Hi Harini, On 01.08.2018 15:53, Harini Katakam wrote: > Hi Jennifer, > > On Tue, Jun 5, 2018 at 10:21 AM, Harini Katakam <[email protected]> wrote: >> Hi Jeniffer, >> >> On Mon, Jun 4, 2018 at 8:35 PM, Nicolas Ferre >> <[email protected]> wrote: >>> Jennifer, >>> >>> On 25/05/2018 at 23:44, Jennifer Dahm wrote: >>>> >>>> During testing, I discovered that the Zynq GEM hardware overwrites all >>>> outgoing UDP packet checksums, which is illegal in packet forwarding >>>> cases. This happens both with and without the checksum-zeroing >>>> behavior introduced in 007e4ba3ee137f4700f39aa6dbaf01a71047c5f6 >>>> ("net: macb: initialize checksum when using checksum offloading"). The >>>> only solution to both the small packet bug and the packet forwarding >>>> bug that I can find is to disable TX checksum offloading entirely. >>> >>> >> >> Thanks for the extensive testing. >> I'll try to reproduce and see if it is something to be fixed in the driver. >> >>> Are the bugs listed above present in all revisions of the GEM IP, only for >>> some revisions? >>> Is there an errata that describe this issue for the Zynq GEM? >> >> @Nicolas, AFAIK, there is no errata for this in either Cadence or >> Zynq documentation. > > I was unable to reproduce this issue on Zynq. > Although I do not have HW with two GEM ports, > I tried by routing one GEM via PL and another via on board RGMII. > Since there was no specific errata related to this, I also tried on > subsequent ZynqMP versions with multiple GEM ports but dint find any > checksum issues. I discussed the same with cadence and they > tried the test with 2 bytes of UDP payload on the Zynq GEM IP > version in their regressions and did not hit any issue either. > > I tried to reach out earlier to see if you can share your exact > application. Could you please let me know if you have any > further updates?
I manage to reproduce the issue and provide a patch for this (see patch 3/3 from [1]). [1] https://www.spinics.net/lists/netdev/msg513848.html > > Regards, > Harini >
