Announce that Malicious Driver Detection is not supported. V2: *Rework the words.
Signed-off-by: Wenzhuo Lu <wenzhuo.lu at intel.com> --- doc/guides/nics/ixgbe.rst | 20 ++++++++++++++++++++ doc/guides/rel_notes/release_16_04.rst | 23 +++++++++++++++++++++++ 2 files changed, 43 insertions(+) diff --git a/doc/guides/nics/ixgbe.rst b/doc/guides/nics/ixgbe.rst index 8cae299..7218cdd 100644 --- a/doc/guides/nics/ixgbe.rst +++ b/doc/guides/nics/ixgbe.rst @@ -147,6 +147,26 @@ The following MACROs are used for these three features: * ETH_TXQ_FLAGS_NOXSUMTCP +Malicious Driver Detection not Supported by ixgbe +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The Intel x550 series NICs support a feature called MDD (Malcicious +Driver Detection) which checks the behavior of the VF driver. +If this feature is enabled, the VF must use the advanced context descriptor +correctly and set the CC (Check Context) bit. +DPDK PF doesn't support MDD, but kernel PF does. We may hit problem in this +scenario kernel PF + DPDK VF. If user enables MDD in kernel PF, DPDK VF will +not work. Because kernel PF thinks the VF is malicious. But actually it's not. +The only reason is the VF doesn't act as MDD required. +There's significant performance impact to support MDD. DPDK should check if +the advanced context descriptor should be set and set it. And DPDK has to ask +the info about the header length from the upper layer, because parsing the +packet itself is not acceptale. So, it's too expensive to support MDD. +When using kernel PF + DPDK VF on x550, please make sure using the kernel +driver that disables MDD or can disable MDD. (Some kernel driver can use +this CLI 'insmod ixgbe.ko MDD=0,0' to disable MDD. Some kernel driver disables +it by default.) + Sample Application Notes ~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/doc/guides/rel_notes/release_16_04.rst b/doc/guides/rel_notes/release_16_04.rst index 5786f74..0647896 100644 --- a/doc/guides/rel_notes/release_16_04.rst +++ b/doc/guides/rel_notes/release_16_04.rst @@ -90,6 +90,29 @@ This section should contain new known issues in this release. Sample format: tense. Add information on any known workarounds. +Restriction +----------- + +* **Malicious Driver Detection is not supported by ixgbe** + + The Intel x550 series NICs support a feature called MDD (Malcicious + Driver Detection) which checks the behavior of the VF driver. + If this feature is enabled, the VF must use the advanced context descriptor + correctly and set the CC (Check Context) bit. + DPDK PF doesn't support MDD, but kernel PF does. We may hit problem in this + scenario kernel PF + DPDK VF. If user enables MDD in kernel PF, DPDK VF will + not work. Because kernel PF thinks the VF is malicious. But actually it's not. + The only reason is the VF doesn't act as MDD required. + There's significant performance impact to support MDD. DPDK should check if + the advanced context descriptor should be set and set it. And DPDK has to ask + the info about the header length from the upper layer, because parsing the + packet itself is not acceptale. So, it's too expensive to support MDD. + When using kernel PF + DPDK VF on x550, please make sure using the kernel + driver that disables MDD or can disable MDD. (Some kernel driver can use + this CLI 'insmod ixgbe.ko MDD=0,0' to disable MDD. Some kernel driver disables + it by default.) + + API Changes ----------- -- 1.9.3