From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 15681A0542; Thu, 13 Feb 2020 13:37:10 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 06CEE1BFB4; Thu, 13 Feb 2020 13:37:09 +0100 (CET) Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) by dpdk.org (Postfix) with ESMTP id 5FB891BFA5 for ; Thu, 13 Feb 2020 13:37:07 +0100 (CET) Received: from compute1.internal (compute1.nyi.internal [10.202.2.41]) by mailout.nyi.internal (Postfix) with ESMTP id B777421D46; Thu, 13 Feb 2020 07:37:06 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute1.internal (MEProxy); Thu, 13 Feb 2020 07:37:06 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s=mesmtp; bh=IJ0a1k6brx21BxZKHv+KBnBxXJIIIPUywyuuAxKdTog=; b=PJQWvj9Vemgk IDTujY1ZIAwBYE7jTZiDBFSPd2+BD0acG1Dr3x5qYqFUk/8oqspteUNsh3+/VoSO AnYfhmv8dHZH0tuUYIZjttWiUFspsrHtTH5C6uio+iSmmP2nOkLP7zarETBbx63j 15tvHPWW/U7KbVdWyeo1J/YCejSXQQo= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm2; bh=IJ0a1k6brx21BxZKHv+KBnBxXJIIIPUywyuuAxKdT og=; b=3yWmkPrwSrwDlgexEJR2HudYV9z2FkcwKvDQ5+fV1uDboL9abGybxo0Zo XlTnCmXnFNq6EqqfpZk5q8XoixltrortYxt1kO3lNMLCbTgjuedUEYwzuqWhVxxN wq7FNb5MFX0s0luOqDUy5EjVmSlx5KpB9VyloeAuB6lQeYjkizKmqMF0+nnG+LcE zJ0u2zdrCafKL2xEM9lDqKTRThETfL54SW16ntRIHktDpOotT/YfCDQ9yH/F6i3R gedO9f0awMHgVcVVEq5oTYwvDxUlvdneucQjmzI2852x0cA17Oy+SNtLMH1OI/9n K7ugnCt1I6yQUH2Zj368YpX9bHuLg== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedugedrieekgdegudcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkjghfggfgtgesthfuredttddtvdenucfhrhhomhepvfhhohhmrghs ucfoohhnjhgrlhhonhcuoehthhhomhgrshesmhhonhhjrghlohhnrdhnvghtqeenucfkph epjeejrddufeegrddvtdefrddukeegnecuvehluhhsthgvrhfuihiivgeptdenucfrrghr rghmpehmrghilhhfrhhomhepthhhohhmrghssehmohhnjhgrlhhonhdrnhgvth X-ME-Proxy: Received: from xps.localnet (184.203.134.77.rev.sfr.net [77.134.203.184]) by mail.messagingengine.com (Postfix) with ESMTPA id 62ED13060B21; Thu, 13 Feb 2020 07:37:05 -0500 (EST) From: Thomas Monjalon To: Matan Azrad , Bernard Iremonger , Ferruh Yigit Cc: "dev@dpdk.org" , Gaetan Rivet , David Marchand , Jeff Guo , Qi Zhang Date: Thu, 13 Feb 2020 13:37:03 +0100 Message-ID: <1645032.4herOUoSWf@xps> In-Reply-To: <200f3f01-fedb-b795-a733-e135957e8e99@intel.com> References: <1573548459-6931-1-git-send-email-matan@mellanox.com> <200f3f01-fedb-b795-a733-e135957e8e99@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [dpdk-stable] [PATCH 2/2] app/testpmd: fix invalid port detaching X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Hi, This discussion becomes confusing so I do a summary below. I think we can do several fixes in 20.02. 12/02/2020 14:49, Ferruh Yigit: > On 2/3/2020 5:10 PM, Matan Azrad wrote: [stripping long discussion in favor of a summary below] > > Even if the PMD clear the device pointer, the testpmd still may release wrong rte_device. > > Yes it may, although that is less likely to occur, it requires a new device hot > added between close() and detach of the other device. > > Would you be agree to say there are two problems: > > 1) When testpmd close a port, a new attached port can re-use it over writing > some fields, relying the data structures of the closed port is not safe. > > 2) PMD not cleaning ethdev->device pointer in the .remove() may cause issues in > double detach of a port. > > > For (1) I suggest fixing it in the attach path, don't re-use an eth_dev port id > unless it is completely freed, may need to add new state for it. Does it make sense? Yes we could add a CLOSED state which is set on ethdev close. When the rte_device is freed, the PMD could set attached ports as UNUSED. But given some ethdev ports can be open and closed dynamically, I am not sure it is a good solution to keep them in CLOSED state and ask PMD to remember them. An alternative workaround could be to allocate port_id by incrementing a saved biggest id. So the race condition would be very unlikely. The drawbacks are having big port_id numbers and changing the id allocation algorithm (which is not documented anyway). The proposals above for port_id allocation or states rework cannot be done in 20.02. Let's discuss and work on it in a separated thread. > For (2) PMDs want to get hotplug support needs to fix it. Yes PMDs should clear rte_eth_devices[port_id].device in .remove(). We must also protect from user calling detach on a closed port by adding a check in cmd_operate_detach_port_parsed(), before calling detach_port_device(). The hotplug rmv_port_callback() must be able to call detach after close. There are three possible fixes: - revert the port_id_is_invalid() check in detach_port_device() - call rte_dev_remove(rte_device) directly - call a new function with rte_device (detach_port_device() can use it) About the function detach_port_device() itself, yes this function is strange to say the least. It was a convenience for detaching a rte_device from a port_id. The cleanup of siblings with RTE_ETH_FOREACH_DEV_OF(sibling, dev), should probably be removed. I've added it as a temporary solution before all PMDs are properly fixed: rte_eth_devices[sibling].device = NULL; For info, there is a function detach_device() used by the command "device detach "