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 58C78C433EF for ; Tue, 22 Feb 2022 10:55:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231557AbiBVK4Q (ORCPT ); Tue, 22 Feb 2022 05:56:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231499AbiBVK4P (ORCPT ); Tue, 22 Feb 2022 05:56:15 -0500 X-Greylist: delayed 427 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 22 Feb 2022 02:55:50 PST Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B5D3C15DB1E; Tue, 22 Feb 2022 02:55:50 -0800 (PST) Received: from compute2.internal (compute2.nyi.internal [10.202.2.46]) by mailout.nyi.internal (Postfix) with ESMTP id 097C65C0194; Tue, 22 Feb 2022 05:48:43 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Tue, 22 Feb 2022 05:48:43 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=DTcsRQMhHEsT227VK XKHQyOwB4dIKR9vzR6umqoiTuA=; b=K8S59BhMrGaVw44sfUv7enmQYQ1OVuGmQ lpQdCdIjz71gjc8sElBsakHzdjkF/fWn3d2LPUPcfAoivcwe+LV83yvizXy8vaL1 XfMNOT3uVokxiK0Dva1CKvI7FSrewINC6IUECvQlEIoHu9w78/f2s1fKyDF0INbC HsSLcrmRrIJT5/+vRozrUSm9SO5w8lMCyFGd2ChhAXZh3hkFf0pXORVGYOZr7yVd GeRS8M7Rk4riPYq9RsXhn/5WS8f2iwWDDgYwCpcC03bJO/hvHEar5Wn/qy+5Rshm Z+nH9mO4qHq+ZgELZ0kT+6wttK1YoXw3Oispb/yo3+GGM8PXWifbQ== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrkeekgddulecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujgesghdtreertddtjeenucfhrhhomhepofgrrhgvkhcu ofgrrhgtiiihkhhofihskhhiqdfikphrvggtkhhiuceomhgrrhhmrghrvghksehinhhvih hsihgslhgvthhhihhnghhslhgrsgdrtghomheqnecuggftrfgrthhtvghrnhepheevvdeu veehkeehhfevgffggfevudegteeugfeliedvhefgueeiuefgteetieffnecuffhomhgrih hnpehkvghrnhgvlhdrohhrghenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhep mhgrihhlfhhrohhmpehmrghrmhgrrhgvkhesihhnvhhishhisghlvghthhhinhhgshhlrg gsrdgtohhm X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Tue, 22 Feb 2022 05:48:41 -0500 (EST) Date: Tue, 22 Feb 2022 11:48:38 +0100 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Roger Pau =?utf-8?B?TW9ubsOp?= Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Michael Brown , Wei Liu , Paul Durrant , "David S. Miller" , Jakub Kicinski , "moderated list:XEN NETWORK BACKEND DRIVER" , "open list:XEN NETWORK BACKEND DRIVER" Subject: Re: [PATCH v2 2/2] Revert "xen-netback: Check for hotplug-status existence before watching" Message-ID: References: <20220222001817.2264967-1-marmarek@invisiblethingslab.com> <20220222001817.2264967-2-marmarek@invisiblethingslab.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="0J0yTdf+LQeqmBEg" Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --0J0yTdf+LQeqmBEg Content-Type: text/plain; protected-headers=v1; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Date: Tue, 22 Feb 2022 11:48:38 +0100 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Roger Pau =?utf-8?B?TW9ubsOp?= Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Michael Brown , Wei Liu , Paul Durrant , "David S. Miller" , Jakub Kicinski , "moderated list:XEN NETWORK BACKEND DRIVER" , "open list:XEN NETWORK BACKEND DRIVER" Subject: Re: [PATCH v2 2/2] Revert "xen-netback: Check for hotplug-status existence before watching" On Tue, Feb 22, 2022 at 09:31:31AM +0100, Roger Pau Monn=C3=A9 wrote: > On Tue, Feb 22, 2022 at 01:18:17AM +0100, Marek Marczykowski-G=C3=B3recki= wrote: > > This reverts commit 2afeec08ab5c86ae21952151f726bfe184f6b23d. > >=20 > > 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). > >=20 > > This was a workaround for 'hotplug-status' erroneously being removed. > > But since that is reverted now, the workaround is not necessary either. > >=20 > > More discussion at > > https://lore.kernel.org/xen-devel/afedd7cb-a291-e773-8b0d-4db9b291fa98@= ipxe.org/T/#u > >=20 > > Cc: stable@vger.kernel.org > > Signed-off-by: Marek Marczykowski-G=C3=B3recki > > --- > > I believe this is the same issue as discussed at > > https://lore.kernel.org/xen-devel/20220113111946.GA4133739@dingwall.me.= uk/ >=20 > Right - I believe we need to leave that workaround in place in libxl > in order to deal with bogus Linux netbacks? I'm afraid so, yes. --=20 Best Regards, Marek Marczykowski-G=C3=B3recki Invisible Things Lab --0J0yTdf+LQeqmBEg Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhrpukzGPukRmQqkK24/THMrX1ywFAmIUv4YACgkQ24/THMrX 1yyKoggAg6fLt83xdWaCGP1TaH51wysnBj1sxuSzFeh7BUVHdyWYYlfTAQ+Ytghr N4uCqUyXqTpheDM7BE/9pXSiuHH1WqmClAef7SF9MweHT0zvDkL0J7McMSqLBeG4 Qj67yHz4/C1yAhN3dAdP8933l4nmzvzOGNdG77D3P1IvU+41xtyoZPVfH5DDNscG yfYwoeI/oYRNtvd1H7+UD3ANkwEjnmFIVGRtFcb7G+NH+d9vGQFbODww95oCbWWA PfKL7gBFGNDuNnIABFCoI/RsF523zRSSeBesdAImUM+531IRapB9J9FYp4E6M3RA Bt5hPaIrX6OFgur2u9aShGvIdH+FYQ== =0A40 -----END PGP SIGNATURE----- --0J0yTdf+LQeqmBEg--