From patchwork Mon Mar 14 11:53:37 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 551703 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 D3C95C43217 for ; Mon, 14 Mar 2022 12:11:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240810AbiCNMMU (ORCPT ); Mon, 14 Mar 2022 08:12:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59498 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240737AbiCNMHn (ORCPT ); Mon, 14 Mar 2022 08:07:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D51125C41; Mon, 14 Mar 2022 05:03:47 -0700 (PDT) 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 AF26AB80DEC; Mon, 14 Mar 2022 12:03:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0483C340E9; Mon, 14 Mar 2022 12:03:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1647259424; bh=uOsQL9HfOvgoX8ZoU4HLVyKTxiRuAnywjsKCJfwE/AI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Pr0iFM6LXzi/3nre3H1xq9JxVoga3YK5XQAXMGQgQti7jKygouSUXrUyyVKlSz1mn gKYewOBz2n+qh3BjysF5lDBs5FdTXpYdRhw3FQXCfKrUWO6ZXvbzcQJNGh89o4kkIS musP+ec+0DNAALRS+pW+y+1FbQsAbwt5OSHiSzjs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?utf-8?q?Marek_Marczykowski-G=C3=B3recki?= , Paul Durrant , Michael Brown , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.10 44/71] Revert "xen-netback: Check for hotplug-status existence before watching" Date: Mon, 14 Mar 2022 12:53:37 +0100 Message-Id: <20220314112739.164179884@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220314112737.929694832@linuxfoundation.org> References: <20220314112737.929694832@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Marek Marczykowski-Górecki [ Upstream commit e8240addd0a3919e0fd7436416afe9aa6429c484 ] This reverts commit 2afeec08ab5c86ae21952151f726bfe184f6b23d. The reasoning in the commit was wrong - the code expected to setup the watch even if 'hotplug-status' didn't exist. In fact, it relied on the watch being fired the first time - to check if maybe 'hotplug-status' is already set to 'connected'. Not registering a watch for non-existing path (which is the case if hotplug script hasn't been executed yet), made the backend not waiting for the hotplug script to execute. This in turns, made the netfront think the interface is fully operational, while in fact it was not (the vif interface on xen-netback side might not be configured yet). This was a workaround for 'hotplug-status' erroneously being removed. But since that is reverted now, the workaround is not necessary either. More discussion at https://lore.kernel.org/xen-devel/afedd7cb-a291-e773-8b0d-4db9b291fa98@ipxe.org/T/#u Signed-off-by: Marek Marczykowski-Górecki Reviewed-by: Paul Durrant Reviewed-by: Michael Brown Link: https://lore.kernel.org/r/20220222001817.2264967-2-marmarek@invisiblethingslab.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/xen-netback/xenbus.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c index 7acf3940dc1f..ca261e0fc9c9 100644 --- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c @@ -824,15 +824,11 @@ static void connect(struct backend_info *be) xenvif_carrier_on(be->vif); unregister_hotplug_status_watch(be); - if (xenbus_exists(XBT_NIL, dev->nodename, "hotplug-status")) { - err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, - NULL, hotplug_status_changed, - "%s/%s", dev->nodename, - "hotplug-status"); - if (err) - goto err; + err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, NULL, + hotplug_status_changed, + "%s/%s", dev->nodename, "hotplug-status"); + if (!err) be->have_hotplug_status_watch = 1; - } netif_tx_wake_all_queues(be->vif->dev);