lkml.org 
[lkml]   [2010]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang
    Date
    On maanantai 22 helmikuu 2010 22:12:41 Alan Stern wrote:
    > On Mon, 22 Feb 2010, Matthew Garrett wrote:
    > > On Mon, Feb 22, 2010 at 02:10:33PM -0500, Alan Stern wrote:
    > > > On Mon, 22 Feb 2010, Anssi Hannula wrote:
    > > > > Does this mean a tty interface is ill-suited for the microcode
    > > > > upload, and instead qcserial should use the kernel's generic
    > > > > microcode upload mechanism or the userspace should use libusb to do
    > > > > it?
    > > >
    > > > I don't know. Didn't the old successful code use a tty interface?
    > >
    > > Yes. The kfifo changes have caused some sort of alteration in behaviour.
    > >
    > > > > Any idea what could be causing the hang, then?
    > > >
    > > > No idea, unless it's the device.
    > >
    > > Once the device hangs, it then tends to refuse any input until power
    > > cycled. So it's clearly getting into some sort of undefined state,
    > > though whether that's because it only gets sent half of its firmware
    > > (ie, the hang occurs and as a result the hardware dies) or whether it's
    > > causing the hang by dying is unclear.
    >
    > The latest logs did show all the firmware getting sent -- or at least,
    > they show that as much data was sent by the nonworking driver as by the
    > working driver. So I'd say the device causes the hang by dying,
    > although I don't know where the hang is or why a dead device should
    > cause it.

    When the hang happens, the complete firmware is *not* sent to the device. The
    usbmon log is 10 times smaller:
    http://stuff.onse.fi/gobi2000/gobi-regression2.mon.log
    For reference, here's the hang with usbserial debug=1:
    http://stuff.onse.fi/gobi2000/gobi-regression2.dmesg.log

    The later logs were of runs that did not hang, but did still not work. I added
    descriptions here, in case someone is confused with all the logs (which I
    should've named better): http://stuff.onse.fi/gobi2000/

    But if a device in corrupt state can cause such a hang, then it is likely that
    that is happening here (due to the packet bounding issue described in the
    other messages).

    --
    Anssi Hannula


    \
     
     \ /
      Last update: 2010-02-24 03:37    [W:3.176 / U:0.028 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site