On Osage boards, the implementation of the ``rte_delay_us()`` function must be changed to not use the HPET timer.
**Resolution/Workaround**:
- This can be addressed by building the system with the ``CONFIG_RTE_LIBEAL_USE_HPET=n``
- configuration option or by using the ``--no-hpet`` EAL option.
+ This can be addressed by building the system with ``RTE_LIBEAL_USE_HPET`` unset
+ or by using the ``--no-hpet`` EAL option.
**Affected Environment/Platform**:
The Osage customer reference platform.
work correctly, provided the BIOS supports HPET.
**Driver/Module**:
- ``lib/librte_eal/common/include/rte_cycles.h``
+ ``lib/librte_eal/include/rte_cycles.h``
Not all variants of supported NIC types have been used in testing
**Description**:
X710/XL710/XXV710 NICs lack support for indicating INTx is asserted via the interrupt
- bit in the PCI status register. Linux delected them from INTx support table. The related
+ bit in the PCI status register. Linux deleted them from INTx support table. The related
`commit <https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/drivers/pci/quirks.c?id=8bcf4525c5d43306c5fd07e132bc8650e3491aec>`_.
**Implication**:
**Description**:
When VT-d is enabled (``iommu=pt intel_iommu=on``), reading IOMMU attributes from
/sys/devices/virtual/iommu/dmarXXX/intel-iommu/cap on Linux kernel 4.10.0 error.
- This bug is fixed in `Linux commmit a7fdb6e648fb
+ This bug is fixed in `Linux commit a7fdb6e648fb
<https://patchwork.kernel.org/patch/9595727/>`_,
- This bug is introduced in `Linux commmit 39ab9555c241
+ This bug is introduced in `Linux commit 39ab9555c241
<https://patchwork.kernel.org/patch/9554403/>`_,
**Implication**:
**Description**:
``AVX-512`` support has been disabled on some conditions.
- This shouldn't be confused with ``CONFIG_RTE_ENABLE_AVX512`` config option which is already
- disabled by default. This config option defines if ``AVX-512`` specific implementations of
- some file to be used or not. What has been disabled is compiler feature to produce ``AVX-512``
- instructions from any source code.
On DPDK v18.11 ``AVX-512`` is disabled for all ``GCC`` builds which reported to cause a performance
drop.
On DPDK v19.02 ``AVX-512`` disable scope is reduced to ``GCC`` and ``binutils version 2.30`` based
- on information accured from the GCC community defect.
+ on information accrued from the GCC community defect.
**Reason**:
Generated ``AVX-512`` code cause crash:
**Driver/Module**:
ALL.
+
+
+Unsuitable IOVA mode may be picked as the default
+-------------------------------------------------
+
+**Description**
+ Not all kernel drivers and not all devices support all IOVA modes. EAL will
+ attempt to pick a reasonable default based on a number of factors, but there
+ may be cases where the default may be unsuitable (for example, hotplugging
+ devices using `igb_uio` driver while having picked IOVA as VA mode on EAL
+ initialization).
+
+**Implication**
+ Some devices (hotplugged or otherwise) may not work due to incompatible IOVA
+ mode being automatically picked by EAL.
+
+**Resolution/Workaround**:
+ It is possible to force EAL to pick a particular IOVA mode by using the
+ `--iova-mode` command-line parameter. If conflicting requirements are present
+ (such as one device requiring IOVA as PA and one requiring IOVA as VA mode),
+ there is no workaround.
+
+**Affected Environment/Platform**:
+ Linux.
+
+**Driver/Module**:
+ ALL.
+
+Vhost multi-queue reconnection failed with QEMU version >= 4.2.0
+----------------------------------------------------------------
+
+**Description**
+ It's a QEMU regression bug (bad commit: c6beefd674ff). QEMU only saves
+ acked features for one vhost-net when vhost quits. When vhost reconnects
+ to virtio-net/virtio-pmd in multi-queue situations, the features been
+ set multiple times are not consistent.
+
+**Implication**
+ Vhost cannot reconnect back to virtio-net/virtio-pmd normally.
+
+**Resolution/Workaround**:
+ It is possible to filter the incorrect acked features at vhost-user side.
+
+**Affected Environment/Platform**:
+ ALL.
+
+**Driver/Module**:
+ Virtual Device Poll Mode Driver (PMD).