On Mon, Aug 10, 2009 at 08:51:15PM +0200, Bruno Prémont wrote: > On Mon, 10 August 2009 Bruno Prémont <bonbons@xxxxxxxxxxxxxxxxx> wrote: > > On Mon, 10 August 2009 Greg KH <greg@xxxxxxxxx> wrote: > > > On Mon, Aug 10, 2009 at 07:18:22PM +0200, Bruno Prémont wrote: > > > > On Mon, 10 August 2009 Greg KH <greg@xxxxxxxxx> wrote: > > > > > On Mon, Aug 10, 2009 at 11:18:29AM -0400, Alan Stern wrote: > > > > > > On Sat, 8 Aug 2009, Bruno Prémont wrote: > > > > > > > > > > > > > I tried bisecting this but bisect did end up on a fully > > > > > > > unrelated commit (which is not even being compiled into my > > > > > > > kernel). Possibly the failed bisect could be related to > > > > > > > mis-classified kernel panic/hang while pulling the USB cable > > > > > > > (there were two such panics for the whole iteration)? > > > > > > > > > > > > > > There are quite a few patches touching tty, ttyUSB and > > > > > > > friends between rc4 and now so pretty hard to guess on the > > > > > > > correct one. > > > > > > > > > > > > > > The oops always happens when I disconnect the USB serial > > > > > > > console (here the one built into Marvell SheevaPlug) while > > > > > > > having minicom connected to it. > > > > > > > During the bisection for the last few bad iterations minicom > > > > > > > got killed (segfault), the bad ones on the iteration left a > > > > > > > minicom zombie in 'D' state. > > > > > > Ok, a few questions. > > > > > > Are you pulling the device out when you have a console attached to > > > the device, or just a "normal" minicom connection with it? I can't > > > seem to duplicate this here at the moment for some reason :( > > > > > > thanks, > > > > > > greg k-h > > > > > > > The SheevaPlug has a getty running on ttyS0 (agetty 115200 ttyS0 > > vt100). That ttyS0 is exported via the FTDI USB to Serial+JTag > > converter. > > > > On the laptop side (where the kernel Oopses) I see /dev/ttyUSB0 (which > > I instruct minicom to use via symlink to > > /dev/serial/by-id/usb-_SheevaPlug_JTAGKey_FT2232D_B_FTS55QK6-if01-port0 -- minicom is > > limited to 63byte length for path to tty device) > > > > I run minicom with the following parameters: > > minicom -o -c on sheeva > > > > /etc/minicom/minirc.sheeva > > pu port /etc/minicom/tty-sheeva > > pu rtscts No > > > > That is 115200 8N1, with neither hardware nor software flow control. > > > > I'm pulling the USB cable while minicom is running and agetty on the > > other side is waiting for password input. (pulling the USB cable is > > too easy - and same effect is obtained when pulling power from the > > SheevaPlug) > > > > > > I have not tried yet with a different USB serial device but will do so > > soon to see if I can reproduce it there. (the other USBSerial device I > > have is: 067b:2303 Prolific Technology, Inc. PL2303 Serial Port) > > I can't reproduce with this one. > > Similar setup, but instead of SheevaPlug (with it's kernel started with > console=ttyS0,115200 + agetty run by init) I just started agetty (same > parameters) on a x86 box with uart serial port (e.g. that x86 kernel > does not have console kernel parameter) and connected that one via > NullModem cable to the Prolific USBSerial converter. > > In this case, no matter how often I pull the USBSerial converter there > is no Oops. > > So it must be something that FTDI driver does differently from e.g. > Prolific one. Ok, thanks, I'll dig through my big box of usb devices to try to find a ftdi device, I was testing this out on a pl2303 device, which is why I couldn't reproduce it it seems. greg k-h -- 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
