1

I am using Ubuntu 14.04,

ubuntu-14 3.13.0-74-generic #118-Ubuntu SMP Thu Dec 17 22:52:10 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

For the past couple of days I am having problems related to libusb bulk transfers ( async ). When the debug prints are enabled from libusb, I could see more packets ( example 5 packets each 163840 bytes ) were received by libusb. However, the callback was called only once ( example only 163840 bytes ) were received by the application using libsub.

We are seeing this issue only past fews days and computers that has latest kernel updates. For example computers that did not update or kernel dated July 2015 or Jan 2105 are still working.

Today I upgraded Linux kernel to 3.19 to test but no difference. With 3.19 kernel I goet following message in dmesg,

[14720.137271] xhci_hcd 0000:08:00.0: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 4 comp_code 1
[14720.137282] xhci_hcd 0000:08:00.0: Looking for event-dma 00000000b25bd400 trb-start 00000000b25bd2d0 trb-end 00000000b25bd360 seg-start 00000000b25bd000 seg-end 00000000b25bdff0
[14720.138698] xhci_hcd 0000:08:00.0: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 4 comp_code 1
[14720.138706] xhci_hcd 0000:08:00.0: Looking for event-dma 00000000b25bd4a0 trb-start 00000000b25bd2d0 trb-end 00000000b25bd360 seg-start 00000000b25bd000 seg-end 00000000b25bdff0
[14720.140146] xhci_hcd 0000:08:00.0: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 4 comp_code 1
[14720.140155] xhci_hcd 0000:08:00.0: Looking for event-dma 00000000b25bd540 trb-start 00000000b25bd2d0 trb-end 00000000b25bd360 seg-start 00000000b25bd000 seg-end 00000000b25bdff0
[14720.140188] xhci_hcd 0000:08:00.0: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 4 comp_code 13
[14720.140192] xhci_hcd 0000:08:00.0: Looking for event-dma 00000000b25bd550 trb-start 00000000b25bd2d0 trb-end 00000000b25bd360 seg-start 00000000b25bd000 seg-end 00000000b25bdff0

Do you see any possible conflicts, with latest Kernels and libusb (especially for USB 3.0)? Have anyone seen similar issues recently ?

  • When I reduced the bulk request to 16K then the application ( wiht libusb ) seems to work, but the problem in only when submit morethan 16KB of date in my case it is 160KB. Note that this large buffer submission worked until few weeks back. – Dinesh Jan 4 '16 at 14:50
  • Sounds like a bug which you should report possibly – Thomas Ward Jan 11 '16 at 13:04

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.