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=-4.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 8FA43C433DF for ; Fri, 31 Jul 2020 20:32:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 63F54208E4 for ; Fri, 31 Jul 2020 20:32:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596227538; bh=408Q0Hh+fgrrPI7C/uxjoUhChUZT+B18EfDwFr/6pIQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=IhbvPIdpw009rj3rCaTbRnhjnY/bm222Bif695mVem3SSjIl/E7dapl3ujxuuwbwn osJdVg2ZM6bHLGWKD/ChrkkYmZTKYC6zUnaOrt9fmzkm+iGuhIVAyp43oO089pS7Jr zrRIDG8bCfk7UyhWz+c2UIkZj7aLfruRTh5oPJlc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728917AbgGaUcR (ORCPT ); Fri, 31 Jul 2020 16:32:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:54326 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726950AbgGaUcQ (ORCPT ); Fri, 31 Jul 2020 16:32:16 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 096772087C; Fri, 31 Jul 2020 20:32:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596227536; bh=408Q0Hh+fgrrPI7C/uxjoUhChUZT+B18EfDwFr/6pIQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=UN+EYyNBTAK7YK11SGuSdNTJr8UDBGjCxmVTjvaRi93u/RLGBcPhn/GTxvCs2RN+5 do5QXszzBuQunW/zfSEX0rog61dmQmIl1o4Lame7kXp+gbvN1CwV5x+CnLTLh5XhAd 0qJwccZ5fjOXm5IeU9B7vRPlH2PD8cgCa7r0cxJs= Date: Fri, 31 Jul 2020 13:32:15 -0700 From: Andrew Morton To: Matthew Wilcox Cc: qiang.zhang@windriver.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/dmapool.c: add WARN_ON() in dma_pool_destroy Message-Id: <20200731133215.73cf5ce464e2b894aeac0773@linux-foundation.org> In-Reply-To: <20200731023858.GO23808@casper.infradead.org> References: <20200731023939.19206-1-qiang.zhang@windriver.com> <20200731023858.GO23808@casper.infradead.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; 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 Fri, 31 Jul 2020 03:38:58 +0100 Matthew Wilcox wrote: > On Fri, Jul 31, 2020 at 10:39:39AM +0800, qiang.zhang@windriver.com wrote: > > The pool is being destroyed, all page which in the pool, > > should be free. if some page is still be use by somebody, > > we should not just output error logs, also should also add > > a warning message. > > There's already a warning message. What value does this actually have? Presumably so we get a backtrace in order to identify the errant caller. I added a bit to the changelog: : The pool is being destroyed so all pages which are in the pool should be : free. If some page is still in use by somebody, we should not just output : error logs, also should also add a WARN message so the stack backtrace may : be used to identify the caller.