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 DEB6AC64EC4 for ; Fri, 10 Mar 2023 15:24:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234236AbjCJPYE (ORCPT ); Fri, 10 Mar 2023 10:24:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48428 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234222AbjCJPXr (ORCPT ); Fri, 10 Mar 2023 10:23:47 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFE2F10C116 for ; Fri, 10 Mar 2023 07:13:41 -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 ams.source.kernel.org (Postfix) with ESMTPS id 16853B822F2 for ; Fri, 10 Mar 2023 15:12:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 810D3C433EF; Fri, 10 Mar 2023 15:12:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678461172; bh=MjHwDWz6yvoPlkxl5yRrWsG8ENeQff2EplY80xfHn2o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HUz70fk83Zq57ipJtdZpRSUeTMGwvRHf2uIvCfpoM4z1cj7asip79obj7Fs0hVDMp X2JjhdXamXv3u6AtjhL3t/QB8WYgJTEGFAKSGT8GLWWewFnLXNA92vxD1J5hPpXOO/ 1OQAIi4Vz9jJrtJTvquCYYmST7CZubR02DdSOgCg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Juergen Gross , Simon Horman , Dominique Martinet , Eric Van Hensbergen , Sasha Levin Subject: [PATCH 5.15 049/136] 9p/xen: fix connection sequence Date: Fri, 10 Mar 2023 14:42:51 +0100 Message-Id: <20230310133708.574662247@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133706.811226272@linuxfoundation.org> References: <20230310133706.811226272@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Juergen Gross [ Upstream commit c15fe55d14b3b4ded5af2a3260877460a6ffb8ad ] Today the connection sequence of the Xen 9pfs frontend doesn't match the documented sequence. It can work reliably only for a PV 9pfs device having been added at boot time already, as the frontend is not waiting for the backend to have set its state to "XenbusStateInitWait" before reading the backend properties from Xenstore. Fix that by following the documented sequence [1] (the documentation has a bug, so the reference is for the patch fixing that). [1]: https://lore.kernel.org/xen-devel/20230130090937.31623-1-jgross@suse.com/T/#u Link: https://lkml.kernel.org/r/20230130113036.7087-3-jgross@suse.com Fixes: 868eb122739a ("xen/9pfs: introduce Xen 9pfs transport driver") Signed-off-by: Juergen Gross Reviewed-by: Simon Horman Signed-off-by: Dominique Martinet Signed-off-by: Eric Van Hensbergen Signed-off-by: Sasha Levin --- net/9p/trans_xen.c | 38 +++++++++++++++++++++++--------------- 1 file changed, 23 insertions(+), 15 deletions(-) diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c index afa29f2a16050..9e4da8c1b907e 100644 --- a/net/9p/trans_xen.c +++ b/net/9p/trans_xen.c @@ -393,12 +393,11 @@ static int xen_9pfs_front_alloc_dataring(struct xenbus_device *dev, return ret; } -static int xen_9pfs_front_probe(struct xenbus_device *dev, - const struct xenbus_device_id *id) +static int xen_9pfs_front_init(struct xenbus_device *dev) { int ret, i; struct xenbus_transaction xbt; - struct xen_9pfs_front_priv *priv = NULL; + struct xen_9pfs_front_priv *priv = dev_get_drvdata(&dev->dev); char *versions, *v; unsigned int max_rings, max_ring_order, len = 0; @@ -426,11 +425,6 @@ static int xen_9pfs_front_probe(struct xenbus_device *dev, if (p9_xen_trans.maxsize > XEN_FLEX_RING_SIZE(max_ring_order)) p9_xen_trans.maxsize = XEN_FLEX_RING_SIZE(max_ring_order) / 2; - priv = kzalloc(sizeof(*priv), GFP_KERNEL); - if (!priv) - return -ENOMEM; - - priv->dev = dev; priv->num_rings = XEN_9PFS_NUM_RINGS; priv->rings = kcalloc(priv->num_rings, sizeof(*priv->rings), GFP_KERNEL); @@ -489,23 +483,35 @@ static int xen_9pfs_front_probe(struct xenbus_device *dev, goto error; } - write_lock(&xen_9pfs_lock); - list_add_tail(&priv->list, &xen_9pfs_devs); - write_unlock(&xen_9pfs_lock); - dev_set_drvdata(&dev->dev, priv); - xenbus_switch_state(dev, XenbusStateInitialised); - return 0; error_xenbus: xenbus_transaction_end(xbt, 1); xenbus_dev_fatal(dev, ret, "writing xenstore"); error: - dev_set_drvdata(&dev->dev, NULL); xen_9pfs_front_free(priv); return ret; } +static int xen_9pfs_front_probe(struct xenbus_device *dev, + const struct xenbus_device_id *id) +{ + struct xen_9pfs_front_priv *priv = NULL; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + dev_set_drvdata(&dev->dev, priv); + + write_lock(&xen_9pfs_lock); + list_add_tail(&priv->list, &xen_9pfs_devs); + write_unlock(&xen_9pfs_lock); + + return 0; +} + static int xen_9pfs_front_resume(struct xenbus_device *dev) { dev_warn(&dev->dev, "suspend/resume unsupported\n"); @@ -524,6 +530,8 @@ static void xen_9pfs_front_changed(struct xenbus_device *dev, break; case XenbusStateInitWait: + if (!xen_9pfs_front_init(dev)) + xenbus_switch_state(dev, XenbusStateInitialised); break; case XenbusStateConnected: -- 2.39.2