From: Stephen Hemminger <stephen@networkplumber.org>
To: Ruifeng Wang <Ruifeng.Wang@arm.com>
Cc: fengchengwen <fengchengwen@huawei.com>,
Ashok Kaladi <ashok.k.kaladi@intel.com>,
"jerinj@marvell.com" <jerinj@marvell.com>,
"thomas@monjalon.net" <thomas@monjalon.net>,
Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>,
"dev@dpdk.org" <dev@dpdk.org>,
"s.v.naga.harish.k@intel.com" <s.v.naga.harish.k@intel.com>,
"erik.g.carrillo@intel.com" <erik.g.carrillo@intel.com>,
"abhinandan.gujjar@intel.com" <abhinandan.gujjar@intel.com>,
"stable@dpdk.org" <stable@dpdk.org>, nd <nd@arm.com>
Subject: Re: [PATCH 2/2] ethdev: fix race condition in fast-path ops setup
Date: Tue, 21 Feb 2023 09:00:53 -0800 [thread overview]
Message-ID: <20230221090053.14d653bf@hermes.local> (raw)
In-Reply-To: <AS8PR08MB70807961C29F10CE435DE4B89EA59@AS8PR08MB7080.eurprd08.prod.outlook.com>
On Tue, 21 Feb 2023 07:24:19 +0000
Ruifeng Wang <Ruifeng.Wang@arm.com> wrote:
> > -----Original Message-----
> > From: fengchengwen <fengchengwen@huawei.com>
> > Sent: Monday, February 20, 2023 2:58 PM
> > To: Ashok Kaladi <ashok.k.kaladi@intel.com>; jerinj@marvell.com; thomas@monjalon.net
> > Cc: dev@dpdk.org; s.v.naga.harish.k@intel.com; erik.g.carrillo@intel.com;
> > abhinandan.gujjar@intel.com; stable@dpdk.org; Ruifeng Wang <Ruifeng.Wang@arm.com>
> > Subject: Re: [PATCH 2/2] ethdev: fix race condition in fast-path ops setup
> >
> > On 2023/2/20 14:08, Ashok Kaladi wrote:
> > > If ethdev enqueue or dequeue function is called during
> > > eth_dev_fp_ops_setup(), it may get pre-empted after setting the
> > > function pointers, but before setting the pointer to port data.
> > > In this case the newly registered enqueue/dequeue function will use
> > > dummy port data and end up in seg fault.
> > >
> > > This patch moves the updation of each data pointers before updating
> > > corresponding function pointers.
> > >
> > > Fixes: c87d435a4d79 ("ethdev: copy fast-path API into separate
> > > structure")
> > > Cc: stable@dpdk.org
Why is something calling enqueue/dequeue when device is not fully started.
A correctly written application would not call rx/tx burst until after
ethdev start had finished.
Would something like this work better?
Note: there is another bug in current code. The check for link state interrupt
and link_ops could return -ENOTSUP and leave device in indeterminate state.
The check should be done before calling PMD.
diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 0266cc82acb6..d6c163ed85e7 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -1582,6 +1582,14 @@ rte_eth_dev_start(uint16_t port_id)
return 0;
}
+ if (dev->data->dev_conf.intr_conf.lsc == 0 &&
+ dev->dev_ops->link_update == NULL) {
+ RTE_ETHDEV_LOG(INFO,
+ "Device with port_id=%"PRIu16" link update not supported\n",
+ port_id);
+ return -ENOTSUP;
+ }
+
ret = rte_eth_dev_info_get(port_id, &dev_info);
if (ret != 0)
return ret;
@@ -1591,9 +1599,7 @@ rte_eth_dev_start(uint16_t port_id)
eth_dev_mac_restore(dev, &dev_info);
diag = (*dev->dev_ops->dev_start)(dev);
- if (diag == 0)
- dev->data->dev_started = 1;
- else
+ if (diag != 0)
return eth_err(port_id, diag);
ret = eth_dev_config_restore(dev, &dev_info, port_id);
@@ -1611,16 +1617,18 @@ rte_eth_dev_start(uint16_t port_id)
return ret;
}
- if (dev->data->dev_conf.intr_conf.lsc == 0) {
- if (*dev->dev_ops->link_update == NULL)
- return -ENOTSUP;
- (*dev->dev_ops->link_update)(dev, 0);
- }
-
/* expose selection of PMD fast-path functions */
eth_dev_fp_ops_setup(rte_eth_fp_ops + port_id, dev);
+ /* ensure state is set before marking device ready */
+ rte_smp_wmb();
+
rte_ethdev_trace_start(port_id);
+
+ /* Update current link state */
+ if (dev->data->dev_conf.intr_conf.lsc == 0)
+ (*dev->dev_ops->link_update)(dev, 0);
+
return 0;
}
next prev parent reply other threads:[~2023-02-21 17:00 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-20 6:08 [PATCH 1/2] eventdev: fix race condition in fast-path set function Ashok Kaladi
2023-02-20 6:08 ` [PATCH 2/2] ethdev: fix race condition in fast-path ops setup Ashok Kaladi
2023-02-20 6:57 ` fengchengwen
2023-02-21 7:24 ` Ruifeng Wang
2023-02-21 17:00 ` Stephen Hemminger [this message]
2023-02-22 1:07 ` fengchengwen
2023-02-22 9:41 ` Ruifeng Wang
2023-02-22 10:41 ` Konstantin Ananyev
2023-02-22 22:48 ` Honnappa Nagarahalli
2023-02-23 1:15 ` Stephen Hemminger
2023-02-23 4:47 ` Honnappa Nagarahalli
2023-02-23 4:40 ` Honnappa Nagarahalli
2023-02-23 8:23 ` fengchengwen
2023-02-23 13:31 ` Konstantin Ananyev
2023-02-25 1:32 ` fengchengwen
2023-02-28 23:57 ` Honnappa Nagarahalli
2023-02-20 7:01 ` fengchengwen
2023-02-20 9:44 ` Konstantin Ananyev
2023-03-03 16:49 ` Ferruh Yigit
-- strict thread matches above, loose matches on Subject: below --
2023-02-20 6:06 [PATCH 1/2] eventdev: fix race condition in fast-path set function Ashok Kaladi
2023-02-20 6:06 ` [PATCH 2/2] ethdev: fix race condition in fast-path ops setup Ashok Kaladi
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