usb/160436: ucom wedges machine on parity error ?
phk at critter.freebsd.dk
Sat Sep 3 20:00:21 UTC 2011
>Synopsis: ucom wedges machine on parity error ?
>Arrival-Date: Sat Sep 03 20:00:20 UTC 2011
>Originator: Poul-Henning Kamp
>Release: FreeBSD 8.2-STABLE i386
FreeBSD shus.dc.freebsd.dk 8.2-STABLE FreeBSD 8.2-STABLE #0: Wed Aug 31 08:43:34 UTC 2011 root at hex-drift.freebsd.dk:/freebsd/obj/nanobsd.shus/freebsd/src/sys/NET4801 i386
I'm running Soekris NET4801 doing data collection, it has been
running stable for years.
Recently I added a USB-serial port running in raw mode
The machine started freezing hard and recovered only when the
watchdog kicked in.
When frozen, there is no serial console reaction, no packet
traffic and no signs of a panic message.
I tried two different USB-serial dongles, one UPLCOM and
one UFTDI, apart from a possibly slightly different frequency,
Disabling the software on the USB serial port, made the freezes
I have now moved the parity check into software, running the
port as 300/8/NONE instead, and the problem has not been seen
Has anybody ever tested a parity error on a USB serial port ?
More information about the freebsd-usb