DPDK patches and discussions
 help / color / Atom feed
From: "Stojaczyk, Dariusz" <dariusz.stojaczyk@intel.com>
To: Jerin Jacob Kollanukkaran <jerinj@marvell.com>,
	Thomas Monjalon <thomas@monjalon.net>,
	David Marchand <david.marchand@redhat.com>,
	"Burakov, Anatoly" <anatoly.burakov@intel.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH v4 0/4] Fixes on IOVA mode selection
Date: Tue, 23 Jul 2019 04:54:14 +0000
Message-ID: <FBE7E039FA50BF47A673AD0BD3CD56A8464C0631@HASMSX105.ger.corp.intel.com> (raw)
In-Reply-To: <BYAPR18MB242418686A74760374B5EA55C8C70@BYAPR18MB2424.namprd18.prod.outlook.com>

> -----Original Message-----
> From: Jerin Jacob Kollanukkaran [mailto:jerinj@marvell.com]
> Sent: Tuesday, July 23, 2019 6:19 AM
> 
> > -----Original Message-----
> > From: Stojaczyk, Dariusz <dariusz.stojaczyk@intel.com>
> > Sent: Tuesday, July 23, 2019 9:06 AM
> > To: Thomas Monjalon <thomas@monjalon.net>; David Marchand
> > <david.marchand@redhat.com>; Burakov, Anatoly
> > <anatoly.burakov@intel.com>; Jerin Jacob Kollanukkaran
> > <jerinj@marvell.com>
> > Cc: dev@dpdk.org
> > Subject: [EXT] RE: [dpdk-dev] [PATCH v4 0/4] Fixes on IOVA mode selection
> >
> > This introduces a regression where uio-bound devies are attached to a
> DPDK
> > app at runtime.
> 
> Just to understand the requirements;
> # Is this requirement for SPDK?
> # Is brand new PCI device scanned and attached to DPDK at runtime?
> # Any specific reason for using uio vs vfio?

Jerin,

It came up in SPDK tests, but it's certainly nothing SPDK-specific, I can't
give you the steps but it should be reproducible even with testpmd.

The PCI device could have been simply hotplugged to the system after
DPDK app start. DPDK didn't know about it at initialization, so it picked
RTE_IOVA_VA and then would fail to attach any UIO-bound device
ever after:

EAL:   Expecting 'PA' IOVA mode but current mode is 'VA', not initializing
EAL: Driver cannot attach the device (0000:00:09.0)
EAL: Failed to attach device on primary process

UIO is commonly used on systems without IOMMU- including VMs.

> 
> If it is for SPDK,
> # How about introducing rte_eal_init_with_mode(enum rte_iova_mode)?
> # How about adding dummy bus which returns RTE_IOVA_PA in the
> bus_get_iommus_class() in SPDK code base?

There's already an --iova=mode option in DPDK that forces the iova mode.
I'm not concerned about configurability, but the regression in the
default behavior.

I can add workarounds to SPDK, sure, but that wouldn't be a very healthy
approach.

D.

> 
> >
> > When there are no devices attached at initialization, the only safe default
> > should be RTE_IOVA_PA. With RTE_IOVA_VA we just won't be able to do
> > any DMA to uio-bound PCI devices.
> >
> > Can we revert this patch?
> >
> > D.
> >
> > > -----Original Message-----
> > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Thomas
> Monjalon
> > > Sent: Monday, July 22, 2019 5:53 PM
> > > To: David Marchand <david.marchand@redhat.com>; Burakov, Anatoly
> > > <anatoly.burakov@intel.com>; jerinj@marvell.com
> > > Cc: dev@dpdk.org
> > > Subject: Re: [dpdk-dev] [PATCH v4 0/4] Fixes on IOVA mode selection
> > >
> > > 22/07/2019 14:56, David Marchand:
> > > > Following the issues reported by Jerin and the discussion that
> > > > emerged from it, here are fixes to restore and document the behavior
> > > > of the EAL and the pci bus driver.
> > > >
> > > > I pondered all the arguments and tried to have the less changes
> > > > possible.
> > > > I can't find a need for a flag to just announce support of physical
> > > > addresses from the pmd point of view.
> > > > So it ended up with something really close to what Jerin had suggested.
> > > >
> > > > But the problem is that this is still unfinished wrt the documentation.
> > > > I will be offline for 10 days and we need this to move forward, so
> > > > sending anyway.
> > > >
> > > > Changelog since v3:
> > > > - fixed typos in patch 2,
> > > > - updated patch 3 title,
> > > > - moved and reworded comments in the note section in patch 4,
> > > >
> > > > Changelog since v2 (Jerin):
> > > > - Patch 2/4 - Remove personal appeals in log messages(Anatoly)
> > > > - Patch 4/4 - Added documentation (Anatoly)
> > > >
> > > > Changelog since v1 (Jerin):
> > > > - Changed RTE_PCI_DRV_IOVA_AS_VA flag name as
> > > RTE_PCI_DRV_NEED_IOVA_AS_VA
> > > >   (patch 3/4)
> > > > - Changed IOVA mode as VA for default case(patch 4/4) with
> > > documentation
> > > > - Tested the patch series on octeontx2 platform
> > >
> > > Applied, thanks Jerin, Anatoly and David for converging on a
> > > documented solution together.
> > >
> > >


