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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 9112CC7618B for ; Thu, 25 Jul 2019 17:07:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6575E2238C for ; Thu, 25 Jul 2019 17:07:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388580AbfGYRH0 (ORCPT ); Thu, 25 Jul 2019 13:07:26 -0400 Received: from foss.arm.com ([217.140.110.172]:33132 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387923AbfGYRHZ (ORCPT ); Thu, 25 Jul 2019 13:07:25 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5C96A174E; Thu, 25 Jul 2019 10:07:25 -0700 (PDT) Received: from arrakis.emea.arm.com (arrakis.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3EFD23F71A; Thu, 25 Jul 2019 10:07:23 -0700 (PDT) Date: Thu, 25 Jul 2019 18:07:21 +0100 From: Catalin Marinas To: Anshuman Khandual Cc: linux-mm@kvack.org, Mark Rutland , x86@kernel.org, Kees Cook , Sri Krishna chowdary , Tetsuo Handa , Ard Biesheuvel , Dave Hansen , linux-kernel@vger.kernel.org, Matthew Wilcox , Michal Hocko , Masahiro Yamada , Mark Brown , Andrew Morton , Steven Price , linux-arm-kernel@lists.infradead.org Subject: Re: [RFC] mm/pgtable/debug: Add test validating architecture page table helpers Message-ID: <20190725170720.GB11545@arrakis.emea.arm.com> References: <1564037723-26676-1-git-send-email-anshuman.khandual@arm.com> <1564037723-26676-2-git-send-email-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1564037723-26676-2-git-send-email-anshuman.khandual@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 25, 2019 at 12:25:23PM +0530, Anshuman Khandual wrote: > +#if !defined(__PAGETABLE_PMD_FOLDED) && !defined(__ARCH_HAS_4LEVEL_HACK) > +static void pud_clear_tests(void) > +{ > + pud_t pud; > + > + pud_clear(&pud); > + WARN_ON(!pud_none(pud)); > +} For the clear tests, I think you should initialise the local variable to something non-zero rather than rely on whatever was on the stack. In case it fails, you have a more deterministic behaviour. -- Catalin 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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 E8EE6C7618B for ; Thu, 25 Jul 2019 17:07:36 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B77872238C for ; Thu, 25 Jul 2019 17:07:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="QZmbGLwr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B77872238C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=kkFR4IB5CQjsq0YybnCsOvuPq0cUgBYZtUZwZ1BEBfo=; b=QZmbGLwrxwRXYd aYIohIqw3U+Y1SVM1yxKFEfvZHTH4hJvCQsSsxH2FiKEVtCWh3wjfLFm35hgLnHtz33Vzjb4lRavG x9//pwDXoOT+2lhRcIIau/MZgtKUcodV38bQkRsYdGTzDyJRHw7QgY+qBbSw2/uj20ge0orRQvM6p mGYb8U2dT4zXGCWIM8M88ZY/dmp2abXRpXxSZcC/Way9sxmfidnLNSSnpEQepDvzmUH2OVexw+szC clvsNl5krn/s7phNvoLisCagzvg0L/IiY7xvy5cZaciTvh3p/sjn7bDY3LdbIfOPLMdduje1CV770 iicWZ5LtwmS9XMpnqHPQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hqhDF-0000I5-Aa; Thu, 25 Jul 2019 17:07:29 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hqhDC-0000HG-1T for linux-arm-kernel@lists.infradead.org; Thu, 25 Jul 2019 17:07:27 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5C96A174E; Thu, 25 Jul 2019 10:07:25 -0700 (PDT) Received: from arrakis.emea.arm.com (arrakis.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3EFD23F71A; Thu, 25 Jul 2019 10:07:23 -0700 (PDT) Date: Thu, 25 Jul 2019 18:07:21 +0100 From: Catalin Marinas To: Anshuman Khandual Subject: Re: [RFC] mm/pgtable/debug: Add test validating architecture page table helpers Message-ID: <20190725170720.GB11545@arrakis.emea.arm.com> References: <1564037723-26676-1-git-send-email-anshuman.khandual@arm.com> <1564037723-26676-2-git-send-email-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1564037723-26676-2-git-send-email-anshuman.khandual@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190725_100726_136467_9BC93533 X-CRM114-Status: UNSURE ( 9.28 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kees Cook , Sri Krishna chowdary , Ard Biesheuvel , Tetsuo Handa , x86@kernel.org, Dave Hansen , linux-kernel@vger.kernel.org, Matthew Wilcox , Michal Hocko , linux-mm@kvack.org, Masahiro Yamada , Mark Brown , Andrew Morton , Steven Price , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Jul 25, 2019 at 12:25:23PM +0530, Anshuman Khandual wrote: > +#if !defined(__PAGETABLE_PMD_FOLDED) && !defined(__ARCH_HAS_4LEVEL_HACK) > +static void pud_clear_tests(void) > +{ > + pud_t pud; > + > + pud_clear(&pud); > + WARN_ON(!pud_none(pud)); > +} For the clear tests, I think you should initialise the local variable to something non-zero rather than rely on whatever was on the stack. In case it fails, you have a more deterministic behaviour. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel