From: "Burakov, Anatoly" <anatoly.burakov@intel.com>
To: Thomas Monjalon <thomas@monjalon.net>
Cc: Jerin Jacob Kollanukkaran <jerinj@marvell.com>,
David Marchand <david.marchand@redhat.com>, dev <dev@dpdk.org>,
Ben Walker <benjamin.walker@intel.com>
Subject: Re: [dpdk-dev] [EXT] Re: [PATCH] bus/pci: fix IOVA as VA mode selection
Date: Tue, 9 Jul 2019 16:18:43 +0100 [thread overview]
Message-ID: <9284e5ad-8726-c850-c3a3-a2e0f4d3713e@intel.com> (raw)
In-Reply-To: <2514934.U1Lao15di9@xps>
On 09-Jul-19 4:12 PM, Thomas Monjalon wrote:
> 09/07/2019 17:02, Burakov, Anatoly:
>> When IOMMU is fully enabled (iommu=on at boot time), igb_uio will simply
>> not work. VFIO will work, whichever address mode you use.
>>
>> When IOMMU is in pass-through mode (iommu=pt at boot time), both igb_uio
>> and VFIO will work, although igb_uio will only support IOVA as PA mode.
>> Both modes will enable IOMMU, and both can run in IOVA as PA mode
>> without losing that protection.
>>
>> It's only when IOMMU is off, igb_uio will not engage IOMMU, and VFIO
>> will only work in no-IOMMU mode (thus not engaging IOMMU either), and
>> only then you lack the IOMMU protection.
>
> Could we try to make IOMMU status clear in DPDK logs?
> Then we could check the kernel drivers loaded and give
> a compatibility status for each of them as debug logs.
>
I don't think there is a way to know IOMMU status from DPDK. It's a
property of the system. We can kinda-sorta check IOMMU status if we have
VFIO driver (there's a API to check for vfio_noiommu i think), and we do
log it into debug output, but there is no such facility for igb_uio - we
cannot know if it does or does not engage the IOMMU. (not unless we grep
dmesg or something)
--
Thanks,
Anatoly
prev parent reply other threads:[~2019-07-09 15:18 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-08 14:24 [dpdk-dev] " jerinj
2019-07-08 18:39 ` David Marchand
2019-07-08 19:13 ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-09 8:39 ` Bruce Richardson
2019-07-09 9:05 ` Jerin Jacob Kollanukkaran
2019-07-09 9:32 ` Bruce Richardson
2019-07-09 9:44 ` Burakov, Anatoly
2019-07-09 11:13 ` Jerin Jacob Kollanukkaran
2019-07-09 11:40 ` Burakov, Anatoly
2019-07-09 12:11 ` Jerin Jacob Kollanukkaran
2019-07-09 13:30 ` Burakov, Anatoly
2019-07-09 13:50 ` Burakov, Anatoly
2019-07-09 14:19 ` Jerin Jacob Kollanukkaran
2019-07-09 14:00 ` Jerin Jacob Kollanukkaran
2019-07-09 14:37 ` Burakov, Anatoly
2019-07-09 15:04 ` Thomas Monjalon
2019-07-09 15:06 ` Burakov, Anatoly
2019-07-09 17:50 ` Jerin Jacob Kollanukkaran
2019-07-10 8:09 ` David Marchand
2019-07-09 14:54 ` Burakov, Anatoly
2019-07-09 14:58 ` Jerin Jacob Kollanukkaran
2019-07-09 15:02 ` Burakov, Anatoly
2019-07-09 15:12 ` Thomas Monjalon
2019-07-09 15:18 ` Burakov, Anatoly [this message]
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