Add more details to the description of a known issue of PMDs not being
usable when --no-huge EAL command line parameter is used. The issue
actually happens whenever there is a need for physical addresses, even
when there is no PMD attached.
Signed-off-by: Stanislaw Kardach <k...@semihalf.com>
---
doc/guides/rel_notes/known_issues.rst | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/doc/guides/rel_notes/known_issues.rst
b/doc/guides/rel_notes/known_issues.rst
index 570550843a..2e0ffbdd93 100644
--- a/doc/guides/rel_notes/known_issues.rst
+++ b/doc/guides/rel_notes/known_issues.rst
@@ -249,11 +249,15 @@ PMD does not work with --no-huge EAL command line
parameter
-----------------------------------------------------------
**Description**:
- Currently, the DPDK does not store any information about memory allocated
by ``malloc()` (for example, NUMA node,
- physical address), hence PMDs do not work when the ``--no-huge`` command
line parameter is supplied to EAL.
+ Currently, the DPDK does not store any information about memory allocated
by ``malloc()`` (for example, NUMA node,
+ physical address), hence PMDs do not work when the ``--no-huge`` command
line parameter is supplied to EAL. This
+ happens when using non-IOMMU based UIO drivers (i.e. ``igb_uio`` or
``uio_pci_generic``) or when IOVA mode is
+ explicitly set to use physical addresses (via the ``--iova-mode=pa`` EAL
parameter).
**Implication**:
- Sending and receiving data with PMD will not work.
+ Sending and receiving data with PMD will not work. Unit tests checking
``--no-huge`` operation will fail if
+ there is a device bound to the PMD (eal_flags_n_opt_autotest,
eal_flags_no_huge_autotest,
+ eal_flags_vdev_opt_autotest, eal_flags_misc_autotest).
**Resolution/Workaround**:
Use huge page memory or use VFIO to map devices.
--
2.30.2
