runaway shell (tcsh) processes and load average

[John Nitis <john@interscape.com>]

Hello,

I'm running OpenBSD binkley 2.4 GENERIC#20 sparc.  Whenever someone
doesn't properly logout of their shell (such as when they are disconnected
due to network troubles) their shell process ends up eating up all
available CPU as a runaway process.  As far as I know this happens across
rlogin, telnet, and secure shell logins.  The shell being used is tcsh.

Recently I grabbed some debugging information on one of the runaway shells
via ktrace and I've included a bit of the kdump output below.

The other question I had relates to the load average.  It's constantly
between 0.10 - 0.20 even when there's nothing running to bring the load
average up that high.  Is there anything that may be causing this on
OpenBSD/sparc? (110mhz sparc4 with 64mb ram) `top' shows:

CPU states:  0.5% user,  0.0% nice,  1.0% system,  0.0% interrupt, 98.5%
idle
Memory: Real: 1736K/26M act/tot  Free: 35M  Swap: 1496K/119M used/tot
  
  PID USERNAME PRI NICE  SIZE   RES STATE WAIT     TIME    CPU COMMAND
24547 root       2    0  324K  148K idle  select  10:05  0.00% sshd1
10726 root       2    0  640K  176K sleep select   2:23  0.00% httpd
...

I'd appreciate it if someone could cc: my email address
<john@interscape.com> if a solution is available, as I'm not a member of
this mailing list.  Thanks in advance for any assistance.


ktrace from runaway tcsh process:

 29237 tcsh     CALL  write(0x11,0x5ed18,0x9)
 29237 tcsh     RET   write -1 errno 5 Input/output error
 29237 tcsh     CALL  issetugid
 29237 tcsh     RET   issetugid 0
 29237 tcsh     CALL  open(0xf7ffec10,0,0)
 29237 tcsh     NAMI  "/usr/share/nls/C/libc.cat"
 29237 tcsh     RET   open 0
 29237 tcsh     CALL  fstat(0,0xf7ffeb48)
 29237 tcsh     RET   fstat 0
 29237 tcsh     CALL  mmap(0,0xe5a,0x1,0x1,0,0,0,0)
 29237 tcsh     RET   mmap 135708672/0x816c000
 29237 tcsh     CALL  close(0)
 29237 tcsh     RET   close 0
 29237 tcsh     CALL  munmap(0x816c000,0xe5a)
 29237 tcsh     RET   munmap 0
 29237 tcsh     CALL  lseek(0x10,0,0,0,0x2,0)
 29237 tcsh     RET   lseek -1 errno 9 Bad file descriptor
 29237 tcsh     CALL  ioctl(0xf,TIOCSPGRP,0xf7ffefa4)
 29237 tcsh     RET   ioctl -1 errno 25 Inappropriate ioctl for device
 29237 tcsh     CALL  sigreturn(0x5cf18)
 29237 tcsh     RET   sigreturn JUSTRETURN
 29237 tcsh     CALL  sigprocmask(0x1,0)
 29237 tcsh     RET   sigprocmask 2
 29237 tcsh     CALL  sigprocmask(0x3,0)
 29237 tcsh     RET   sigprocmask 2
 29237 tcsh     CALL  close(0)
 29237 tcsh     RET   close -1 errno 9 Bad file descriptor
 29237 tcsh     CALL  close(0x1)
 29237 tcsh     RET   close -1 errno 9 Bad file descriptor
 29237 tcsh     CALL  close(0x2)
 29237 tcsh     RET   close -1 errno 9 Bad file descriptor

..and so on in numerical order until close(0x3f).  After the failed
close(0x3f), it restarts from the beginning.