On Mon, Nov 14, 2016 at 3:34 PM, Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> wrote: > On Fri, Nov 11, 2016 at 10:44 PM, Mathias Nyman > <mathias.nyman@xxxxxxxxxxxxxxx> wrote: >> On 10.11.2016 13:22, Oliver Neukum wrote: >>> >>> On Thu, 2016-11-10 at 12:09 +0100, Bjørn Mork wrote: >>>> >>>> Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> writes: >>>>> >>>>> On Wed, Nov 9, 2016 at 8:32 PM, Bjørn Mork <bjorn@xxxxxxx> wrote: >>>>>> >>>>>> Oliver Neukum <oneukum@xxxxxxxx> writes: >>>>>> >>>>>>> On Tue, 2016-11-08 at 13:44 -0500, Alan Stern wrote: >>>>>>> >>>>>>>> These problems could very well be caused by running at SuperSpeed >>>>>>>> (USB-3) instead of high speed (USB-2). >>>>> >>>>> >>>>> Yes, it's running at SuperSpeed, on a Kabylake laptop. >>>>> >>>>> It does not have this issue on a Broadwell laptop, also running at >>>>> SuperSpeed. >>>> >>>> >>>> Then I must join Oliver, being very surprised by where in the stack you >>>> attempt to fix the issue. What you write above indicates a problem in >>>> pci bridge or usb host controller, doesn't it? > > Yes, I was totally wrong about that. > >>> >>> >>> Indeed. And this means we need an XHCI specialist. >>> Mathias, we have a failure specific to one implementation of XHCI. >>> >> >> >> Could be related to resume singnalling time. >> Does the xhci fix for it in 4.9-rc3 help? >> >> commit 7d3b016a6f5a0fa610dfd02b05654c08fa4ae514 >> xhci: use default USB_RESUME_TIMEOUT when resuming ports. >> >> It doesn't directly explain why it would work on Broadwell but not Kabylake, >> but it resolved very similar cases. >> >> If not, then adding dynamic debug for xhci could show something. > > I tried the latest commit, 6005a545cadb2adca64350c7aee17d002563e8c7, > on for-usb-next branch. > > Now the cdc_mbim still probe failed at the first time, but somehow it > re-probed again with a success. > > I reverted commit 7d3b016a6f5a0fa610dfd02b05654c08fa4ae514 and the > behavior is the same, first time probed failed, second time probed > success. > > The attached dmesg is with usbcore and xhci_hcd dynamic debug enabled. I filed a bug report on bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=187861 > >> >> -Mathias >> -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
