ISDN audio oops and failure to receive data (2.1.127-pre2)

David Woodhouse (David.Woodhouse@mvhi.com)
Sat, 07 Nov 1998 01:01:46 +0000


I was trying to get ISDN audio to work on my Teles 16.3 PnP, using minicom
after vbox failed to receive incoming messages, leaving only empty files.

When I make a voice call, and tell it 'AT+VRX' to start receiving audio
data, it doesn't give me any data.

If I use 'AT+VTX' to transmit audio data, I can hear clicks when I type on the
keyboard. So I exited minicom, and tried 'cp lumberjack.au /dev/ttyI0'. At
which point it fell over.

Could this be another symptom of the same problem with packet queue handling
which is sometimes causing outgoing packets to be queued forever?
(cf. http://www.linuxhq.com/lnxlists/linux-kernel/lk_9809_02/msg00075.html )

Warning: kfree_skb passed an skb still on a list (from c19e1340).
Unable to handle kernel NULL pointer dereference at virtual address 00000004
current->tss.cr3 = 0010100, %cr3 = 0010100
*pde = 00000000
Oops: 0002
CPU: 0
EIP: 0010:[<c01bc5c6>]
EFLAGS: 00010046
eax: c19e1340 ebx: 00000246 ecx: c0081148 edx: 00000000
esi: 00000000 edi: c00810bc ebp: c0219f48 esp: c0219f04
ds: 0018 es: 0018 ss: 018
Process swapper (pid:0, process nr: 0, stackpage=c0219000)
Stack: 00000001 c01c0ecc c00810bc c00810bc 00000028 c01b46e8 00000004 c01b4714
00000000 c0111899 00000000 00000001 c023a944 00000000 00000004 00000000
00000296 c0219f60 c0117b7d 00000000 02c1372f c0218000 c010a978 00001ff0
Call Trace: [<c01c0ecc>] [<c01b46e8>] [<c01b4714>] [<c0111899>] [<c0117b7d>] [<c010a978>] [<c01098d8>]
[<c0108055>] [<c010983c>] [<c0106084>] [<c0106073>] [<c0106000>] [<c0100176>]
Code: 89 4a 04 89 97 8c 00 00 00 c7 00 00 00 00 00 c7 40 04 00 00
Aiee, killing interrupt handler
Kernel panic: Attempted to kill the idle task!
In swapper task - not syncing
Using `./System.map' to map addresses to symbols.

>>EIP: c01bc5c6 <isdn_tty_tint+26/10c>
Trace: c01c0ecc <isdn_tty_modem_xmit+3c/54>
Trace: c01b46e8 <isdn_timer_funct>
Trace: c01b4714 <isdn_timer_funct+2c/100>
Trace: c0111899 <timer_bh+305/34c>
Trace: c0117b7d <do_bottom_half+49/64>
Trace: c010a978 <do_IRQ+38/3c>
Trace: c01098d8 <ret_from_intr>
Trace: c0108055 <sys_idle+65/c8>
Trace: c010983c <system_call+34/38>
Trace: c0106084 <init>
Trace: c0106073 <cpu_idle+7/18>
Trace: c0106000 <get_options>
Trace: c0100176 <L6>
Code: c01bc5c6 <isdn_tty_tint+26/10c>
Code: c01bc5c6 <isdn_tty_tint+26/10c> 89 4a 04 movl %ecx,0x4(%edx)
Code: c01bc5c9 <isdn_tty_tint+29/10c> 89 97 8c 00 00 movl %edx,0x8c(%edi)
Code: c01bc5cf <isdn_tty_tint+2f/10c> c7 00 00 00 00 movl $0x0,(%eax)
Code: c01bc5d5 <isdn_tty_tint+35/10c> c7 40 04 00 00 movl $0x90000000,0x4(%eax)
Code: c01bc5dc <isdn_tty_tint+3c/10c> 90 nop
Code: c01bc5dd <isdn_tty_tint+3d/10c> 90 nop

0xc01bc5c6 is in isdn_tty_tint (/usr/src/linux/include/linux/skbuff.h:329).
324 result = NULL;
325 if (next != prev) {
326 result = next;
327 next = next->next;
328 list->qlen--;
329 next->prev = prev;
330 prev->next = next;
331 result->next = NULL;
332 result->prev = NULL;
333 result->list = NULL;

---- ---- ----
David Woodhouse David.Woodhouse@mvhi.com Office: (+44) 1223 810302
Project Leader, Process Information Systems Mobile: (+44) 976 658355
Axiom (Cambridge) Ltd., Swaffham Bulbeck, Cambridge, CB5 0NA, UK.
finger dwmw2@ferret.lmh.ox.ac.uk for PGP key.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/