On Sun, 12 Jun 2011, Hans Petter Selasky wrote:
On Saturday 11 June 2011 23:43:11 Charles Sprickman wrote:
Hello,
We ran into an odd problem last week with our serial consoles after moving
the USB to serial adapters from an old 4.11 box to a box running 8.1. We
have two boxes that incorporate (I assume) hubs and a bunch of FTDI serial
interfaces. One has 16 ports, the other 8. Each is plugged directly into
a USB port on the rear of the mainboard. We run conserver[1] to handle
access to the serial ports. From what I've observed, this application
opens the ports when the daemon starts - it logs any output (handy for
panics, or anything else that might spit interesting info to the console)
and waits for clients to connect to it.
Everything had been working fine for a few weeks. The box was rebooted
recently to enable PostgreSQL to start normally (bumped SHM stuff in
loader.conf). After six days, we found that the consoles were
unresponsive. Restarting conserver brought us this each time we
connected to a console for full read/write access:
[Thu Jun 9 10:04:59 2011] conserver (50113): ERROR: [h22]
open(/dev/ttyU4): Interrupted system call: forcing down
[Thu Jun 9 10:04:59 2011] conserver (50112): ERROR: [h21]
open(/dev/ttyU11): Interrupted system call: forcing down
All devices still appeared in /dev. Stopping conserver and confirming it
and all child processes were gone and then using picocom and cu yielded no
response on the serial ports.
We also found (after the fact) that around the time the consoles became
unresponsive, cpu usage went to nearly 90% and was mostly in the kernel
process intr:
root 12 70.5 0.0 0 136 ?? WL Fri12AM 120:01.47 [intr]
A graph showing cpu usage (red is system):
http://i.imgur.com/0yO5l.png
I should note that we know the cpu spike and devices becoming unresponsive
can be correlated because one of the serial ports runs a temperature
monitor which is tied into our monitoring. When the data goes stale, we
get notified.
Issuing a usbconfig -u 0 reset caused all devices except for the root
hub to disappear and not come back. CPU usage also dipped a bit after
that. Rebooting was the only way to resolve the issue - perhaps plugging
and unplugging would have worked, but that's a bit too complex for our
remote hands.
I can supply full dmesg and more, but for now, here's a summary of the usb
info from dmesg:
FreeBSD 8.1-RELEASE #7: Wed Dec 22 00:49:50 EST 2010
ohci0: OHCI (generic) USB controller mem 0xfe9fc000-0xfe9fcfff irq 10 at
device 15.2 on pci0
ohci0: [ITHREAD]
...
usbus0: OHCI (generic) USB controller on ohci0
usbus0: 12Mbps Full Speed USB v1.0
ugen0.1: (0x1166) at usbus0
...
uhub0: (0x1166) OHCI root HUB, class 9/0, rev 1.00/1.00, addr 1 on
usbus0
uhub0: 4 ports with 4 removable, self powered
ugen0.2: vendor 0x05e3 at usbus0
uhub1: vendor 0x05e3 USB Hub, class 9/0, rev 1.01/0.11, addr 2 on usbus0
uhub1: 7 ports with 7 removable, self powered
ugen0.3: FTDI at usbus0
uftdi0: USB FAST SERIAL ADAPTER on usbus0
uftdi1: USB FAST SERIAL ADAPTER on usbus0
ugen0.4: FTDI at usbus0
uftdi2: USB FAST SERIAL ADAPTER on usbus0
uftdi3: USB FAST SERIAL ADAPTER on usbus0
ugen0.5: FTDI at usbus0
uftdi4: USB FAST SERIAL ADAPTER on usbus0
uftdi5: USB FAST SERIAL ADAPTER on usbus0
ugen0.6: FTDI at usbus0
uftdi6: USB FAST SERIAL ADAPTER on usbus0
uftdi7: USB FAST SERIAL ADAPTER on usbus0
ugen0.7: FTDI at usbus0
uftdi8: USB FAST SERIAL ADAPTER on usbus0
uftdi9: USB FAST SERIAL ADAPTER on usbus0
ugen0.8: FTDI at usbus0
uftdi10: USB FAST SERIAL ADAPTER on usbus0
uftdi11: USB FAST SERIAL ADAPTER on usbus0
ugen0.9: vendor 0x05e3 at usbus0
uhub2: vendor 0x05e3 USB Hub, class 9/0, rev 1.01/0.12, addr 9 on usbus0
uhub2: 4 ports with 4 removable, self powered
ugen0.10: FTDI at usbus0
uftdi12: USB FAST SERIAL ADAPTER on usbus0
uftdi13: USB FAST SERIAL ADAPTER on usbus0
ugen0.11: FTDI at usbus0
... (mangling below is as it appears in dmesg)
da1 at sym0 bus 0 scbus0 target 1 lun 0uftdi14: USB FAST SERIAL ADAPTER
on usbus0
da1: SEAGATE ST336807LW 0C01 Fixed Direct Access SCSI-3 device uftdi15:
USB FAST SERIAL ADAPTER on usbus0
...
Root mount waiting for: usbus0
ugen0.12: vendor 0x0409 at usbus0
uhub3: vendor 0x0409 product 0x0050, class 9/0, rev 2.00/1.00, addr 12
on usbus0
Root mount waiting for: usbus0
uhub3: 7 ports with 7 removable, self powered
ugen0.13: FTDI at usbus0
uftdi16: FT232R USB UART on usbus0
Root mount waiting for: usbus0
ugen0.14: FTDI at usbus0
uftdi17: FT232R USB UART on usbus0
Root mount waiting for: usbus0
ugen0.15: FTDI at usbus0
uftdi18: FT232R USB UART on usbus0
ugen0.16: FTDI at usbus0Root mount waiting for:
usbus0
uftdi19: FT232R USB UART on usbus0
ugen0.17: FTDI at usbus0
uftdi20: FT232R USB UART on usbus0
Root mount waiting for: usbus0
ugen0.18: FTDI at usbus0
uftdi21: FT232R USB UART on usbus0
Root mount waiting for: usbus0
ugen0.19: vendor 0x0409 at usbus0
uhub4: vendor 0x0409 product 0x005a, class 9/0, rev 2.00/1.00, addr 19
on usbus0
uhub4:
