[BusyBox 0005004]: Shell command will hang minicom. When minicom is hanging, reboot/poweroff commands are useless

[bugs at busybox.net]

A NOTE has been added to this issue. 
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http://busybox.net/bugs/view.php?id=5004 
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Reported By:                xmuchgw
Assigned To:                BusyBox
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Project:                    BusyBox
Issue ID:                   5004
Category:                   Other
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     assigned
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Date Submitted:             09-15-2008 22:08 PDT
Last Modified:              09-16-2008 14:38 PDT
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Summary:                    Shell command will hang minicom. When minicom is
hanging, reboot/poweroff commands are useless
Description: 
package:busybox
version:1.10.2

When I execute following shell script on my development board in
HyperTerminal,
about 5~30 minuters later, the HyperTerminal hangs until press any key
from keyboard.

   while true
   do
        ls -l
   done

When my HyperTerminal is hanging, I login my development board by telnet.
And found that, reboot and power commands are NOT workable.
But others shell commands, such as cd/ls/ps are workable.
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---------------------------------------------------------------------- 
 Vladimir - 09-15-08 22:35  
---------------------------------------------------------------------- 
Looks like system resources hunger.
Try

   while true
   do
        ls -l
        free
   done

Is free memory decreasing? 

---------------------------------------------------------------------- 
 vda - 09-16-08 14:34  
---------------------------------------------------------------------- 
Regarding your "killall init" strace. It definitely working correctly - it
signaled init with TERM:

# /strace -fF killall init
execve("/usr/bin/killall", ["killall", "init"], [/* 12 vars */]) = 0
...
close(3)                                = 0
kill(1, SIGTERM)                        = 0
exit_group(0)                           = ?

so the reason why init does not reboot, is somewhere in init code (or in
the script run from init when it gets TERM). 

---------------------------------------------------------------------- 
 vda - 09-16-08 14:38  
---------------------------------------------------------------------- 
While you run this:

while true; do ls -l; done

can you determine which telnetd process is responsible for this session,
and run "strace -tt -o telnetd.log -p <telnetd's_pid>" until this hang
happens? Attach resulting log to this bug. (You may want to daemonize
strace process so that it does not require a separate telnet connection to
be open). 

Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
09-15-08 22:08  xmuchgw        New Issue                                    
09-15-08 22:08  xmuchgw        Status                   new => assigned     
09-15-08 22:08  xmuchgw        Assigned To               => BusyBox         
09-15-08 22:35  Vladimir       Note Added: 0011484                          
09-16-08 01:42  xmuchgw        File Added: 2008-09-16.txt                    
09-16-08 14:34  vda            Note Added: 0011494                          
09-16-08 14:38  vda            Note Added: 0011504                          
======================================================================