Interrupt spawns Zombies and Vampires

[Peter Renzland]

Denys, thanks for thinking about my problem report.   I'm not a  
developer, just a sys admin.  Unfortunately I don't have a cross- 
compiler and related tools.  I came to this Busybox forum because I  
thought that I would get competent answers (I am :-), and in the hope  
that this might be a known problem (it isn't).

I will happily forward the config information, etc., to the Tomato  
developer(s). ... more in line ...

On 09  Jan 13, at 21:31 , Denys Vlasenko wrote:

> On Tuesday 13 January 2009 03:37, Peter Renzland wrote:
>> OK.  Attaching the config_g
>
> I see CONFIG_CROSS_COMPILER_PREFIX="mipsel-uclibc-"
>
> Can you build native i386 or x86_64 busybox with the same .config
> (just set CONFIG_CROSS_COMPILER_PREFIX="")?
> Does it still exhibit this?

I cannot do so myself.
BTW, I have a tiny Aztech DSL695EU modem/router with a very old  
Busybox, which works fine.  It even has job control:
BusyBox v0.61.pre (2008.10.10-08:51+0000) Built-in shell (ash)

> Which libc do you use on your embedded device?

Not sure.  I see references to mipsel-uclibc in the Makefile.

I also see this, in ash.c:

#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 1
typedef enum __rlimit_resource rlim_t;
#endif

BTW, for anyone interested:

http://www.polarcloud.com/f/Tomato_1_23.7z

>> Shell is ash:
>>
>> BusyBox v1.12.2 (2008-12-05 06:20:11 PST) built-in shell (ash)
>> also
>> BusyBox v1.12.3 (2008-12-14 02:54:58 PST) built-in shell (ash)
>
>
> # ### it says ash
> # ps
> PID USER       VSZ STAT COMMAND
> ...
> 21313 root      1984 S    -sh
> 21315 root      1960 R    ps
> # ### but ps says sh
>
> So what? your /bin/sh is a symlink to ash, thus /bin/sh is ash.
> I see no problem here.

I understand, but you did ask and I didn't want to keep the  
information from you.  After all, commands can and do act differently,  
depending on the name by which they are invoked.

>> # ping ac.ca
> PING ac.ca (69.90.47.27): 56 data bytes
> 64 bytes from 69.90.47.27: seq=0 ttl=43 time=132.217 ms
> 64 bytes from 69.90.47.27: seq=1 ttl=43 time=132.336 ms
> #
> --- ac.ca ping statistics ---
> 2 packets transmitted, 2 packets received, 0% packet loss
> round-trip min/avg/max = 132.217/132.276/132.336 ms
>
> # ### SIGINT ^C
> # ps
> # ### vampire shell eats my command ...
> # ps
> PID USER       VSZ STAT COMMAND
>   1 root      1720 S    init noinitrd
>   2 root         0 SW   [keventd]
>
>
>
> Mine doesn't:
>
> # ping ac.ca
> PING ac.ca (69.90.47.27): 56 data bytes
> 64 bytes from 69.90.47.27: seq=0 ttl=47 time=181.496 ms
> 64 bytes from 69.90.47.27: seq=1 ttl=47 time=180.338 ms
> ^C
> --- ac.ca ping statistics ---
> 3 packets transmitted, 2 packets received, 33% packet loss
> round-trip min/avg/max = 180.338/180.917/181.496 ms

Please understand that I am reporting and providing evidence for what  
clearly is a problem.  You and I both know perfectly well that *this*  
particular Busybox implementation is defective.  So, of course, any  
correct implementation won't have these problems.  I'm hoping to learn  
what causes them, so that I might send that information to the  
developer and ask him to fix it. :-)


> # ps
> PID   USER     TIME   COMMAND
>   1 root       0:00 /bin/sh /init
>   2 root       0:00 [kthreadd]
>   3 root       0:00 [migration/0]
>
>
>
> Having said that, these is a few differences in your and my setup:
>
> * I use native build against glibc
> * I use svn, which have a few fixes in ash.
>
> I will mail you latest terball separately. Please try it and let me  
> know.
> --
> vda

Thanks!