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 CA7F1C43219 for ; Tue, 1 Mar 2022 20:27:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238616AbiCAU2T (ORCPT ); Tue, 1 Mar 2022 15:28:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239251AbiCAUYh (ORCPT ); Tue, 1 Mar 2022 15:24:37 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27765B02; Tue, 1 Mar 2022 12:22:37 -0800 (PST) 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 dfw.source.kernel.org (Postfix) with ESMTPS id B593A60B5B; Tue, 1 Mar 2022 20:22:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2111DC340EF; Tue, 1 Mar 2022 20:22:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646166156; bh=aPLnTDcN5Cogu7sSosopTtKGWxetddHlbwS/+ePDwqU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h+UeU/zpRmHfhaCMfuhxF+u1Vz65yCguVXd6YqWMqQ9EwnBIAdimJOSMbh1mAA2Ms 84ZxX16WllwqYrGoHC6mgt0OLiTn4sqHEj8N0+1nlzOhG/c3wqsRz1iZN43zEJNX6C fOf4Cb2jJVVdUET9zwIB+H3zmJA7Caz4tE2pUgkXtzGXRkSGea/bqMf+C+8c3pO6ic URTUFe4V1gScGuoQ3D0Ekcj6AqUmhMRCtUvNeQ2y1vxYvRG7Kh5ET4Xm1PesL/gEUo 3Q0KWJJ2kRi0inmOpZ6BpBCsXbyHVleS9ScuehEAQi26couDLVPeTg2unOF1F5DL2M wOb7icT5FLxrA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?= , Paul Durrant , Michael Brown , Jakub Kicinski , Sasha Levin , wei.liu@kernel.org, davem@davemloft.net, xen-devel@lists.xenproject.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 4/6] Revert "xen-netback: Check for hotplug-status existence before watching" Date: Tue, 1 Mar 2022 15:22:08 -0500 Message-Id: <20220301202212.19419-4-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220301202212.19419-1-sashal@kernel.org> References: <20220301202212.19419-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 e6646c8a7bdbb..78788402edd8b 100644 --- a/drivers/net/xen-netback/xenbus.c +++ b/drivers/net/xen-netback/xenbus.c @@ -1040,15 +1040,11 @@ 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); -- 2.34.1