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=-6.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 80F87C3A5A1 for ; Wed, 28 Aug 2019 21:37:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 53B2122DA7 for ; Wed, 28 Aug 2019 21:37:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726907AbfH1Vg7 (ORCPT ); Wed, 28 Aug 2019 17:36:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58562 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726828AbfH1Vg6 (ORCPT ); Wed, 28 Aug 2019 17:36:58 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 819EC75752; Wed, 28 Aug 2019 21:36:58 +0000 (UTC) Received: from x1.home (ovpn-116-131.phx2.redhat.com [10.3.116.131]) by smtp.corp.redhat.com (Postfix) with ESMTP id DDAA6600CD; Wed, 28 Aug 2019 21:36:57 +0000 (UTC) Date: Wed, 28 Aug 2019 15:36:52 -0600 From: Alex Williamson To: Parav Pandit Cc: jiri@mellanox.com, kwankhede@nvidia.com, cohuck@redhat.com, davem@davemloft.net, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH v1 2/5] mdev: Make mdev alias unique among all mdevs Message-ID: <20190828153652.7eb6d6d6@x1.home> In-Reply-To: <20190827191654.41161-3-parav@mellanox.com> References: <20190826204119.54386-1-parav@mellanox.com> <20190827191654.41161-1-parav@mellanox.com> <20190827191654.41161-3-parav@mellanox.com> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Wed, 28 Aug 2019 21:36:58 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, 27 Aug 2019 14:16:51 -0500 Parav Pandit wrote: > Mdev alias should be unique among all the mdevs, so that when such alias > is used by the mdev users to derive other objects, there is no > collision in a given system. > > Signed-off-by: Parav Pandit > > --- > Changelog: > v0->v1: > - Fixed inclusiong of alias for NULL check > - Added ratelimited debug print for sha1 hash collision error > --- > drivers/vfio/mdev/mdev_core.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c > index 62d29f57fe0c..4b9899e40665 100644 > --- a/drivers/vfio/mdev/mdev_core.c > +++ b/drivers/vfio/mdev/mdev_core.c > @@ -375,6 +375,13 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, > ret = -EEXIST; > goto mdev_fail; > } > + if (tmp->alias && alias && strcmp(tmp->alias, alias) == 0) { Nit, test if the device we adding has an alias before the device we're testing against. The compiler can better optimize keeping alias hot. Thanks, Alex > + mutex_unlock(&mdev_list_lock); > + ret = -EEXIST; > + dev_dbg_ratelimited(dev, "Hash collision in alias creation for UUID %pUl\n", > + uuid); > + goto mdev_fail; > + } > } > > mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);