[grsec] exec_logging bug?

[Kamil Kaczkowski]

Hello.
I've experienced very strange behaviour on Linux 2.4.31(Debian Woody, x86)
with grsecurity today.
Doing:
echo 1 > /proc/sys/kernel/grsecurity/exec_logging
caused severe performance penalty - system started running really slow,
with top showing system cpu load > 100 %(up to 300 %) and negative cpu
idle time.
After turning it off everything returned to normal state.
The strangest thing is that the system was running this kernel for over a
month without any change and I was using exec_logging without any
problems. Overall I've been using this feature for years on many
servers and something like this never happened before.
The problem is now reproducible every time, I didn't try rebooting the
system yet.
What information could I provide to track this down?
This is production server, so I'm limited in my options, but I'll do my
best to debug this.
Regards.
--
Kamil Kaczkowski
kamil at kamil.eisp.pl