From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f198.google.com (mail-lb0-f198.google.com [209.85.217.198]) by kanga.kvack.org (Postfix) with ESMTP id 4A8226B0005 for ; Fri, 20 May 2016 02:48:27 -0400 (EDT) Received: by mail-lb0-f198.google.com with SMTP id ga2so42064518lbc.0 for ; Thu, 19 May 2016 23:48:27 -0700 (PDT) Received: from mail-wm0-x243.google.com (mail-wm0-x243.google.com. [2a00:1450:400c:c09::243]) by mx.google.com with ESMTPS id b199si2900888wme.74.2016.05.19.23.48.25 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 19 May 2016 23:48:25 -0700 (PDT) Received: by mail-wm0-x243.google.com with SMTP id n129so26603401wmn.1 for ; Thu, 19 May 2016 23:48:25 -0700 (PDT) Date: Fri, 20 May 2016 08:48:20 +0200 From: Ingo Molnar Subject: Re: [PATCHv9 2/2] selftest/x86: add mremap vdso test Message-ID: <20160520064820.GB29418@gmail.com> References: <1463487232-4377-1-git-send-email-dsafonov@virtuozzo.com> <1463487232-4377-3-git-send-email-dsafonov@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1463487232-4377-3-git-send-email-dsafonov@virtuozzo.com> Sender: owner-linux-mm@kvack.org List-ID: To: Dmitry Safonov Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, luto@amacapital.net, tglx@linutronix.de, hpa@zytor.com, x86@kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org, 0x7f454c46@gmail.com, Shuah Khan , linux-kselftest@vger.kernel.org * Dmitry Safonov wrote: > Should print on success: > [root@localhost ~]# ./test_mremap_vdso_32 > AT_SYSINFO_EHDR is 0xf773f000 > [NOTE] Moving vDSO: [f773f000, f7740000] -> [a000000, a001000] > [OK] > Or segfault if landing was bad (before patches): > [root@localhost ~]# ./test_mremap_vdso_32 > AT_SYSINFO_EHDR is 0xf774f000 > [NOTE] Moving vDSO: [f774f000, f7750000] -> [a000000, a001000] > Segmentation fault (core dumped) So I still think that generating potential segfaults is not a proper way to test a new feature. How are we supposed to tell the feature still works? I realize that glibc is a problem here - but that doesn't really change the QA equation: we are adding new kernel code to help essentially a single application out of tens of thousands of applications. At minimum we should have a robust testcase ... Thanks, Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org