Re: segfault on kernel v2.4.0

[Dejan Muhamedagic <dejan@xsoft.at>]

I'll try to clarify:

1.  It is a segfault (in losetup).  No oopses.

2.  The kernel (2.4.0) seems to be OK.  loop devices work fine.
Other stuff as well, i.e. sound, pcmcia network.  Furthermore, I
tested the IDEA cipher and it seems to be OK.  So, it is only the
Blowfish code being troubled.

3.  With or without other modules, or in single-user mode, the
same thing happens.  I agree that the log is weird, but I'm no
kernel expert either (what on earth has a cipher module to do with
the pcmcia?).  Also, when I try the same by removing all other
modules previously, in syslog there is a referrence to the
ipchains module :)

4.  All ciphers are compiled as modules.

So, I can switch to IDEA.  Is it advisable to use this cipher in a
production?  Any reports about its stability?  About the
international patch?  Or should I stay put with the v2.2.x kernels
for the time being?

Thanks.

Dejan

On Tue, Jan 30, 2001 at 10:36:26AM -0500, Chris Kuklewicz wrote:
> I have no kernel debugging experience.  There is documentation.  See
> /usr/src/linux/REPORTING-BUGS and
> /usr/src/linux/Documentation/oops-tracing.txt, the latter is really
> helpful here.
>
> On Tue, Jan 30, 2001 at 10:03:33AM +0100, Dejan Muhamedagic wrote:
> > Hello,
> > 
> > Trying to migrate to the new kernel v2.4.0, but I'm failing
> > to get ciphers to work.  The cipher segfaults :(  It doesn't
> 
> I think segfualt is the wrong jargon here.
>
> > matter trying to use the file encrypted with ciphers from
> > v2.2.17 or creating a new one.
> > 
> > I hope you will find the information attached at the bottom
> > of the message useful.
> > 
> 
> Try compiling as loadable modules, instead of compiling it into
> the kernel.  Did you try a 2.4.0 kernel with the *same* config
> options but without the crypto patch?  You should.
> 
> > # insmod -V
> > insmod version 2.4.1
> > # gcc --version
> > 2.95.2
> > # ldd --version
> > ldd (GNU libc) 2.2
> > 
> > from syslog:
> > 
> > Jan 29 00:39:24 hobbes kernel: loop: enabling 8 loop devices
> > Jan 29 00:39:51 hobbes kernel: divide error: 0000
> > Jan 29 00:39:51 hobbes kernel: CPU:    0
> > Jan 29 00:39:51 hobbes kernel: EIP:    0010:[cs46xx:InitArray+314522/152496206]
>                                                ^^^^^^
> That is a sound driver
> 
> > Jan 29 03:28:01 hobbes kernel: cryptoapi: Registered blowfish-cbc (65536)
> > Jan 29 03:28:01 hobbes kernel: divide error: 0000
> > Jan 29 03:28:01 hobbes kernel: CPU:    0
> > Jan 29 03:28:01 hobbes kernel: EIP:    0010:[ds:__insmod_ds_O/lib/modules/2.4.0/kernel/drivers/pcmcia/ds.o_+-304718/96]
> 
> That is a PCMCIA driver, (which I do not have)
> 
> So if it is a bug in the crypto patch, it is a bug that stomps on
> other parts of the kernel, causing the ooops to show up in your sound
> driver and PCMCIA driver.
> 
> Or...it is a problem in your sound driver and PCMCIA driver.
> 
> Again,
> 
> Try to build a clean 2.4.0 or 2.4.1 kernel with the same options, but
> without crypto.
> 
> When you add a crypto patch, try using modules.
> 
> -- 
> Chris
> 
> Linux-crypto:  cryptography in and on the Linux system
> Archive:       http://mail.nl.linux.org/linux-crypto/

-- 
Dejan Muhamedagic                      mailto:dejan@xsoft.at
Xsoft GmbH                               http://www.xsoft.at
Modecenterstr. 14, 1030 Vienna, Austria    +43 1 7963636 676

Linux-crypto:  cryptography in and on the Linux system
Archive:       http://mail.nl.linux.org/linux-crypto/