On Tue, 2007-08-07 at 10:27 +0200, John Sigler wrote:
> Daniel Walker wrote:
>
> > John Sigler wrote:
> >
> >> Would anyone care to comment?
> >
> > I'm not sure if this is the answer that you're looking for, but yes you
> > certainly will find fixed bug is older version of the tree.
>
> I am not a kernel hacker, therefore I can only imagine how complex it is
> to bring real-time to Linux. For some reason, I had come to believe that
> the case of a single CPU without dynticks had been "solved" in the more
> recent kernels (say 2.6.20), and that development had moved on, and was
> now active in more "complex" areas like SMP/multi-core, dynticks, etc.
There is always a chance of something not working, or a regression
getting introduced in any of the code .. -rt is all still a development
tree too, so it may not always be stable.
> >> Perhaps I could also test a different strategy, such as xenomai?
> >> http://www.xenomai.org/
> >
> > If it's a kernel bug it's not going to matter if you use a xenomai skin
> > or not.. If you use some other real time layer that might fix it ..
>
> *If* it is a bug in the -rt patch, then Adeos/Xenomai coupled with a
> vanilla Linux kernel should not be affected by the same bug. Unless my
> logic is broken somewhere.
I wouldn't think so, but then what if Adeos/Xenomai has a new bug?
> > you really need to test your app on a current version of the kernel ..
> > We as developers generally don't support out dated trees..
>
> This is the part I don't understand. I work for a tiny company with
> limited resources. It's infeasible for me to track every new kernel
> release and upgrade every time. I need to pick a kernel version that has
> the functionality we need, test it thoroughly with my app, and then
> never touch that kernel again.
Ok ..
> Unless I am mistaken, some people (like Thomas) have been deploying
> systems based on PREEMPT_RT (or just -hrt) in indutrial settings for a
> long time. (As far back as 2.6.15?) Obviously many bugs have been fixed
> since then, which means that these versions contained many bugs.
It's not a stretch to imagine. These real time chance has already been
included in commercial distros, and are generally getting made into
various products right now .. Just like what your doing .
> How does one react when an important bug in found in a system that is
> already in the field? Do they provide a way to upgrade the kernel (like
> consumer-grade network routers)? Do they replace the complete system?
I don't really know the details of this , but I would imagine there is
some sort of upgrade path for say routers .. I've heard people talk
about cell phone upgrading their software over the air.. It would be a
difficult proposition to say make some specific kernel static forever ..
Even the mainline stable kernel has bugs that get fixed..
Daniel
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
