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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 9C796C54FCE for ; Mon, 23 Mar 2020 15:55:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6AC8920722 for ; Mon, 23 Mar 2020 15:55:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="DcupFgfR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727202AbgCWPy7 (ORCPT ); Mon, 23 Mar 2020 11:54:59 -0400 Received: from us-smtp-delivery-74.mimecast.com ([216.205.24.74]:21838 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727207AbgCWPy7 (ORCPT ); Mon, 23 Mar 2020 11:54:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584978898; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=aONbZkW7VTtlNQ7IX/OP6HCvxPbDTjsQv8h6JUzUnHw=; b=DcupFgfRD/LTA1e5rN6ma/k+cmMcZNVu9B3iwubyfX2QYPS0gJPH2ivaCgV+FxjXEUZNOM ibBSXqpaxa69SWBGNnJAwAMKRqg3Z2IQVPcWfjkZCleJD9CSJOzA0HNu3lfE5qS//Sto75 rHM5a/Qjed83xCfixnZpCTpttGTJQRE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-285-8D5ohllOMACo1HLXscfZ1Q-1; Mon, 23 Mar 2020 11:54:56 -0400 X-MC-Unique: 8D5ohllOMACo1HLXscfZ1Q-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D86F6800D54; Mon, 23 Mar 2020 15:54:54 +0000 (UTC) Received: from optiplex-lnx (unknown [10.33.36.220]) by smtp.corp.redhat.com (Postfix) with ESMTPS id F1CC919C4F; Mon, 23 Mar 2020 15:54:52 +0000 (UTC) Date: Mon, 23 Mar 2020 11:54:49 -0400 From: Rafael Aquini To: Michal Hocko Cc: Shakeel Butt , Andrew Morton , LKML , linux-kselftest@vger.kernel.org, shuah@kernel.org Subject: Re: [PATCH] tools/testing/selftests/vm/mlock2-tests: fix mlock2 false-negative errors Message-ID: <20200323155449.GG23364@optiplex-lnx> References: <20200322020326.GB1068248@t490s> <20200321213142.597e23af955de653fc4db7a1@linux-foundation.org> <20200323075208.GC7524@dhcp22.suse.cz> <20200323144240.GB23364@optiplex-lnx> <20200323145106.GM7524@dhcp22.suse.cz> <20200323150259.GD23364@optiplex-lnx> <20200323151256.GP7524@dhcp22.suse.cz> <20200323154159.GF23364@optiplex-lnx> <20200323155111.GQ7524@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200323155111.GQ7524@dhcp22.suse.cz> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On Mon, Mar 23, 2020 at 04:51:11PM +0100, Michal Hocko wrote: > On Mon 23-03-20 11:41:59, Rafael Aquini wrote: > > On Mon, Mar 23, 2020 at 04:12:56PM +0100, Michal Hocko wrote: > > > On Mon 23-03-20 11:02:59, Rafael Aquini wrote: > [...] > > > > The selftest also checks the kernel visible effect, via > > > > /proc/kpageflags, and that's where it fails after 9c4e6b1a7027f. > > > > > > I really fail to see your point. Even if you are right that the self > > > test is somehow evaluating the kernel implementation which I am not sure > > > is the scope of the selft thest but anyway. The mere fact that the > > > kernel test fails on a perfectly valid change should just suggest that > > > the test is leading to false positives and therefore should be fixed. > > > Your proposed fix is simply suboptimal because it relies on yet another > > > side effect which might change anytime in the future and still lead to a > > > correctly behaving kernel. See my point? > > > > > > > OK, I concede your point on the bogusness of checking the page flags in > > this particular test and expect certain valuse there, given that no other > > selftest seems to be doing that level of inner kenrel detail scrutiny. > > > > I'll repost this fix suggestion getting rif of those related > > checkpoints. > > Here is what I have after I had to context switch to something else > before finishing it. Feel free to reuse if you feel like. It is likely > to not even compile. > I'm OK with it, if you want to go ahead and do the kill. Thanks -- Rafael