4.19 have 2 different vdso libraries as >>> well. >> >> Yes, that is what I have assumed what happens. How do these libs go >> into an existing and working root-file-system with Debian Stretch? > > I'm a novice when it comes to vDSO, so someone please correct me if I'm > wrong. > > From what I read vDSO is a library in the sense that it exports ELF > symbols that applications and other libraries (libc in particular) can > use, but it is not a file on disk. Ah, ok. This would mean that the libc providing the gettimeofday() should be able to find out a modified changed vdso_data format by inspecting these ELF symbols. > > As such, which rootfs you use shouldn't matter, since the vDSO is not in > the rootfs. Instead, it is contained in the kernel image. Searching for > "linux-vdso.so.1" on packages.debian.org indeed returns no hits. > > There is a check in arch/mips/vdso/Makefile that disables vDSO on MIPS > when building the kernel with binutils < 2.25. I don't know if that is > in any way related to this issue. What still does not fit into the picture is the errno = 1 i.e. EPERM. Maybe I have to study the libc code that tries to read the ELF symbols you have mentioned. It may fail for unknown reasons. BR and thanks, Nikolaus