RE: [EXT] [dpdk-dev v1] lib/cryptodev: multi-process IPC request handler

From: Akhil Goyal <gakhil@marvell.com>
To: "Zhang, Roy Fan" <roy.fan.zhang@intel.com>,
	"Ji, Kai" <kai.ji@intel.com>,  "dev@dpdk.org" <dev@dpdk.org>
Cc: Anoob Joseph <anoobj@marvell.com>,
	"hemant.agrawal@nxp.com" <hemant.agrawal@nxp.com>,
	Chandubabu Namburu <chandu@amd.com>,
	Ruifeng Wang <ruifeng.wang@arm.com>,
	"ajit.khaparde@broadcom.com" <ajit.khaparde@broadcom.com>,
	Michael Shamis <michaelsh@marvell.com>,
	Nagadheeraj Rottela <rnagadheeraj@marvell.com>,
	"matan@nvidia.com" <matan@nvidia.com>,
	Jay Zhou <jianjay.zhou@huawei.com>
Subject: RE: [EXT] [dpdk-dev v1] lib/cryptodev: multi-process IPC request handler
Date: Mon, 8 Aug 2022 07:43:14 +0000	[thread overview]
Message-ID: <CO6PR18MB44842B4E34A44B6BA62AA563D8639@CO6PR18MB4484.namprd18.prod.outlook.com> (raw)
In-Reply-To: <MW5PR11MB5809C6C05A0A10FF92DBA0FFB89E9@MW5PR11MB5809.namprd11.prod.outlook.com>

Hi Fan,
> Hi Akhil,
> 
> > This is a library change you should cc all PMD owners while sending patch.
> Kai is in holiday at the moment and will be back in a week. I will sync with him
> then.
> >
> > > This patch add in multi-process IPC request handler function in rte
> > > cryptodev. This function intend to support a queue-pair configuration
> > > request to allow the secondary process to reconfigure the queue-pair
> > > setup'ed by the primary process.
> >
> > Who will release the queue pair already setup by primary in the first place?
> 
> Fan: If the queue pair already setup by primary the secondary shall not recreate
> it
> but use it instead.

OK but the description says secondary would reconfigure the qp setup by primary.

> 
> > Currently, all queues are setup by primary and secondary uses them.
> > So if a queue is re-initialized by secondary, and if it is being used in primary
> > process,
> > Wont that drop packets abruptly if the queue is re-initialized?
> 
> You are right. What about creating a variable in the queue pair with either PID
> or thread id who own the queue pair?

I believe we should not expose the PID/thread id via queue to the user application.
This may be security issue.

Instead an "in_use" parameter can be added which can tell if sone other process is using it or not.
And this in_use param also need not be exposed to user. It can be completely hidden in the PMD.
User will get an error number(probably -EUSERS) indicating the queue pair is already in use.

Regards,
Akhil