From patchwork Tue Dec 7 14:57:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antoine Tenart X-Patchwork-Id: 12662017 X-Patchwork-Delegate: kuba@kernel.org 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 EF167C433EF for ; Tue, 7 Dec 2021 14:57:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238315AbhLGPBI (ORCPT ); Tue, 7 Dec 2021 10:01:08 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:55604 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238310AbhLGPBI (ORCPT ); Tue, 7 Dec 2021 10:01:08 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1AC43B817EE for ; Tue, 7 Dec 2021 14:57:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 290ABC341C1; Tue, 7 Dec 2021 14:57:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638889055; bh=16Flt33efDjvoT5248LZ4hJJ36k614a6c89HvrrFups=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VSWNIVXMn/pdqpVa7T+X4rpnBVBYCkVy3lxoMRIonn2YhN5l/kxD0+HzJFhYMz+xA 6CBKpBFK4/PVuZVzChHWm/weMOg7waTO1V+sgwaTSU+zOcKLp3fHZ8WY58867MyTBD PUHc/E/az7IK2alIbRqn3XkM7QQwfV5MBBC9bxIm9npMZszYoJVh+XbFm8kUWwZuF+ nnaaVY7OiklBVfzXNE6/G4xiYmnVY76BmBxjYC543ibe60JY5btI7/l4TRdKp4qrFU RP642BifSUzy5zf4LjQ9E19uY2Y0F2Y/XjdOB1z/TX3R3FZBPGFy69YdfV6hw0nTyY oTSryttsaWA6g== From: Antoine Tenart To: davem@davemloft.net, kuba@kernel.org Cc: Antoine Tenart , alexander.duyck@gmail.com, netdev@vger.kernel.org Subject: [PATCH net-next 2/2] net-sysfs: warn if new queue objects are being created during device unregistration Date: Tue, 7 Dec 2021 15:57:25 +0100 Message-Id: <20211207145725.352657-3-atenart@kernel.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211207145725.352657-1-atenart@kernel.org> References: <20211207145725.352657-1-atenart@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Calling netdev_queue_update_kobjects is allowed during device unregistration since commit 5c56580b74e5 ("net: Adjust TX queue kobjects if number of queues changes during unregister"). But this is solely to allow queue unregistrations. Any path attempting to add new queues after a device started its unregistration should be fixed. This patch adds a warning to detect such illegal use. Signed-off-by: Antoine Tenart --- net/core/net-sysfs.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 33f408c24205..53ea262ecafd 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1694,6 +1694,13 @@ netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num) int i; int error = 0; + /* Tx queue kobjects are allowed to be updated when a device is being + * unregistered, but solely to remove queues from qdiscs. Any path + * adding queues should be fixed. + */ + WARN(dev->reg_state == NETREG_UNREGISTERING && new_num > old_num, + "New queues can't be registered after device unregistration."); + for (i = old_num; i < new_num; i++) { error = netdev_queue_add_kobject(dev, i); if (error) {