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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 D75A0C46475 for ; Tue, 23 Oct 2018 20:09:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9B5612081B for ; Tue, 23 Oct 2018 20:09:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="S7/R4xHg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9B5612081B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.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 S1728854AbeJXEeV (ORCPT ); Wed, 24 Oct 2018 00:34:21 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:50664 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725266AbeJXEeV (ORCPT ); Wed, 24 Oct 2018 00:34:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=uRrb+NUmtnP6E0f6nIrzsekr5AEymAac0qlaOiDA3A4=; b=S7/R4xHgcfsxLMceIEU0jQtDo 88tpjPjsnFwCRjfn0Nj5WMiZXUPZUWlCCpqHkm0V29LQmp1od+re+n8sL7QuP8G2skPcoYxS4mUDi 8oPd6jtZY4iMJKku9wC7kS2JAqovceThf2co1kSnZ9UjYi5uOqGJLiBKj73ioGRD97wcNENZ3u/ht LeL2GNuVLT+IDRJNEpzXLlinvFOX0CkCw/jQOb9nwwwYPbjKuoDKVo6RP2K+nNI1d1gJsqFkvbBdz xeT8HQ85tmg/fY/Idg0hKA20Ehqb8LuKMxNK4+camP/00nTJpPXBEgHJcCvszDDEejIz0muKmjzP+ GoEbOFwSw==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gF2zT-0007OI-Cn; Tue, 23 Oct 2018 20:09:23 +0000 Date: Tue, 23 Oct 2018 13:09:23 -0700 From: Matthew Wilcox To: Shuah Khan Cc: Joel Fernandes , Michal Hocko , Uladzislau Rezki , Kees Cook , Andrew Morton , linux-mm@kvack.org, LKML , Thomas Garnier , Oleksiy Avramchenko , Steven Rostedt , Joel Fernandes , Thomas Gleixner , Ingo Molnar , Tejun Heo , maco@android.com Subject: Re: [RFC PATCH 0/2] improve vmalloc allocation Message-ID: <20181023200923.GB25444@bombadil.infradead.org> References: <20181019173538.590-1-urezki@gmail.com> <20181022125142.GD18839@dhcp22.suse.cz> <20181022165253.uphv3xzqivh44o3d@pc636> <20181023072306.GN18839@dhcp22.suse.cz> <20181023152640.GD20085@bombadil.infradead.org> <20181023170532.GW18839@dhcp22.suse.cz> <98842edb-d462-96b1-311f-27c6ebfc108a@kernel.org> <20181023193044.GA139403@joelaf.mtv.corp.google.com> <024af44a-77e1-1c61-c9b2-64ffbe4f7c49@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <024af44a-77e1-1c61-c9b2-64ffbe4f7c49@kernel.org> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 23, 2018 at 01:48:32PM -0600, Shuah Khan wrote: > On 10/23/2018 01:30 PM, Joel Fernandes wrote: > > On Tue, Oct 23, 2018 at 11:13:36AM -0600, Shuah Khan wrote: > >> I like this proposal. I think we will open up lot of test opportunities with > >> this approach. > >> > >> Maybe we can use this stress test as a pilot and see where it takes us. > > > > I am a bit worried that such an EXPORT_SYMBOL_KSELFTEST mechanism can be abused by > > out-of-tree module writers to call internal functionality. > > That is valid concern to consider before we go forward with the proposal. > > We could wrap EXPORT_SYMBOL_KSELFTEST this in an existing debug option. This could > be fine grained for each sub-system for its debug option. We do have a few of these > now This all seems far more complicated than my proposed solution.