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=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 6CB2CC83000 for ; Tue, 28 Apr 2020 13:59:03 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 27424206D6 for ; Tue, 28 Apr 2020 13:59:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 27424206D6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 49BNY04HXCzDqTm for ; Tue, 28 Apr 2020 23:59:00 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 49BNQC2Vn3zDqMW for ; Tue, 28 Apr 2020 23:53:07 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) by bilbo.ozlabs.org (Postfix) with ESMTP id 49BNPz2x5Sz8t15 for ; Tue, 28 Apr 2020 23:52:55 +1000 (AEST) Received: by ozlabs.org (Postfix) id 49BNPw5RYWz9sSy; Tue, 28 Apr 2020 23:52:52 +1000 (AEST) Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 49BNPv5Cldz9sSX; Tue, 28 Apr 2020 23:52:50 +1000 (AEST) Received: by verein.lst.de (Postfix, from userid 2407) id 3C3B868CEC; Tue, 28 Apr 2020 15:52:46 +0200 (CEST) Date: Tue, 28 Apr 2020 15:52:45 +0200 From: Christoph Hellwig To: Michael Ellerman Subject: Re: [PATCH] powerpc/spufs: Add rcu_read_lock() around fcheck() Message-ID: <20200428135245.GA2827@lst.de> References: <20200428114811.68436-1-mpe@ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200428114811.68436-1-mpe@ellerman.id.au> User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, hch@lst.de, viro@zeniv.linux.org.uk, jk@ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Tue, Apr 28, 2020 at 09:48:11PM +1000, Michael Ellerman wrote: > > This comes from fcheck_files() via fcheck(). > > It's pretty clearly documented that fcheck() must be wrapped with > rcu_read_lock(), so fix it. But for this to actually be useful you'd need the rcu read lock until your are done with the file (or got a reference).