PROBLEM: pppd with mru and mtu set to 2000 has caused a kernel panic

[Ehreth Imre]

[1.] 
pppd with mru and mtu set to 2000 has caused a kernel panic

[2.] 
I was trying l2tpd from www.marko.net. I haved tryed to speed up
the connection. I have tested with to i386 linux (RH 6.2). Both endpoint
have run pppd with mtu and mru specified as 2000 and l2tpd had
tunneled the ppp packets between them. After transfering 1-2MB over
the link with ftp one of the machines has died.

[3.] Keywords: 
networking, ppp, l2tpd

[4.] Kernel version:
Linux version 2.2.16 ([e-mail]) (gcc version
egcs-2.91.66 19990314/Linux (egcs-1.1.2 release)) #11 Wed Jun 28 
09:31:48 CEST 2000

[5.] Oops:
Kernel panic: skput:over: d0845fc7:1863 put:1863 dev:ppp0
In interrupt handler - not syncing

[6.] 
If it is needed I can send a patch or the whole l2tpd with the 
configuration what I have used. (But I think l2tpd is irrelevant here)

[7.] Environment

[7.1] Software 
Kernel modules         2.3.10-pre1
Gnu C                  egcs-2.91.66
Binutils               2.9.5.0.22
Linux C Library        2.1.3
Dynamic linker         ldd (GNU libc) 2.1.3
Procps                 2.0.6
Mount                  2.10f
Net-tools              1.54
Console-tools          0.3.3
Sh-utils               2.0
Modules Loaded         st

[7.2] Processor
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 3
model name      : Pentium II (Klamath)
stepping        : 4
cpu MHz         : 267.278
cache size      : 512 KB
fdiv_bug        : no
hlt_bug         : no
sep_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov mmx
bogomips        : 532.48

[7.3] Modules
ppp                    20140   0 (autoclean)
slhc                    4440   0 (autoclean) [ppp]
st                     25160   0 (unused)

[7.4] SCSI
Attached devices: 
Host: scsi0 Channel: 00 Id: 00 Lun: 00
  Vendor: SEAGATE  Model: ST39140W         Rev: 1444
  Type:   Direct-Access                    ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 01 Lun: 00
  Vendor: SEAGATE  Model: ST39140W         Rev: 1206
  Type:   Direct-Access                    ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 03 Lun: 00
  Vendor: HP       Model: C1533A           Rev: A708
  Type:   Sequential-Access                ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 05 Lun: 00
  Vendor: SONY     Model: CD-ROM CDU625-S  Rev: 1.0r
  Type:   CD-ROM                           ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 06 Lun: 00
  Vendor: YAMAHA   Model: CRW6416S         Rev: 1.0c
  Type:   CD-ROM                           ANSI SCSI revision: 02

[7.5] 
pppd version 2.3.11 (from ppp-2.3.11-4.i368.rpm at both endpoint).

Imre Ehreth
e-mail: [e-mail]