X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;ds=sidebyside;f=doc%2Fguides%2Frel_notes%2Fknown_issues.rst;h=f149ac7d0b414043ce275492882a9335983a5984;hb=2b5518b705b6bd5ffbdb24d5df0d70e72b9220c9;hp=3cd423761761227f66e2a177975807d03bd2a715;hpb=a4045ab3778396de7ee0f4975098ee0ee7fa079f;p=dpdk.git

diff --git a/doc/guides/rel_notes/known_issues.rst b/doc/guides/rel_notes/known_issues.rst
index 3cd4237617..f149ac7d0b 100644
--- a/doc/guides/rel_notes/known_issues.rst
+++ b/doc/guides/rel_notes/known_issues.rst
@@ -640,3 +640,60 @@ I40e VF may not receive packets in the promiscuous mode
 
 **Driver/Module**:
    Poll Mode Driver (PMD).
+
+
+uio pci generic module bind failed in X710/XL710/XXV710
+-------------------------------------------------------
+
+**Description**:
+   The ``uio_pci_generic`` module is not supported by XL710, since the errata of XL710
+   states that the Interrupt Status bit is not implemented. The errata is the item #71
+   from the `xl710 controller spec
+   <http://www.intel.com/content/www/us/en/embedded/products/networking/xl710-10-40-controller-spec-update.html>`_.
+   The hw limitation is the same as other X710/XXV710 NICs.
+
+**Implication**:
+   When use ``--bind=uio_pci_generic``, the ``uio_pci_generic`` module probes device and check the Interrupt
+   Status bit. Since it is not supported by X710/XL710/XXV710, it return a *failed* value. The statement
+   that these products don’t support INTx masking, is indicated in the related `linux kernel commit
+   <https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/drivers/pci/quirks.c?id=8bcf4525c5d43306c5fd07e132bc8650e3491aec>`_.
+
+**Resolution/Workaround**:
+   Do not bind the ``uio_pci_generic`` module in X710/XL710/XXV710 NICs.
+
+**Affected Environment/Platform**:
+   All.
+
+**Driver/Module**:
+   Poll Mode Driver (PMD).
+
+
+virtio tx_burst() function cannot do TSO on shared packets
+----------------------------------------------------------
+
+**Description**:
+   The standard TX function of virtio driver does not manage shared
+   packets properly when doing TSO. These packets should be read-only
+   but the driver modifies them.
+
+   When doing TSO, the virtio standard expects that the L4 checksum is
+   set to the pseudo header checksum in the packet data, which is
+   different than the DPDK API. The driver patches the L4 checksum to
+   conform to the virtio standard, but this solution is invalid when
+   dealing with shared packets (clones), because the packet data should
+   not be modified.
+
+**Implication**:
+   In this situation, the shared data will be modified by the driver,
+   potentially causing race conditions with the other users of the mbuf
+   data.
+
+**Resolution/Workaround**:
+   The workaround in the application is to ensure that the network
+   headers in the packet data are not shared.
+
+**Affected Environment/Platform**:
+   Virtual machines running a virtio driver.
+
+**Driver/Module**:
+   Poll Mode Driver (PMD).