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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 ED5DEC76186 for ; Wed, 24 Jul 2019 19:32:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BF0D820659 for ; Wed, 24 Jul 2019 19:32:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="daangUid" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388677AbfGXTcj (ORCPT ); Wed, 24 Jul 2019 15:32:39 -0400 Received: from mail-ed1-f66.google.com ([209.85.208.66]:44232 "EHLO mail-ed1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388653AbfGXTca (ORCPT ); Wed, 24 Jul 2019 15:32:30 -0400 Received: by mail-ed1-f66.google.com with SMTP id k8so48068790edr.11; Wed, 24 Jul 2019 12:32:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=RmmUOfw6KdNJB7Dw3A649BONg+TVcJuxBPKeIVpSw5Y=; b=daangUidITkUVKr7vk3OUx08Gl1Jxg57OGBaW32/VfgcDYW4r8ueSaHlvl7prjeAAn 6hbbOLWpvFqcVTCDWVzqtuonDNxTeBQ+SKsmAZa2QZG5GqbYinzXg9AQ78AarKMfpjje 3IQG9AXksuIrunc2zx7/mlH6K0s4IGMvmxff7cHuLu5R8mGFv5U79S7o+KLdAHgA95Lr uN4yR1koyNq/sBo4AzrOFlpzNT0eZeoXLnzT7iCkJWsONrShxQpzSGGp7Us4+8mQ1sNf vIPKBtPZPxJUw3XWCA/roIuHPsq7vBfCJS3fZ69Vvb6pSNJKIcsFkES1O2U9mLRunOvz kkDA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=RmmUOfw6KdNJB7Dw3A649BONg+TVcJuxBPKeIVpSw5Y=; b=B4FhwRlMmV/HpR7cZinVEBhsvjD7k9K/ZAnnBZsHwvc4k1+25q0Tp8go0N/2+Ro9QF 4NR0BOThx/E1dBHcoKPo8tR8jC4UwCKDUXk2TgVd5RqeIhJOqBMcAzNGwWYkDvWeAayM T/AJexE2DddYjmZosyXTCqSzv8aEGbG1l89zbzSUsG0H5+CzOHr5J9cMvpwKNsZKsA/6 6Fa4gRbyBFWFF2SxkUniErUzCjtO/N6rc7EO4JqpaES8yd0UJ/Qy3Wya9CBMKMCicCzK RqtU1C9QVmC94qQiz5xjkA2phmS54hmihEyaDX7YCA6PAXDvdyoo2xbMSI20OZFfA94C M4mQ== X-Gm-Message-State: APjAAAVuS75jfJ6mrzh9hwmBsrRYva0WJctAsuKGboqkmMME3U0eMV6I 3dPpVvusT3V3B4PnUj6Ia9UdwddUYBGgdhVytFmNeyHlnAw= X-Google-Smtp-Source: APXvYqzQK3O5v+7yVlFJSGeU4C2I4d4sf8cRDv+2qxowZgzIVi2SvDX7ph8dKH/Lo5xszlodW3vLefHeISTmBsyrRKY= X-Received: by 2002:a17:906:7f16:: with SMTP id d22mr64449323ejr.17.1563996748713; Wed, 24 Jul 2019 12:32:28 -0700 (PDT) MIME-Version: 1.0 References: <20190625143715.1689-1-hch@lst.de> <20190625143715.1689-10-hch@lst.de> <20190717215956.GA30369@altlinux.org> <20190718.141405.1070121094691581998.davem@davemloft.net> In-Reply-To: <20190718.141405.1070121094691581998.davem@davemloft.net> From: Anatoly Pugachev Date: Wed, 24 Jul 2019 22:32:17 +0300 Message-ID: Subject: Re: [PATCH 09/16] sparc64: use the generic get_user_pages_fast code To: David Miller Cc: "Dmitry V. Levin" , Christoph Hellwig , khalid.aziz@oracle.com, torvalds@linux-foundation.org, akpm@linux-foundation.org, Sparc kernel list , linux-mm@kvack.org, Linux Kernel list Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 19, 2019 at 12:14 AM David Miller wrote: > > So this ended up as commit 7b9afb86b6328f10dc2cad9223d7def12d60e505 > > (thanks to Anatoly for bisecting) and introduced a regression: > > futex.test from the strace test suite now causes an Oops on sparc64 > > in futex syscall. > > > > Here is a heavily stripped down reproducer: > > Does not reproduce for me on a T4-2 machine. > > So this problem might depend on the type of system you are on, > I suspect it's one of those "pre-Niagara vs. Niagara and later" > situations because that's the dividing line between two set of > wildly different TLB and cache management methods. > > What kind of machine are you on? David, the first test where it was discovered was done on my test LDOM named ttip, hardware (hypervisor) is T5-2 server, running under Solaris 11.4 OS. ttip LDOM is debian sparc64 unstable , so with almost all the latest software (gcc 8.3.0, binutils 2.32.51.20190707-1, debian GLIBC 2.28-10, etc..) For another test, i also installed LDOM with oracle sparc linux https://oss.oracle.com/projects/linux-sparc/ , but I've to install a more fresh version of gcc on it first, since system installed gcc 4.4 is too old for a git kernel (linux-2.6/Documentation/Changes lists gcc 4.6 as a minimal version), so I choose to install gcc-7.4.0 to /opt/ (leaving system installed gcc 4.4 under /usr/bin). Compiled and installed git kernel version, i.e. last tag 5.3.0-rc1 and ran the test. Kernel still produced oops.