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From: Stephen Hemminger <stephen@networkplumber.org>
To: Thomas Monjalon <thomas@monjalon.net>
Cc: dev@dpdk.org, Matan Azrad <matan@mellanox.com>, stable@dpdk.org
Subject: Re: [dpdk-dev] [PATCH 07/11] ethdev: add lock to port allocation check
Date: Thu, 10 May 2018 13:33:56 -0700	[thread overview]
Message-ID: <20180510133356.0c4bacb0@xeon-e3> (raw)
In-Reply-To: <20180509094337.26112-8-thomas@monjalon.net>

On Wed,  9 May 2018 11:43:33 +0200
Thomas Monjalon <thomas@monjalon.net> wrote:

>  
> +struct rte_eth_dev *
> +rte_eth_dev_allocated(const char *name)
> +{
> +	struct rte_eth_dev *ethdev;
> +
> +	rte_eth_dev_shared_data_prepare();
> +
> +	rte_spinlock_lock(&rte_eth_dev_shared_data->ownership_lock);
> +
> +	ethdev = rte_eth_dev_allocated_lock_free(name);
> +
> +	rte_spinlock_unlock(&rte_eth_dev_shared_data->ownership_lock);
> +
> +	return ethdev;
> +}
> +

Not sure about this. The code it self is correct, but it creates
a racy semantic.

If caller doesn't already hold a lock then there is no guarantee that
the device returned won't be destroyed by some other thread or that
the name was just allocated by some other process.

  parent reply	other threads:[~2018-05-10 20:33 UTC|newest]

