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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10D8CC46467 for ; Wed, 4 Jan 2023 20:00:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235234AbjADUAM (ORCPT ); Wed, 4 Jan 2023 15:00:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235399AbjADUAI (ORCPT ); Wed, 4 Jan 2023 15:00:08 -0500 Received: from mail-wm1-x32a.google.com (mail-wm1-x32a.google.com [IPv6:2a00:1450:4864:20::32a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4BD133FA14 for ; Wed, 4 Jan 2023 12:00:05 -0800 (PST) Received: by mail-wm1-x32a.google.com with SMTP id m26-20020a05600c3b1a00b003d9811fcaafso20897990wms.5 for ; Wed, 04 Jan 2023 12:00:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=OG/y7xAe7GoU0v2u69k5lX/4KZLOEKX6GSOlMx3yuAQ=; b=jYTbS3tWP5PjKTYguj167jAFjYT2aPGkce/WrztXbN63Z0CVQr8Ld4Ac8efgxoL6DU ik3X9qtPNJEwy3wyFX1Ukf/DSERctCvNrNYUhM8W7RM9rm/3AQnMaGRJd4ID1dF4z3es dt0JeIWznmQgBiEyCqeYHezX8Vlzv9AtyGx9j9mm/qpDi8xZO5LkI78dyqrdoDDVQOaF nhUydsFwnoSvW3z8OOHlFeG7mk0+FJHB5RMEpQr7jTewbhwVtcYJisIUoI/YreJuAYtf 87yGTnNs/lEO7qGx/rTR4yQJdWwAs/wXt+LpBqlvRNAzxAfcW6vWXEIz2mhZ25aq0t1R kmwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=OG/y7xAe7GoU0v2u69k5lX/4KZLOEKX6GSOlMx3yuAQ=; b=Wn/WRPFJ8NUYtWOhHK+pykuprnhNoBPaDmTTzTtDC3QmuD4tbJWtW3BuJQwCBZi/hm 2faDaXRVgjx0E+30E1FeXZMHeoCo8X72c0qoPvhUxCbfewvaYJuzWmqgFPpCEZcTY3D9 vRyh9JMMZy7vzgtNUJFd86IrK7Aj/HkU4rfjB7Voae93v9YTtEL3Ww/H//i5+qRS8BRN DK5tTxvpYMIPpX6VxC0IjpAa2WamrVzEBInYeNwttZ/5q/Qs5CC4PBAdlOpocinOmS69 mb9a/O5inr4bRSXTpuJl4aWqesC0yoa7iWzpH6t/49wSujoeZi+ftiMQtSYOkSBv0KBR IKKw== X-Gm-Message-State: AFqh2kpK/FY3d5912nhdOjW67FBmGGcL9+qOxVQFy/osNpuyiXOHHX8D k8DYthRGJSRzvEP0wUm12shGQyN+jpI= X-Google-Smtp-Source: AMrXdXvfqTH0p/eJd0SwsLoZc2HcLfB3obqg0ghT/R+iy//w4COBtg/aXwEj7yayc8kTGnyia5x5pg== X-Received: by 2002:a05:600c:54c2:b0:3d3:3c74:dbd0 with SMTP id iw2-20020a05600c54c200b003d33c74dbd0mr34390181wmb.13.1672862403849; Wed, 04 Jan 2023 12:00:03 -0800 (PST) Received: from localhost (host81-157-153-247.range81-157.btcentralplus.com. [81.157.153.247]) by smtp.gmail.com with ESMTPSA id j20-20020a05600c191400b003b4fe03c881sm59068351wmq.48.2023.01.04.12.00.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 Jan 2023 12:00:03 -0800 (PST) Date: Wed, 4 Jan 2023 20:00:02 +0000 From: Lorenzo Stoakes To: "Yu, Fenghua" Cc: Alistair Popple , Vinod Koul , "Jiang, Dave" , "dmaengine@vger.kernel.org" , "Zhu, Tony" , Andrew Morton , "linux-mm@kvack.org" , Christoph Hellwig , "Shankar, Ravi V" Subject: Re: [PATCH 09/17] mm: export access_remote_vm() symbol Message-ID: References: <20230103163505.1569356-1-fenghua.yu@intel.com> <20230103163505.1569356-10-fenghua.yu@intel.com> <87tu16rdea.fsf@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On Wed, Jan 04, 2023 at 07:00:55PM +0000, Yu, Fenghua wrote: > So the current patch is good without any change, right? No, you'd definitely need mmget_not_zero() (and a grab in advance of this, though from the sounds of it you may already have it), I definitely don't think the patch as-is works, see my reply to Alistair.