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From: "Gaëtan Rivet" <gaetan.rivet@6wind.com>
To: Matan Azrad <matan@mellanox.com>
Cc: Thomas Monjalon <thomas@monjalon.net>,
	"dev@dpdk.org" <dev@dpdk.org>,
	"ferruh.yigit@intel.com" <ferruh.yigit@intel.com>
Subject: Re: [dpdk-dev] [PATCH v2] bus/vdev: fix scope of device list lock
Date: Tue, 22 May 2018 11:11:06 +0200	[thread overview]
Message-ID: <20180522091105.hmwnwkjejyu7f6vi@bidouze.vm.6wind.com> (raw)
In-Reply-To: <VI1PR0501MB26080120741BDB73593E6897D2950@VI1PR0501MB2608.eurprd05.prod.outlook.com>

On Mon, May 21, 2018 at 05:28:52PM +0000, Matan Azrad wrote:
> 
> 
> From: Thomas Monjalon
> > The lock vdev_device_list_lock was taken before calling "remove" function for
> > the device.
> > So it prevents to remove sub-devices (as in failsafe) inside its own "remove"
> > function, because of a deadlock.
> > 
> > The lock is now only protecting the device list inside the bus driver.
> > 
> > Fixes: 35f462839b69 ("bus/vdev: add lock on device list")
> > 
> > Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> Tested-by: Matan Azrad <matan@mellanox.com>

If these locks were necessary, they would be missing as well for
rte_devargs. Jianfeng inquired about it, I think it should be followed
upon.

Restricting the scope of the lock here could maybe re-introduce the bug
that motivated their introduction in the first place, as the
devargs_remove() is not in the critical section anymore.

However, this is an rte_devargs issue, not a vdev bus one, so
the fix makes sense and I'd like to have it ASAP for failsafe.
Without a vdev bus maintainer left:

Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>

-- 
Gaëtan Rivet
6WIND

  reply	other threads:[~2018-05-22  9:11 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-21 16:11 [dpdk-dev] [PATCH] bus/vdev: reduce " Thomas Monjalon
2018-05-21 16:45 ` [dpdk-dev] [PATCH v2] bus/vdev: fix " Thomas Monjalon
2018-05-21 17:28   ` Matan Azrad
2018-05-22  9:11     ` Gaëtan Rivet [this message]
2018-05-22  9:05 ` [dpdk-dev] [PATCH] bus/vdev: reduce " Burakov, Anatoly
2018-05-22  9:20   ` Thomas Monjalon
2018-05-22 11:37     ` [dpdk-dev] [PATCH v3] bus/vdev: replace device list lock by a recursive one Thomas Monjalon
2018-05-22 12:08       ` Matan Azrad
2018-05-22 13:34       ` Burakov, Anatoly
2018-05-22 14:38         ` Thomas Monjalon

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