Re: ps -axl during textdumps occasionally segfaults with a HUGE ps.core

On Thu, 30 Jul 2009 09:00:50 +0200
Thomas Backman <serenity_at_exscape.org> wrote:

> On Jul 29, 2009, at 22:19, Thomas Backman wrote:
> 
> > All the info I happen to have:
> >
> > (from core.txt.X)
> > "ps -axl
> >
> > Segmentation fault (core dumped)"
> >
> > The last core I got (/ps.core) was 1076211712 bytes (1026 MiB).
> >
> > Anyone else with this problem?
> > Unfortunately, I deleted the most recent core and so can't gdb it,  
> > at least not right now. I did try it on the first one, but got a  
> > very broken backtrace.
> >
> > Regards,
> > Thomas
> More detail:
> 
> Core was generated by `ps'.
> Program terminated with signal 11, Segmentation fault.
> Reading symbols from /lib/libm.so.5...(no debugging symbols  
> found)...done.
> Loaded symbols for /lib/libm.so.5
> Reading symbols from /lib/libkvm.so.5...(no debugging symbols  
> found)...done.
> Loaded symbols for /lib/libkvm.so.5
> Reading symbols from /lib/libc.so.7...(no debugging symbols  
> found)...done.
> Loaded symbols for /lib/libc.so.7
> Reading symbols from /libexec/ld-elf.so.1...(no debugging symbols  
> found)...done.
> Loaded symbols for /libexec/ld-elf.so.1
> #0  0x00000008009603a6 in bcopy () from /lib/libc.so.7
> (gdb) bt
> #0  0x00000008009603a6 in bcopy () from /lib/libc.so.7
> #1  0x0000000800770141 in _kvm_freeprocs () from /lib/libkvm.so.5
> #2  0x0000000800770870 in kvm_getprocs () from /lib/libkvm.so.5
> #3  0x0000000000405322 in uname ()
> #4  0x0000000000401f0e in ?? ()
> #5  0x0000000800539000 in ?? ()
> #6  0x0000000000000000 in ?? ()
> #7  0x0000000000000006 in ?? ()
> #8  0x00007fffffffef40 in ?? ()
> #9  0x00007fffffffef43 in ?? ()
> #10 0x00007fffffffef46 in ?? ()
> #11 0x00007fffffffef5b in ?? ()
> #12 0x00007fffffffef5e in ?? ()
> #13 0x00007fffffffef72 in ?? ()
> #14 0x0000000000000000 in ?? ()
> ...
> #586 0x0000000000000000 in ?? ()
> #587 0x0073702f6e69622f in ?? ()
> #588 0x247c8d48002454ff in ?? ()
> #589 0x01a1c0c748006a10 in ?? ()
> #590 0x66fdebf4050f0000 in ?? ()
> #591 0x9066669066669066 in ?? ()
> #592 0x00007fffffffeda0 in ?? ()
> #593 0x0000000000000006 in ?? ()
> #594 0x00007fffffffedd8 in ?? ()
> #595 0x0000000000000004 in ?? ()
> Cannot access memory at address 0x800000000000
> (gdb)
> 
> Not exactly a lot of useful info. Still, anyone else noticed this?
> Oh, and this core was *exactly* as big as the previous one
> (1076211712 bytes)...
> 

I'm seeing 'ps -axl' segfault too - it seems operating on core files is
broken, because unsurprisingly I can get it to segfault just by running
'ps -axl -M /var/crash/vmcore.2'.  During boot I only get a partial
core file (350MB) because it fills my root partition, but the full core
is 1GB.

-- 
Bruce Cran