http://bugzilla.kernel.org/show_bug.cgi?id=6197

http://bugzilla.kernel.org/show_bug.cgi?id=6197

[Andrew Morton]

The reporter claims this is a netfilter bug.

Re: http://bugzilla.kernel.org/show_bug.cgi?id=6197

[Patrick McHardy]

Andrew Morton wrote:
> The reporter claims this is a netfilter bug.
> 

ipt_IMQ                 1949  36
imq                     4023  0

He patched his kernel with the IMQ device, which is known to cause all
kinds of weird problems.

Re: http://bugzilla.kernel.org/show_bug.cgi?id=6197

[Michael Tokarev]

Patrick McHardy wrote:
[]
> He patched his kernel with the IMQ device, which is known to cause all
> kinds of weird problems.

Wich problems?  Known to whom?

I was considering using imq for our needs (not done yet), and from the
FAQ at http://www.linuximq.net/faq.html (item #3, "Is it stable?") it
seems there's no problems except of gre tunnels and locally generated
traffic...

Googling for "imq linux problem" shows usual pile of various user
support questions (how to configure.. what did I do wrong.. etc),
but nothing relevant.

So... I'm curious whenever the claim on linuximq.net site about the
stability is true, or there in fact are some real issue...

Thanks.

/mjt

Re: http://bugzilla.kernel.org/show_bug.cgi?id=6197

[Patrick McHardy]

Michael Tokarev wrote:
> Patrick McHardy wrote:
> []
> 
>>He patched his kernel with the IMQ device, which is known to cause all
>>kinds of weird problems.
> 
> 
> Wich problems?  Known to whom?

Known to me (who wrote the original implementation of the current IMQ
device) and numerous people who were hit by them. IIRC it does some
invalid skb refcounting hacks which result in crashes in certain
scenarios - but I don't remeber the exact details.

> I was considering using imq for our needs (not done yet), and from the
> FAQ at http://www.linuximq.net/faq.html (item #3, "Is it stable?") it
> seems there's no problems except of gre tunnels and locally generated
> traffic...
> 
> Googling for "imq linux problem" shows usual pile of various user
> support questions (how to configure.. what did I do wrong.. etc),
> but nothing relevant.

The lartc list had lots of reports of crashes. I guess "imq crash" or
"imq oops" will give better results.

> So... I'm curious whenever the claim on linuximq.net site about the
> stability is true, or there in fact are some real issue...

>From what I know these problems haven't been fixed. Current kernels
include Jamal's tc actions and the ifb-Device, which obsolete IMQ
anyway.