Kernel bug? when using lucent modem
I have lucent modem and martian module for it. I had no trouble
with it if there were not this one incident. When I dialed up
after making connection pppd (modem connection) freezed. And
there was noise present on phone line (when I picked up handset)
even after I killed pppd. Computer released
phone line only when I restarted OS shortly after.
Since then modem again works fine.
I am just curious what could be reason for this behavior.
Misko
Here are some more info:
$ lspci -n
00:13.0 0780: 11c1:0440 (rev 01)
$ lspci -v
00:13.0 Communication controller: Agere Systems 56k WinModem (rev 01)
Subsystem: Agere Systems LT WinModem 56k Data+Fax+Voice+Dsvd
Flags: bus master, medium devsel, latency 0, IRQ 11
Memory at fedffc00 (32-bit, non-prefetchable) [size=256]
I/O ports at e400 [size=8]
I/O ports at e800 [size=256]
Capabilities: [f8] Power Management version 2
Here is part of /var/log/syslog:
Mar 18 13:16:35 alfa pppd[3526]: Serial connection established.
Mar 18 13:16:35 alfa pppd[3526]: using channel 2
Mar 18 13:16:35 alfa pppd[3526]: Using interface ppp0
Mar 18 13:16:35 alfa pppd[3526]: Connect: ppp0 <--> /dev/modem
Mar 18 13:16:36 alfa pppd[3526]: sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x6e09f4ae> <pcomp> <accomp>]
Mar 18 13:16:37 alfa kernel: skb_under_panic: text:ccac3d97 len:11 put:1 head:c2b28800 data:c2b287ff tail:c2b2880a end:c2b28e00 dev:<NULL>
Mar 18 13:16:37 alfa kernel: ------------[ cut here ]------------
Mar 18 13:16:37 alfa kernel: kernel BUG at net/core/skbuff.c:111!
Mar 18 13:16:37 alfa kernel: invalid opcode: 0000 [#1]
Mar 18 13:16:37 alfa kernel: SMP
Mar 18 13:16:37 alfa kernel: Modules linked in: ppp_deflate zlib_deflate bsd_comp ppp_async crc_ccitt isofs ppp_generic slhc ipt_LOG xt_state ipt_MASQUERADE iptable_nat ip_nat ip_conntrack nfnetlink iptable_filter ip_tables x_tables tun button ac battery ipv6 nls_iso8859_1 nls_cp850 vfat fat dm_snapshot dm_mirror dm_mod kqemu loop tsdev snd_ens1371 gameport snd_seq_dummy snd_seq_oss snd_seq_midi snd_seq_midi_event snd_seq snd_rawmidi snd_seq_device snd_ac97_codec snd_ac97_bus floppy snd_pcm_oss snd_mixer_oss serio_raw parport_pc parport rtc snd_pcm snd_timer psmouse i2c_piix4 intel_agp agpgart i2c_core pcspkr snd soundcore snd_page_alloc martian_dev shpchp pci_hotplug evdev ext3 jbd mbcache ide_cd cdrom ide_disk uhci_hcd usbcore piix generic ide_core thermal processor fan
Mar 18 13:16:37 alfa kernel: CPU: 0
Mar 18 13:16:37 alfa kernel: EIP: 0060:[<c02247dc>] Tainted: PF VLI
Mar 18 13:16:37 alfa kernel: EFLAGS: 00013086 (2.6.18-4-686 #1)
Mar 18 13:16:37 alfa kernel: EIP is at skb_under_panic+0x37/0x45
Mar 18 13:16:37 alfa kernel: eax: 00000071 ebx: c02a16b6 ecx: 00003082 edx: 00003000
Mar 18 13:16:37 alfa kernel: esi: 00000000 edi: c2b2880c ebp: c2b2880b esp: c75e1eb0
Mar 18 13:16:37 alfa kernel: ds: 007b es: 007b ss: 0068
Mar 18 13:16:37 alfa kernel: Process martian_modem (pid: 2397, ti=c75e0000 task=cbf13aa0 task.ti=c75e0000)
Mar 18 13:16:37 alfa kernel: Stack: c02aec03 ccac3d97 0000000b 00000001 c2b28800 c2b287ff c2b2880a c2b28e00
Mar 18 13:16:37 alfa kernel: c02a16b6 cb9c0520 000000ff ccac3d9c 00000000 c8173410 c26ed800 cb92ce00
Mar 18 13:16:37 alfa kernel: 00003286 00000001 00000046 c26ed800 c8173400 00000046 c01ff6aa 00000036
Mar 18 13:16:37 alfa kernel: Call Trace:
Mar 18 13:16:37 alfa kernel: [<ccac3d97>] ppp_asynctty_receive+0x380/0x555 [ppp_async]
Mar 18 13:16:37 alfa kernel: [<ccac3d9c>] ppp_asynctty_receive+0x385/0x555 [ppp_async]
Mar 18 13:16:37 alfa kernel: [<c01ff6aa>] pty_write+0x2a/0x34
Mar 18 13:16:37 alfa kernel: [<c01fda66>] write_chan+0x21d/0x294
Mar 18 13:16:37 alfa kernel: [<c0117778>] default_wake_function+0x0/0xc
Mar 18 13:16:37 alfa kernel: [<c01fb570>] tty_write+0x147/0x1d8
Mar 18 13:16:37 alfa kernel: [<c01fd849>] write_chan+0x0/0x294
Mar 18 13:16:37 alfa kernel: [<c01fb429>] tty_write+0x0/0x1d8
Mar 18 13:16:37 alfa kernel: [<c015a5db>] vfs_write+0xa1/0x143
Mar 18 13:16:37 alfa kernel: [<c015abcb>] sys_write+0x3c/0x63
Mar 18 13:16:37 alfa kernel: [<c0102c11>] sysenter_past_esp+0x56/0x79
Mar 18 13:16:37 alfa kernel: Code: 0f 45 de 53 ff b0 a8 00 00 00 ff b0 a4 00 00 00 ff b0 a0 00 00 00 ff b0 9c 00 00 00 52 ff 70 60 51 68 03 ec 2a c0 e8 8e 91 ef ff <0f> 0b 6f 00 9c eb 2a c0 83 c4 24 5b 5e c3 56 53 bb b6 16 2a c0
Mar 18 13:16:37 alfa kernel: EIP: [<c02247dc>] skb_under_panic+0x37/0x45 SS:ESP 0068:c75e1eb0
Mar 18 13:16:39 alfa pppd[3526]: sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x6e09f4ae> <pcomp> <accomp>]
Mar 18 13:17:00 alfa last message repeated 7 times
Mar 18 13:17:01 alfa /USR/SBIN/CRON[3564]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Mar 18 13:17:03 alfa pppd[3526]: sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x6e09f4ae> <pcomp> <accomp>]
Mar 18 13:17:04 alfa pppd[3526]: Terminating on signal 15
Reply to: