Weird error messages -- what can be their root cause?

[Gabor LENCSE <lencse@hit.bme.hu>]

Dear All,

I have been using siitperf ( https://github.com/lencsegabor/siitperf ), 
my DPDK-based RFC 8219 SIIT and stateful NAT64 tester under Debian 9 
using DPDK 16 for several years and it worked perfectly.

I have upgraded it to DPDK 21 under Ubuntu 22.04, and it seemed to work.

However it failed under Debian 12 using DPDK 22. Then I tried under 
Debian 11 using DPDK 20.11.7. What I experienced was, that the senders 
functions did not finish sending, and the receiver functions did not 
receive any packets when I did a self-test (the network interfaces were 
looped back with a direct cable). When I sent only a very low number of 
packets, then a sender functions finished, but still no packets arrived.

Here is the dmesg, when I sent only a single frame in each direction:

[ 9475.185898] dmar_fault: 2 callbacks suppressed
[ 9475.185899] DMAR: DRHD: handling fault status reg 302
[ 9475.186851] DMAR: [DMA Read] Request device [01:00.1] PASID ffffffff 
fault addr ffe942000 [fault reason 06] PTE Read access is not set
[ 9475.187730] DMAR: [DMA Read] Request device [01:00.0] PASID ffffffff 
fault addr ffe96b000 [fault reason 06] PTE Read access is not set

Do you have any idea, what the strange messages may mean?

When I send more frames, more messages appear, but their number is not 
proportional to the number of frames per direction. E.g. when I sent 5 
frames per direction, the output was:

[10630.082486] dmar_fault: 2 callbacks suppressed
[10630.082487] DMAR: DRHD: handling fault status reg 302
[10630.083425] DMAR: [DMA Read] Request device [01:00.1] PASID ffffffff 
fault addr ffe942000 [fault reason 06] PTE Read access is not set
[10630.084290] DMAR: [DMA Read] Request device [01:00.0] PASID ffffffff 
fault addr ffe96b000 [fault reason 06] PTE Read access is not set
[10630.282477] DMAR: DRHD: handling fault status reg 502
[10630.283293] DMAR: [DMA Read] Request device [01:00.1] PASID ffffffff 
fault addr ffe942000 [fault reason 06] PTE Read access is not set
[10630.284120] DMAR: [DMA Read] Request device [01:00.0] PASID ffffffff 
fault addr ffe96b000 [fault reason 06] PTE Read access is not set
[10630.482477] DMAR: DRHD: handling fault status reg 702
[10630.483272] DMAR: [DMA Read] Request device [01:00.1] PASID ffffffff 
fault addr ffe942000 [fault reason 06] PTE Read access is not set

I use the same hardware, which worked perfectly under Debian 9. This is 
my NIC:

root@tester:~/siitperf# dpdk-devbind.py --status

Network devices using DPDK-compatible driver
============================================
0000:01:00.0 'Ethernet Controller 10-Gigabit X540-AT2 1528' 
drv=uio_pci_generic unused=ixgbe
0000:01:00.1 'Ethernet Controller 10-Gigabit X540-AT2 1528' 
drv=uio_pci_generic unused=ixgbe

And my kernel command line is:

root@tester:~/siitperf# cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-5.10.0-25-amd64 
root=UUID=2825291f-1f01-4cd3-9f03-ddbaa24c773e ro quiet idle=poll 
isolcpus=1-15 hugepagesz=1G hugepages=32

Any suggestions are appreciated!

Thank you very much for your help in advance!

Best regards,

Gábor