On 3/10/2023 1:52 AM, Stephen Hemminger wrote:
On Thu, 9 Mar 2023 17:19:59 +0000
"Dumitrescu, Cristian" <cristian.dumitre...@intel.com> wrote:
-----Original Message-----
From: Stephen Hemminger <step...@networkplumber.org>
Sent: Thursday, March 9, 2023 4:31 PM
To: Jangra, Yogesh <yogesh.jan...@intel.com>
Cc: dev@dpdk.org; Dumitrescu, Cristian <cristian.dumitre...@intel.com>; R,
Kamalakannan <kamalakanna...@intel.com>; Suresh Narayane, Harshad
<harshad.suresh.naray...@intel.com>
Subject: Re: [PATCH] app/testpmd: fix closing softnic port before ethdev ports
On Thu, 9 Mar 2023 14:42:49 +0000
Yogesh Jangra <yogesh.jan...@intel.com> wrote:
+ /*
+ * SoftNIC runs on the sevice core, it uses the resources from
+ * the testpmd application. When we run quit command, the
testpmd
+ * application stops ethdev ports first, SoftNIC will try to
+ * access the port and sometimes that result in segmentation
+ * error. So first closing the SoftNIC port.
+ */
+ RTE_ETH_FOREACH_DEV(pt_id) {
+ if (!strcmp(ports[pt_id].dev_info.driver_name,
"net_softnic")) {
+ stop_port(pt_id);
+ close_port(pt_id);
+ }
+ }
+
NAK
No driver specific hacks please.
Instead fix the driver design or bug please.
Hi Stephen,
This is not a Soft NIC driver-specific hack, this is required for working
around some of the ethdev drivers that don't implement the stop() API correctly
and free up the device queues or some other internal resources on stop()
instead of close().
The Soft NIC is a meta-device that sits on top of other "physical" ethdev
devices, so when the Soft NIC device continues to poll the queues of those physical
devices after their queues have been freed, the Soft NIC will get a segfault. This fix is
required to protect against this sort of incorrect driver behavior by simply stopping the
Soft NIC devices first.
We already have several driver specific branches in the test-pmd for e.g. LAG
or virtual devices; IMO this small change falls in the same category and it
should get accepted.
Please let us know if this makes sense to you?
Regards,
Cristian
If the application has to do this then something is wrong with the architecture.
You aren't propagating state changes through in a safe manner.
Other applications will have same issue.
If LAG or virtual devices have similar problems then a generic solution is
needed.
At exit, there is call to stop_packet_forwarding(). Shouldn't that stop SoftNic
from polling of the queues ?