  reply index

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-10 21:48 [dpdk-dev] [PATCH 0/2] " David Marchand
2019-07-10 21:48 ` [dpdk-dev] [PATCH 1/2] Revert "bus/pci: add Mellanox kernel driver type" David Marchand
2019-07-16 10:37   ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-10 21:48 ` [dpdk-dev] [PATCH 2/2] eal: fix IOVA mode selection as VA for pci drivers David Marchand
2019-07-11 14:40   ` Thomas Monjalon
2019-07-12  8:05     ` Jerin Jacob Kollanukkaran
2019-07-12 11:03   ` Burakov, Anatoly
2019-07-12 12:43     ` Thomas Monjalon
2019-07-12 12:58       ` Burakov, Anatoly
2019-07-12 13:19         ` Bruce Richardson
2019-07-15 14:26       ` Jerin Jacob Kollanukkaran
2019-07-15 15:03         ` Thomas Monjalon
2019-07-15 15:35           ` Jerin Jacob Kollanukkaran
2019-07-15 16:06             ` Thomas Monjalon
2019-07-15 16:27               ` Jerin Jacob Kollanukkaran
2019-07-16 13:46 ` [dpdk-dev] [PATCH v2 0/4] Fixes on IOVA mode selection jerinj
2019-07-16 13:46   ` [dpdk-dev] [PATCH v2 1/4] Revert "bus/pci: add Mellanox kernel driver type" jerinj
2019-07-16 13:46   ` [dpdk-dev] [PATCH v2 2/4] eal: fix IOVA mode selection as VA for pci drivers jerinj
2019-07-16 14:26     ` Burakov, Anatoly
2019-07-16 15:07       ` Jerin Jacob Kollanukkaran
2019-07-16 13:46   ` [dpdk-dev] [PATCH v2 3/4] eal: change RTE_PCI_DRV_IOVA_AS_VA flag name jerinj
2019-07-16 13:46   ` [dpdk-dev] [PATCH v2 4/4] eal: select IOVA mode as VA for default case jerinj
2019-07-16 14:33     ` Burakov, Anatoly
2019-07-17  8:33       ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-17 12:38         ` Burakov, Anatoly
2019-07-17 14:04           ` Jerin Jacob Kollanukkaran
2019-07-18  6:45   ` [dpdk-dev] [PATCH v3 0/4] Fixes on IOVA mode selection jerinj
2019-07-18  6:45     ` [dpdk-dev] [PATCH v3 1/4] Revert "bus/pci: add Mellanox kernel driver type" jerinj
2019-07-18  6:45     ` [dpdk-dev] [PATCH v3 2/4] eal: fix IOVA mode selection as VA for pci drivers jerinj
2019-07-18  6:45     ` [dpdk-dev] [PATCH v3 3/4] eal: change RTE_PCI_DRV_IOVA_AS_VA flag name jerinj
2019-07-18  6:45     ` [dpdk-dev] [PATCH v3 4/4] eal: select IOVA mode as VA for default case jerinj
2019-07-22 11:28     ` [dpdk-dev] [PATCH v3 0/4] Fixes on IOVA mode selection David Marchand
2019-07-22 12:56 ` [dpdk-dev] [PATCH v4 " David Marchand
2019-07-22 12:56   ` [dpdk-dev] [PATCH v4 1/4] Revert "bus/pci: add Mellanox kernel driver type" David Marchand
2019-07-22 12:56   ` [dpdk-dev] [PATCH v4 2/4] eal: fix IOVA mode selection as VA for PCI drivers David Marchand
2019-11-25  9:33     ` Ferruh Yigit
2019-11-25 10:22       ` Thomas Monjalon
2019-11-25 12:03         ` Ferruh Yigit
2019-11-25 12:36           ` David Marchand
2019-11-25 12:58             ` Burakov, Anatoly
2019-11-25 14:29               ` Thomas Monjalon
2019-11-25 11:07       ` Jerin Jacob
2019-07-22 12:56   ` [dpdk-dev] [PATCH v4 3/4] drivers: change IOVA as VA PCI flag name David Marchand
2019-07-22 12:56   ` [dpdk-dev] [PATCH v4 4/4] eal: select IOVA as VA mode for default case David Marchand
2019-07-22 15:53   ` [dpdk-dev] [PATCH v4 0/4] Fixes on IOVA mode selection Thomas Monjalon
2019-07-23  3:35     ` Stojaczyk, Dariusz
2019-07-23  4:18       ` Jerin Jacob Kollanukkaran
2019-07-23  4:54         ` Stojaczyk, Dariusz [this message]
2019-07-23  5:27           ` Jerin Jacob Kollanukkaran
2019-07-23  7:21             ` Thomas Monjalon
2019-07-23  9:57             ` Burakov, Anatoly
2019-07-23 10:25               ` Thomas Monjalon
2019-07-23 13:56                 ` Burakov, Anatoly
2019-07-23 14:24                   ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-23 14:29                   ` [dpdk-dev] " Burakov, Anatoly
2019-07-23 14:36                     ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-23 15:47                       ` Burakov, Anatoly

Reply instructions:

You may reply publically 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=FBE7E039FA50BF47A673AD0BD3CD56A8464C0631@HASMSX105.ger.corp.intel.com \
    --to=dariusz.stojaczyk@intel.com \
    --cc=anatoly.burakov@intel.com \
    --cc=david.marchand@redhat.com \
    --cc=dev@dpdk.org \
    --cc=jerinj@marvell.com \
    --cc=thomas@monjalon.net \
    /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

DPDK patches and discussions

Archives are clonable:
	git clone --mirror http://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ http://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev


Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/ public-inbox