Hi, Looks like event for Transfer block (TRB) at 0x32a21060 was never completed, or at least not handled by xhci driver. (either the event was never issued by hw, or something got messed up in the driver along the way)
HC doesn't look busted, it continues sending transfer completions events. it is already at event 0x32a211d0, which is 23 TRBS later. (one TRB is 0x10) This small log sinppet doesnt' say much about the reasons. Can you enable tracing for xhci and send me the output. Instructions: mount -t debugfs none /sys/kernel/debug echo 81920 > /sys/kernel/debug/tracing/buffer_size_kb echo 1 > /sys/kernel/debug/tracing/events/xhci-hcd/enable after issue is triggered, copy and send me the trace file: /sys/kernel/debug/tracing/trace It will be huge -Mathias On 18.05.2018 13:06, Sudip Mukherjee wrote:
Hi Mathias, We are using an Intel Atom based board and the usb controller is: 00:14.0 USB Controller: Intel Corporation Device 0f35 (rev 11) (prog-if 30) Flags: bus master, medium devsel, latency 0, IRQ 130 Memory at df7e0000 (64-bit, non-prefetchable) [size=64K] Capabilities: [70] Power Management version 2 Capabilities: [80] Message Signalled Interrupts: Mask- 64bit+ Queue=0/3 Enable+ Kernel driver in use: xhci_hcd Occassionally we are seeing that the dmesg is flooded with errors like: [ 607.763965] xhci_hcd 0000:00:14.0: WARN Event TRB for slot 8 ep 5 with no TDs queued? [ 607.764968] xhci_hcd 0000:00:14.0: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 5 comp_code 1 [ 607.764976] xhci_hcd 0000:00:14.0: Looking for event-dma 0000000032a211d0 trb-start 0000000032a21060 trb-end 0000000032a21060 seg-start 0000000032a21000 seg-end 0000000032a21ff0 We are using v4.14.2 kernel and I have also applied: e4ec40ec4b26 ("xhci: Don't show incorrect WARN message about events for empty rings") on top of it. The code says "HC is busted, give up!". Should I really give up or something can be done at this point? Will really your appreciate your help in this. -- Regards Sudip
-- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html