Re: [PATCH rdma-next v1 14/15] RDMA/core: Allow port_groups to be used with namespaces

From: Jason Gunthorpe <jgg@nvidia.com>
To: Parav Pandit <parav@nvidia.com>
Cc: Leon Romanovsky <leon@kernel.org>,
	Doug Ledford <dledford@redhat.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Kees Cook <keescook@chromium.org>,
	Nathan Chancellor <nathan@kernel.org>,
	Adit Ranadive <aditr@vmware.com>,
	Ariel Elior <aelior@marvell.com>,
	Christian Benvenuti <benve@cisco.com>,
	"clang-built-linux@googlegroups.com" 
	<clang-built-linux@googlegroups.com>,
	Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>,
	Devesh Sharma <devesh.sharma@broadcom.com>,
	Gal Pressman <galpress@amazon.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
	Michal Kalderon <mkalderon@marvell.com>,
	Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>,
	Mustafa Ismail <mustafa.ismail@intel.com>,
	Naresh Kumar PBS <nareshkumar.pbs@broadcom.com>,
	Nelson Escobar <neescoba@cisco.com>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Potnuri Bharat Teja <bharat@chelsio.com>,
	Selvin Xavier <selvin.xavier@broadcom.com>,
	Shiraz Saleem <shiraz.saleem@intel.com>,
	VMware PV-Drivers <pv-drivers@vmware.com>,
	Yishai Hadas <yishaih@nvidia.com>,
	Zhu Yanjun <zyjzyj2000@gmail.com>
Subject: Re: [PATCH rdma-next v1 14/15] RDMA/core: Allow port_groups to be used with namespaces
Date: Mon, 7 Jun 2021 20:32:02 -0300	[thread overview]
Message-ID: <20210607233202.GU1002214@nvidia.com> (raw)
In-Reply-To: <PH0PR12MB5481C3DE73C097E938B4E5D1DC389@PH0PR12MB5481.namprd12.prod.outlook.com>

On Mon, Jun 07, 2021 at 01:29:58PM +0000, Parav Pandit wrote:
> 
> 
> > From: Leon Romanovsky <leon@kernel.org>
> > Sent: Monday, June 7, 2021 1:48 PM
> > 
> > From: Jason Gunthorpe <jgg@nvidia.com>
> > 
> > Now that the port_groups data is being destroyed and managed by the core
> > code this restriction is no longer needed. All the ib_port_attrs are compatible
> > with the core's sysfs lifecycle.
> > 
> > Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> > Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
> >  drivers/infiniband/core/device.c | 10 ++++------
> > drivers/infiniband/core/sysfs.c  | 17 ++++++-----------
> >  2 files changed, 10 insertions(+), 17 deletions(-)
> > 
> > diff --git a/drivers/infiniband/core/device.c
> > b/drivers/infiniband/core/device.c
> > index 2cbd77933ea5..92f224a97481 100644
> > +++ b/drivers/infiniband/core/device.c
> > @@ -1698,13 +1698,11 @@ int ib_device_set_netns_put(struct sk_buff
> > *skb,
> >  	}
> > 
> >  	/*
> > -	 * Currently supported only for those providers which support
> > -	 * disassociation and don't do port specific sysfs init. Once a
> > -	 * port_cleanup infrastructure is implemented, this limitation will be
> > -	 * removed.
> > +	 * All the ib_clients, including uverbs, are reset when the namespace
> > is
> > +	 * changed and this cannot be blocked waiting for userspace to do
> > +	 * something, so disassociation is mandatory.
> >  	 */
> > -	if (!dev->ops.disassociate_ucontext || dev->ops.port_groups ||
> > -	    ib_devices_shared_netns) {

So this is OK since we have the clean up now

> > +	if (!dev->ops.disassociate_ucontext || ib_devices_shared_netns) {
> >  		ret = -EOPNOTSUPP;
> >  		goto ns_err;
> >  	}
> > diff --git a/drivers/infiniband/core/sysfs.c b/drivers/infiniband/core/sysfs.c
> > index 09a2e1066df0..f42034fcf3d9 100644
> > +++ b/drivers/infiniband/core/sysfs.c
> > @@ -1236,11 +1236,9 @@ static struct ib_port *setup_port(struct
> > ib_core_device *coredev, int port_num,
> >  	ret = sysfs_create_groups(&p->kobj, p->groups_list);
> >  	if (ret)
> >  		goto err_del;
> > -	if (is_full_dev) {
> > -		ret = sysfs_create_groups(&p->kobj, device-
> > >ops.port_groups);
> > -		if (ret)
> > -			goto err_groups;
> > -	}
> > +	ret = sysfs_create_groups(&p->kobj, device->ops.port_groups);
> > +	if (ret)
> > +		goto err_groups;
> 
> This will expose counters in all net namespaces in shared mode
> (default case).  Application running in one net namespace will be
> able to monitor counters of other net namespace.  This should be
> avoided.

And you want this to stay blocked because the port_groups mostly
contain counters?

Jason