DPDK patches and discussions
 help / color / mirror / Atom feed
From: Tiwei Bie <tiwei.bie@intel.com>
To: David Marchand <david.marchand@redhat.com>
Cc: dev <dev@dpdk.org>, Maxime Coquelin <maxime.coquelin@redhat.com>,
	Zhihong Wang <zhihong.wang@intel.com>
Subject: Re: [dpdk-dev] [PATCH 2/2] net/virtio: do not require IO permissions
Date: Fri, 18 Oct 2019 18:05:14 +0800	[thread overview]
Message-ID: <20191018100514.GA6862@___> (raw)
In-Reply-To: <CAJFAV8zj+yios+82=S_QYWQGZd8NfgQi7j_ppB=aogCN69x4Kw@mail.gmail.com>

On Fri, Oct 18, 2019 at 10:33:47AM +0200, David Marchand wrote:
> On Fri, Oct 18, 2019 at 10:19 AM Tiwei Bie <tiwei.bie@intel.com> wrote:
> > On Thu, Oct 17, 2019 at 01:56:28PM +0200, David Marchand wrote:
> > > On x86, iopl permissions are only needed when the virtio devices are
> > > bound to a uio kernel module.
> > >
> > > When running a dpdk application as non root, the virtio driver was
> > > refusing to register because of this check while it could work when
> > > binding the device to vfio (requires to have a vIOMMU configured).
> > >
> > > We still need to call rte_eal_iopl_init() in the constructor so that
> > > the interrupt thread would inherit this permission in the case it could
> > > be used with UIO later.
> > > Log a warning message for the user to understand what is wrong.
> > >
> > > Signed-off-by: David Marchand <david.marchand@redhat.com>
> > > ---
> > >  drivers/net/virtio/virtio_ethdev.c | 8 ++------
> > >  1 file changed, 2 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
> > > index 7261109..3506ca0 100644
> > > --- a/drivers/net/virtio/virtio_ethdev.c
> > > +++ b/drivers/net/virtio/virtio_ethdev.c
> > > @@ -1995,11 +1995,6 @@ exit:
> > >  static int eth_virtio_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
> > >       struct rte_pci_device *pci_dev)
> > >  {
> > > -     if (rte_eal_iopl_init() != 0) {
> > > -             PMD_INIT_LOG(ERR, "IOPL call failed - cannot use virtio PMD");
> > > -             return 1;
> > > -     }
> > > -
> > >       /* virtio pmd skips probe if device needs to work in vdpa mode */
> > >       if (vdpa_mode_selected(pci_dev->device.devargs))
> > >               return 1;
> > > @@ -2031,7 +2026,8 @@ static struct rte_pci_driver rte_virtio_pmd = {
> > >
> > >  RTE_INIT(rte_virtio_pmd_init)
> > >  {
> > > -     rte_eal_iopl_init();
> > > +     if (rte_eal_iopl_init() != 0)
> > > +             PMD_INIT_LOG(WARNING, "IOPL call failed - virtio devices won't be functional if bound to UIO drivers");
> >
> > Basically this will undo what below commit did, i.e.
> > annoying log will show again.
> >
> > https://github.com/DPDK/dpdk/commit/705dced4a72a1053368c84c4b68f04f028a78b30
> 
> Yes.. true.
> I wanted to keep a trace for debug, so maybe lower this to debug
> level, or just drop this message.
> 
> 
> >
> > Maybe it's better to print this error when we really
> > need the port IO (legacy device):
> 
> virtio calls rte_pci_ioport_map, so I suppose we can change the log
> level to ERR in the first patch of this series:
> http://patchwork.dpdk.org/patch/61370/
> 
> And I suppose I could add some context in this log, like the device name.

Sounds like a good idea to me.

Thanks,
Tiwei


> 
> >
> > https://github.com/DPDK/dpdk/blob/31b798a6f08e9b333b94b8bb26910209aa810b73/drivers/net/virtio/virtio_pci.c#L679-L680
> > https://github.com/DPDK/dpdk/blob/31b798a6f08e9b333b94b8bb26910209aa810b73/drivers/net/virtio/virtio_ethdev.c#L1834-L1835
> 
> 
> -- 
> David Marchand

  reply	other threads:[~2019-10-18 10:08 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-17 11:56 [dpdk-dev] [PATCH 0/2] Using virtio ethdev ports as non-root David Marchand
2019-10-17 11:56 ` [dpdk-dev] [PATCH 1/2] bus/pci: check IO permissions for UIO only David Marchand
2019-10-17 11:56 ` [dpdk-dev] [PATCH 2/2] net/virtio: do not require IO permissions David Marchand
2019-10-18  8:16   ` Tiwei Bie
2019-10-18  8:33     ` David Marchand
2019-10-18 10:05       ` Tiwei Bie [this message]
2019-10-20 12:29 ` [dpdk-dev] [PATCH v2 0/2] Using virtio ethdev ports as non-root David Marchand
2019-10-20 12:29   ` [dpdk-dev] [PATCH v2 1/2] bus/pci: check IO permissions for UIO only David Marchand
2019-10-20 12:29   ` [dpdk-dev] [PATCH v2 2/2] net/virtio: do not require IO permissions David Marchand
2019-10-21 13:10   ` [dpdk-dev] [PATCH v2 0/2] Using virtio ethdev ports as non-root Maxime Coquelin
2019-10-22  8:21 ` [dpdk-dev] [PATCH v3 " David Marchand
2019-10-22  8:21   ` [dpdk-dev] [PATCH v3 1/2] bus/pci: check IO permissions for UIO only David Marchand
2019-10-24  9:55     ` Maxime Coquelin
2019-10-22  8:21   ` [dpdk-dev] [PATCH v3 2/2] net/virtio: do not require IO permissions David Marchand
2019-10-23  4:56     ` Tiwei Bie
2019-10-25 10:11   ` [dpdk-dev] [PATCH v3 0/2] Using virtio ethdev ports as non-root David Marchand

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191018100514.GA6862@___ \
    --to=tiwei.bie@intel.com \
    --cc=david.marchand@redhat.com \
    --cc=dev@dpdk.org \
    --cc=maxime.coquelin@redhat.com \
    --cc=zhihong.wang@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).