Hi Mathias, Il giorno ven 26 lug 2019 alle ore 10:50 Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> ha scritto: > > On 24.7.2019 22.09, Daniele Palmas wrote: > > Hello all, > > > > I've a system with kernel 4.14.127 that is showing unexpected xhci-hcd > > (ASM1042A) errors with a Qualcomm based modem, when running the > > following test: > > > > - signal strength qmi requests looping every few seconds on > > /dev/cdc-wdm (driver qmi_wwan) > > - iperf tcp data connection test on the modem network interface > > > > The issue is showing also with kernel 5.0 > > > > The issues is showing in three different ways: > > > > First one: > > > > 2019-07-24 15:17:45.495293 kern.err kernel:xhci_hcd 0000:03:00.0: > > ERROR Transfer event TRB DMA ptr not part of current TD ep_index 28 > > comp_code 13 > > > > 2019-07-24 15:17:45.495392 kern.warning kernel:xhci_hcd 0000:03:00.0: > > Looking for event-dma 000000007725b420 trb-start 000000007725b400 > > trb-end 000000007725b400 seg-start 000000007725b000 seg-end > > 000000007725bff0 > > The xhci driver expects events for transfers in the same order they were > queued. For some reason we get an event for the transfer block queued at > address b420 before we get events for transfers at b400 and b410. > > xhci traces of a 5.0 kernel would show in more detail what's going on. > can be taken with: > > mount -t debugfs none /sys/kernel/debug > echo 'module xhci_hcd =p' >/sys/kernel/debug/dynamic_debug/control > echo 'module usbcore =p' >/sys/kernel/debug/dynamic_debug/control > echo 81920 > /sys/kernel/debug/tracing/buffer_size_kb > echo 1 > /sys/kernel/debug/tracing/events/xhci-hcd/enable > < reproduce the issue > > Send output of dmesg > Send content of /sys/kernel/debug/tracing/trace > > Note that the trace file can be huge > thanks for the explanation. For 4.14.127 I already gathered traces related to that dmesg (you can find them at https://drive.google.com/open?id=1c-vjusa44UgMzrIjAvpz6HKbxEk1Trw1), but I'll try to get the same info for 5. Thanks, Daniele > -Mathias
