id	summary	reporter	owner	description	type	status	component	version	resolution	keywords	cc	guest	host
7273	VirtualBox floods my errors.log => Fixed in SVN	Prikrutil		"=== Description ===

Every time my system loads vboxdrv, the following message is written to errors.log:

{{{
Jul 22 18:32:02 myhost kernel: vboxdrv: Warning: 2.6.31+ kernel detected. Most likely the hardware performance
Jul 22 18:32:02 myhost kernel: vboxdrv: counter framework which can generate NMIs is active. You have to prevent
Jul 22 18:32:02 myhost kernel: vboxdrv: the usage of hardware performance counters by
Jul 22 18:32:02 myhost kernel: vboxdrv:   echo 2 > /proc/sys/kernel/perf_counter_paranoid
}}}

My errors.log is full of these messages and I can't do anything with this, because there is no ""/proc/sys/kernel/perf_counter_paranoid"" file in my system. It's very annoying.

Also I'm not sure that doing ""echo 2 > /proc/sys/kernel/perf_counter_paranoid"" before loading vboxdrv would make these errors go away. According to [http://www.virtualbox.org/browser/trunk/src/VBox/HostDrivers/Support/linux/SUPDrv-linux.c#L500 SUPDrv-linux.c], no matter what /proc/sys/kernel/perf_counter_paranoid file contains, the error will always be logged.

=== How to fix that ===

I know that real fix is quite difficult to implement right, [http://forums.virtualbox.org/viewtopic.php?f=7&t=33391#p149488 so we won't see it in 3.2.8]

But there are two small fixes which are easy to implement in 3.2.8 and will make those messages much less annoying:

'''1.''' Change /proc/sys/kernel/perf_'''counter'''_paranoid to /proc/sys/kernel/perf_'''event'''_paranoid in the warning message

'''2.''' If /proc/sys/kernel/perf_event_paranoid already contains 2, there shouldn't be any warnings in errors.log. [http://vbox.innotek.de/pipermail/vbox-dev/2010-June/002860.html This has been disscused] in mailing list

=== Additional info ===

Discussion in the forum: http://forums.virtualbox.org/viewtopic.php?f=7&t=33391

||OS||Archlinux i686 with kernel 2.6.34.1||
||VirtualBox||PUEL v3.2.6||"	defect	closed	other	VirtualBox 3.2.6	fixed			other	Linux