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 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 22A4CC433F5 for ; Thu, 30 Aug 2018 15:51:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C517C20645 for ; Thu, 30 Aug 2018 15:50:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C517C20645 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 S1727553AbeH3Txp (ORCPT ); Thu, 30 Aug 2018 15:53:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:36490 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727229AbeH3Txp (ORCPT ); Thu, 30 Aug 2018 15:53:45 -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 7A4C320645; Thu, 30 Aug 2018 15:50:57 +0000 (UTC) Date: Thu, 30 Aug 2018 11:50:55 -0400 From: Steven Rostedt To: Masami Hiramatsu Cc: Shuah Khan , Ingo Molnar , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 22/32] selftests/ftrace: Add ringbuffer size changing testcase Message-ID: <20180830115055.6a28054c@gandalf.local.home> In-Reply-To: <20180830161218.e46affa5a84abd47c9cf2a39@kernel.org> References: <153443695002.23257.13628220023468200991.stgit@devbox> <153443757416.23257.9284862385646039929.stgit@devbox> <20180824191836.305ad740@gandalf.local.home> <20180830161218.e46affa5a84abd47c9cf2a39@kernel.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, 30 Aug 2018 16:12:18 +0900 Masami Hiramatsu wrote: > > I'm fine with this, but one day I need to port over some of my other > > tests. I have a test that stresses the ring buffer size (basically > > checks to see if it can cause an oom). I need to port that to > > selftests. But for now... > > Hmm, such stress test is not good for kselftest, since it can cause > oom and kill some test process. Maybe we should have such stresstest > framework (which allows test to crash kernel) The point of the test is to make sure that it doesn't kill everything :-) The ring buffer code is suppose to detect that it will cause an OOM, and if it does that's considered a failure. Just like any other test, if it fails, it can crash the kernel. But the ring buffer code is suppose to be able to keep the kernel from crashing (including triggering OOM) if the buffer size is stressed. Maybe I'll port that over today :-/ -- Steve