[dpdk-dev] doc/guides/rel_notes: Add known issue for IOMMU attributes read
Checks
Commit Message
Read IOMMU attributes from linux kernle 4.10.0 error.
Cc: stable@dpdk.org
Signed-off-by: Rosen Xu <rosen.xu@intel.com>
---
doc/guides/rel_notes/known_issues.rst | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
Comments
On 14-May-18 11:44 AM, Rosen Xu wrote:
> Read IOMMU attributes from linux kernle 4.10.0 error.
s/kernle/kernel :)
>
> Cc: stable@dpdk.org
>
> Signed-off-by: Rosen Xu <rosen.xu@intel.com>
> ---
> doc/guides/rel_notes/known_issues.rst | 21 +++++++++++++++++++++
> 1 file changed, 21 insertions(+)
>
> diff --git a/doc/guides/rel_notes/known_issues.rst b/doc/guides/rel_notes/known_issues.rst
> index afcc2c4..74876ff 100644
> --- a/doc/guides/rel_notes/known_issues.rst
> +++ b/doc/guides/rel_notes/known_issues.rst
> @@ -714,3 +714,24 @@ igb_uio can not be used when running l3fwd-power
>
> **Driver/Module**:
> ``igb_uio`` module.
> +
> +
> +linux kernel iommu attribute read error
Should this be capitalized?
> +---------------------------------------
> +
> +**Description**:
> + Read immu attributes from /sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap in linux kernel
> + 4.10.0 error. That because the link between the iommu sysfs-device and the struct intel_iommu
> + is no longer stored as driver-data.
s/immu/IOMMU/, and i think this needs to be rewritten to something like
as follows:
Reading IOMMU attributes from
/sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap in Linux kernel
4.10.0 results in an error. This is because the link between the IOMMU
sysfs-device and struct intel_iommu is no longer stored as driver-data.
(i have no idea what that last sentence means, maybe someone could help
provide a better explanation?)
> +
> +**Implication**:
> + When insmod ``vfio-pci`` and running testpmd APP, it doesn't initiate properly.
Should probably be reworded as follows:
When binding devices to VFIO and attempting to run testpmd application,
testpmd (and other DPDK applications) will not initialize.
> +
> +**Resolution/Workaround**:
> + Use other linux kernel version. It only happens in linux kernel 4.10.0.
> +
> +**Affected Environment/Platform**:
> + ALL OS of linux kernel 4.10.0.
> +
> +**Driver/Module**:
> + ``vfio-pci`` module.
>
Hi Anatoly,
> -----Original Message-----
> From: Burakov, Anatoly
> Sent: Tuesday, May 15, 2018 1:10
> To: Xu, Rosen <rosen.xu@intel.com>; dev@dpdk.org
> Cc: gaetan.rivet@6wind.com; Mcnamara, John <john.mcnamara@intel.com>;
> Pei, Yulong <yulong.pei@intel.com>; stable@dpdk.org
> Subject: Re: [PATCH] doc/guides/rel_notes: Add known issue for IOMMU
> attributes read
>
> On 14-May-18 11:44 AM, Rosen Xu wrote:
> > Read IOMMU attributes from linux kernle 4.10.0 error.
>
> s/kernle/kernel :)
Fixed
> >
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Rosen Xu <rosen.xu@intel.com>
> > ---
> > doc/guides/rel_notes/known_issues.rst | 21 +++++++++++++++++++++
> > 1 file changed, 21 insertions(+)
> >
> > diff --git a/doc/guides/rel_notes/known_issues.rst
> > b/doc/guides/rel_notes/known_issues.rst
> > index afcc2c4..74876ff 100644
> > --- a/doc/guides/rel_notes/known_issues.rst
> > +++ b/doc/guides/rel_notes/known_issues.rst
> > @@ -714,3 +714,24 @@ igb_uio can not be used when running l3fwd-
> power
> >
> > **Driver/Module**:
> > ``igb_uio`` module.
> > +
> > +
> > +linux kernel iommu attribute read error
>
> Should this be capitalized?
Fixed
> > +---------------------------------------
> > +
> > +**Description**:
> > + Read immu attributes from /sys/devices/virtual/iommu/dmarXXX/intel-
> iommu/cap in linux kernel
> > + 4.10.0 error. That because the link between the iommu sysfs-device and
> the struct intel_iommu
> > + is no longer stored as driver-data.
>
> s/immu/IOMMU/, and i think this needs to be rewritten to something like as
> follows:
>
> Reading IOMMU attributes from
Fixed
> /sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap in Linux kernel
> 4.10.0 results in an error. This is because the link between the IOMMU sysfs-
> device and struct intel_iommu is no longer stored as driver-data.
>
> (i have no idea what that last sentence means, maybe someone could help
> provide a better explanation?)
This linux kernel issue is fixed, around the 4.10/4.11 timeframe.
commit a7fdb6e648fb10a4174483b5fc4dac9c25bd2093
Author: Joerg Roedel <jroedel@suse.de>
Date: Tue Feb 28 13:57:18 2017 +0100
iommu/vt-d: Fix crash when accessing VT-d sysfs entries
The link between the iommu sysfs-device and the struct
intel_iommu is no longer stored as driver-data. Update the
code to use the new access method.
> > +
> > +**Implication**:
> > + When insmod ``vfio-pci`` and running testpmd APP, it doesn't initiate
> properly.
>
> Should probably be reworded as follows:
>
> When binding devices to VFIO and attempting to run testpmd application,
> testpmd (and other DPDK applications) will not initialize.
Fixed.
> > +
> > +**Resolution/Workaround**:
> > + Use other linux kernel version. It only happens in linux kernel 4.10.0.
> > +
> > +**Affected Environment/Platform**:
> > + ALL OS of linux kernel 4.10.0.
> > +
> > +**Driver/Module**:
> > + ``vfio-pci`` module.
> >
>
>
> --
> Thanks,
> Anatoly
@@ -714,3 +714,24 @@ igb_uio can not be used when running l3fwd-power
**Driver/Module**:
``igb_uio`` module.
+
+
+linux kernel iommu attribute read error
+---------------------------------------
+
+**Description**:
+ Read immu attributes from /sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap in linux kernel
+ 4.10.0 error. That because the link between the iommu sysfs-device and the struct intel_iommu
+ is no longer stored as driver-data.
+
+**Implication**:
+ When insmod ``vfio-pci`` and running testpmd APP, it doesn't initiate properly.
+
+**Resolution/Workaround**:
+ Use other linux kernel version. It only happens in linux kernel 4.10.0.
+
+**Affected Environment/Platform**:
+ ALL OS of linux kernel 4.10.0.
+
+**Driver/Module**:
+ ``vfio-pci`` module.