Thread overview: 89+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-09  9:43 [dpdk-dev] [PATCH 00/11] ethdev: fix race conditions in iterator and notifications Thomas Monjalon
2018-05-09  9:43 ` [dpdk-dev] [PATCH 01/11] ethdev: fix debug log of owner id Thomas Monjalon
2018-05-09 17:53   ` [dpdk-dev] [dpdk-stable] " Ferruh Yigit
2018-05-09  9:43 ` [dpdk-dev] [PATCH 02/11] net/failsafe: fix sub-device visibility Thomas Monjalon
2018-05-09 12:13   ` Gaëtan Rivet
2018-05-09 12:21     ` Thomas Monjalon
2018-05-09  9:43 ` [dpdk-dev] [PATCH 03/11] ethdev: add doxygen comments for each state Thomas Monjalon
2018-05-09 17:54   ` Ferruh Yigit
2018-05-09  9:43 ` [dpdk-dev] [PATCH 04/11] drivers/net: use higher level of probing helper for PCI Thomas Monjalon
2018-05-09 17:54   ` Ferruh Yigit
2018-05-09  9:43 ` [dpdk-dev] [PATCH 05/11] ethdev: add probing finish function Thomas Monjalon
2018-05-10 20:18   ` Stephen Hemminger
2018-05-10 21:49     ` Thomas Monjalon
2018-05-09  9:43 ` [dpdk-dev] [PATCH 06/11] ethdev: allow ownership operations on unused port Thomas Monjalon
2018-05-09 18:00   ` Ferruh Yigit
2018-05-09 19:05     ` Thomas Monjalon
2018-05-10 20:26   ` Stephen Hemminger
2018-05-10 21:53     ` Thomas Monjalon
2018-05-09  9:43 ` [dpdk-dev] [PATCH 07/11] ethdev: add lock to port allocation check Thomas Monjalon
2018-05-09 12:21   ` Gaëtan Rivet
2018-05-09 12:25     ` Thomas Monjalon
2018-05-10 20:35     ` Stephen Hemminger
2018-05-10 22:13       ` Thomas Monjalon
2018-05-10 23:47         ` Thomas Monjalon
2018-05-10 20:33   ` Stephen Hemminger [this message]
2018-05-10 22:10     ` Thomas Monjalon
2018-05-10 22:29       ` Stephen Hemminger
2018-05-09  9:43 ` [dpdk-dev] [PATCH 08/11] ethdev: fix port visibility before initialization Thomas Monjalon
2018-05-09 18:03   ` [dpdk-dev] [dpdk-stable] " Ferruh Yigit
2018-05-09 19:08     ` Thomas Monjalon
2018-05-10 20:40   ` [dpdk-dev] " Stephen Hemminger
2018-05-10 22:18     ` Thomas Monjalon
2018-05-09  9:43 ` [dpdk-dev] [PATCH 09/11] ethdev: fix port probing notification Thomas Monjalon
2018-05-09 18:07   ` [dpdk-dev] [dpdk-stable] " Ferruh Yigit
2018-05-09 19:13     ` Thomas Monjalon
2018-05-09  9:43 ` [dpdk-dev] [PATCH 10/11] net/failsafe: fix sub-device ownership race Thomas Monjalon
2018-05-09 12:41   ` Gaëtan Rivet
2018-05-09 13:01     ` Matan Azrad
2018-05-09 13:30       ` Gaëtan Rivet
2018-05-09 13:43         ` Thomas Monjalon
2018-05-09 14:03           ` Gaëtan Rivet
2018-05-09 21:59             ` [dpdk-dev] [dpdk-stable] " Thomas Monjalon
2018-05-09 13:26     ` [dpdk-dev] " Thomas Monjalon
2018-05-09  9:43 ` [dpdk-dev] [PATCH 11/11] ethdev: fix port removal notification timing Thomas Monjalon
2018-05-09 18:07   ` [dpdk-dev] [dpdk-stable] " Ferruh Yigit
2018-05-09 22:43 ` [dpdk-dev] [PATCH v2 00/11] ethdev: fix race conditions in iterator and notifications Thomas Monjalon
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 01/11] ethdev: fix debug log of owner id Thomas Monjalon
2018-05-10  9:49     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 02/11] net/failsafe: fix sub-device visibility Thomas Monjalon
2018-05-10  9:55     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 03/11] ethdev: add doxygen comments for each state Thomas Monjalon
2018-05-10  9:56     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 04/11] drivers/net: use higher level of probing helper for PCI Thomas Monjalon
2018-05-10 10:03     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 05/11] ethdev: add probing finish function Thomas Monjalon
2018-05-10 10:37     ` Andrew Rybchenko
2018-05-10 10:54       ` Thomas Monjalon
2018-05-10 11:24         ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 06/11] ethdev: allow ownership operations on unused port Thomas Monjalon
2018-05-10 10:41     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 07/11] ethdev: add lock to port allocation check Thomas Monjalon
2018-05-10 10:44     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 08/11] ethdev: fix port visibility before initialization Thomas Monjalon
2018-05-10 10:52     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 09/11] ethdev: fix port probing notification Thomas Monjalon
2018-05-10 10:53     ` Andrew Rybchenko
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 10/11] net/failsafe: fix sub-device ownership race Thomas Monjalon
2018-05-10 11:15     ` Andrew Rybchenko
2018-05-10 12:03       ` Matan Azrad
2018-05-09 22:43   ` [dpdk-dev] [PATCH v2 11/11] ethdev: fix port removal notification timing Thomas Monjalon
2018-05-10 11:17     ` Andrew Rybchenko
2018-05-10 11:19   ` [dpdk-dev] [PATCH v2 00/11] ethdev: fix race conditions in iterator and notifications Andrew Rybchenko
2018-05-10 16:23   ` Gaëtan Rivet
2018-05-10 22:27 ` [dpdk-dev] [PATCH " Stephen Hemminger
2018-05-10 23:58 ` [dpdk-dev] [PATCH v3 " Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 01/11] ethdev: fix debug log of owner id Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 02/11] net/failsafe: fix sub-device visibility Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 03/11] ethdev: add doxygen comments for each state Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 04/11] drivers/net: use higher level of probing helper for PCI Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 05/11] ethdev: add probing finish function Thomas Monjalon
2018-05-23 10:09     ` Ferruh Yigit
2018-05-23 10:14       ` Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 06/11] ethdev: allow ownership operations on unused port Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 07/11] ethdev: add lock to port allocation check Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 08/11] ethdev: fix port visibility before initialization Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 09/11] ethdev: fix port probing notification Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 10/11] net/failsafe: fix sub-device ownership race Thomas Monjalon
2018-05-10 23:58   ` [dpdk-dev] [PATCH v3 11/11] ethdev: fix port removal notification timing Thomas Monjalon
2018-05-11  1:14   ` [dpdk-dev] [PATCH v3 00/11] ethdev: fix race conditions in iterator and notifications Ferruh Yigit

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