Re: making kmalloc BUG() might not be a good idea

["David S. Miller" <davem@davemloft.net>]

From: Nick Piggin <nickpiggin@yahoo.com.au>
Date: Fri, 23 Sep 2005 17:58:00 +1000

> Then you'll get people not enabling it on real workloads, or
> tuning it off if it bugs them. No, the point of having a WARN
> there is really for people like SGI to detect a few rare failure
> cases when they first boot up their 1024+ CPU systems. It is not
> going to spam anyone's logs (and if it does it *needs* fixing).

SGI (and people "like" them) can't enable a debug option when bringing
up new changes for the first time on that huge system?  Why is this?

What in the world are all these CONFIG_*DEBUG* options for then?
They are there for "I'm doing something radically new, or my new
change isn't working, therefore I need more debugging than usual."

We want it to spam the logs, sure, during _development_.  We don't
want it on production systems where any kind of downtime is a very
serious problem.  Rate limited, maybe, but not for every call as
that's simply asking for trouble.

This is why we have things like net_ratelimit() in the networking btw.
It's there so you can't remotely spam someone's logs just becuase you
figured out the "bug of the week" magic packet that erroneously
generates a huge number of log messages.

If we know how to make certain classes of bugs non-lethal, we should
do so because there will always be bugs. :-)  This change makes
previously non-lethal bugs potentially kill the machine.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/