panic w/ USB<->serial adapter and modem

[Marcin Wisnicki]

On Sat, 18 Dec 2004 18:52:01 -0800, Steve Watt <steve at watt.com> wrote:
> I've got a 5.3-STABLE (updated 19 Nov around 2000PST) machine that
> has serious difficulty when I attempt to use the modems that are
> attached via the Prolofic Technology PL2303 serial adapters.

I'm having similar problems on that device with an isdn modem (it
works like normal serial modem) and ppp, using latest 5-stable.
Sometimes under heavy load (for example during buildworld),
system will panic with "uhci_abort_xfer: not in process context".

Since I've finally managed to get a crashdump, I'm able to post a backtrace:

make gdbinit
kgdb -n0 kernel.debug
(kgdb) getsyms
(kgdb) bt
#0  doadump () at pcpu.h:159
#1  0xc0491773 in boot (howto=0x104) at /usr/src/sys/kern/kern_shutdown.c:410
#2  0xc0491acb in panic (fmt=0xc0752f24 "uhci_abort_xfer: not in
process context")
    at /usr/src/sys/kern/kern_shutdown.c:566
#3  0xc073feea in uhci_abort_xfer (xfer=0xc1763e00,
status=USBD_NORMAL_COMPLETION)
    at /usr/src/sys/modules/usb/../../dev/usb/uhci.c:1956
#4  0xc073f6b9 in uhci_timeout_task (addr=0x0) at
/usr/src/sys/modules/usb/../../dev/usb/uhci.c:1534
#5  0xc0738f2e in usb_task_thread (arg=0x0) at
/usr/src/sys/modules/usb/../../dev/usb/usb.c:464
#6  0xc04779af in fork_exit (callout=0xc0738e90 <usb_task_thread>,
arg=0x0, frame=0x0)
    at /usr/src/sys/kern/kern_fork.c:807
#7  0xc05d41ac in fork_trampoline () at /usr/src/sys/i386/i386/exception.s:209

This looks like the one in kern/67301, though I don't know why some
arguments in my backtrace are wrong (I suppose they shouldn't be 0).
I compiled almost everything in modules, but I hope that I've loaded
symbols correctly

usbdevs -v
Controller /dev/usb0:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000),
VIA(0x0000), rev 1.00
 port 1 addr 2: full speed, self powered, config 1, DeskJet
920C(0x1504), Hewlett-Packard(0x03f0), rev 1.00
 port 2 addr 3: full speed, power 100 mA, config 1, PL2303 Serial
adapter (ATEN/IOGEAR UC232A)(0x2303), Prolific Technology(0x067b), rev
2.02
Controller /dev/usb1:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000),
VIA(0x0000), rev 1.00
 port 1 powered
 port 2 powered
Controller /dev/usb2:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000),
VIA(0x0000), rev 1.00
 port 1 powered
 port 2 powered
Controller /dev/usb3:
addr 1: high speed, self powered, config 1, EHCI root hub(0x0000),
VIA(0x0000), rev 1.00
 port 1 powered
 port 2 powered
 port 3 powered
 port 4 powered
 port 5 powered
 port 6 powered