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 A7E34C3F2D4 for ; Wed, 6 Jul 2022 06:55:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229740AbiGFGzN (ORCPT ); Wed, 6 Jul 2022 02:55:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229477AbiGFGzM (ORCPT ); Wed, 6 Jul 2022 02:55:12 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E21F1B79C; Tue, 5 Jul 2022 23:55:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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; bh=ik/uJsE+zpdPuUdS11m0Q/X6NmB5A5tIeaLT1FExMqk=; b=HHs4PsCAW1BgdmGMF7lVwPZBlR WXelzySoHmOcfeyjYIDcxKxiSPrY3LgVkMWP06N+b1YMeIjqTQqibdKCLa3W3s6TISEEwPbYtz9hf BuIfwbhWwKLUHmKXNlqKTzZIYUbxhMSDKDYDdgAErXVCEYOpTmfAM4yMn9tEpniYFBvxBn76mxl2y bsyyRpfl1bgczxu9jW5/iSXW5sl1VvDaH7+wHUdC+IDz12TBfxUbxNt4TIWkoXcBraRCmAoI9xGPy vLhJBjwY9NsA2OjzsrT2pWrhwOn/GsnSIQUmBOpgVrLFDDuEAHUBsL2PiXUaquNnBt0KfA6OTgFvJ BQurlmbA==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1o8yvy-006rFh-Ez; Wed, 06 Jul 2022 06:54:50 +0000 Date: Tue, 5 Jul 2022 23:54:50 -0700 From: Christoph Hellwig To: Nicolin Chen Cc: kwankhede@nvidia.com, corbet@lwn.net, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, zhenyuw@linux.intel.com, zhi.a.wang@intel.com, jani.nikula@linux.intel.com, joonas.lahtinen@linux.intel.com, rodrigo.vivi@intel.com, tvrtko.ursulin@linux.intel.com, airlied@linux.ie, daniel@ffwll.ch, farman@linux.ibm.com, mjrosato@linux.ibm.com, pasic@linux.ibm.com, vneethv@linux.ibm.com, oberpar@linux.ibm.com, freude@linux.ibm.com, akrowiak@linux.ibm.com, jjherne@linux.ibm.com, alex.williamson@redhat.com, cohuck@redhat.com, jgg@nvidia.com, kevin.tian@intel.com, hch@infradead.org, jchrist@linux.ibm.com, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, intel-gvt-dev@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Subject: Re: [RFT][PATCH v2 1/9] vfio: Make vfio_unpin_pages() return void Message-ID: References: <20220706062759.24946-1-nicolinc@nvidia.com> <20220706062759.24946-2-nicolinc@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220706062759.24946-2-nicolinc@nvidia.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org > +void vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, > + int npage) > { > struct vfio_container *container; > struct vfio_iommu_driver *driver; > - int ret; > > - if (!user_pfn || !npage || !vfio_assert_device_open(device)) > - return -EINVAL; > + if (WARN_ON_ONCE(!user_pfn || !npage || !vfio_assert_device_open(device))) This adds an overly long line. Note that I think in general it is better to have an individual WARN_ON per condition anyway, as that allows to directly pinpoint what went wrong when it triggers. > + if (WARN_ON_ONCE(unlikely(!driver || !driver->ops->unpin_pages))) > + return; I'd just skip this check an let it crash. If someone calls unpin on something totally random that wasn't even pinned we don't need to handle that gracefully. Otherwise looks good: Reviewed-by: Christoph Hellwig