BenV's notes

Yay, another new linux kernel. Of course this broke the closed NVidia driver, I tried 331.38:

[ 110.917769] nvidia: Unknown symbol acpi_os_wait_events_complete (err 0)

The fix for this is easy, unpack the installer and then patch file kernel/nv-acpi.c hack out line 306:

// NV_ACPI_OS_WAIT_EVENTS_COMPLETE();

Run nvidia-installer and you should be good to go. Incredible that it always takes NVidia forever to fix these things, this bug has been known since at least 3.13-rc1. Oh well.

Next up, testing nftables. Looks like iptables will soon be obsolete 🙂
Here’s a nice howto to get you started – https://home.regit.org/netfilter-en/nftables-quick-howto/.
Update:
Might you be wondering (like me) where the heck the libnftables git repository went: they decided to rename the thing to libnftnl. You can find the repository here – https://git.netfilter.org/libnftnl/

Another thing: compiling nftables from git breaks on my Slackware64-current machine atm because 1. configure.ac still points to libnftables (instead of libnftl), I assume this will be fixed within the hour. 2: it tries to compile against libreadline without linking libncurses.
Fix for that is running configure like: LDFLAGS=-lncurses ./configure

Good news everyone! Linux 3.8 has been released! Obviously I immediately fired up my compiled to upgrade from the by now ancient 3.6.8 kernel that I was running.
After rebooting my Slackware64 machine into the new kernel without a problem it was time to recompile the NVIDIA binary blob. You know, this piece of garbage. It doesn’t matter if you pick the latest official release version (seems to be 310.32 atm) or the beta that I picked, it won’t compile.
Running the installer will fail and leave you a /var/log/nvidia-installer.log that contains something like this:

root@machine:/# tail /var/log/nvidia-installer.log
/tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv.c: In function ‘nv_kern_open’:
/tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv.c:1521:30: warning: passing argument 2 of ‘request_irq’ from incompatible pointer type [enabled by default]
In file included from /tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv-linux.h:128:0,
from /tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv.c:13:
include/linux/interrupt.h:130:1: note: expected ‘irq_handler_t’ but argument is of type ‘enum irqreturn_t (*)(int, void *, struct pt_regs *)’
/tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv.c:1525:17: error: implicit declaration of function ‘NV_TASKQUEUE_INIT’ [-Werror=implicit-function-declaration]
/tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv.c:1537:25: warning: passing argument 2 of ‘request_irq’ from incompatible pointer type [enabled by default]
In file included from /tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv-linux.h:128:0,
from /tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv.c:13:
include/linux/interrupt.h:130:1: note: expected ‘irq_handler_t’ but argument is of type ‘enum irqreturn_t (*)(int, void *, struct pt_regs *)’
cc1: some warnings being treated as errors
make[3]: *** [/tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel/nv.o] Error 1
make[2]: *** [_module_/tmp/selfgz7139/NVIDIA-Linux-x86_64-313.18/kernel] Error 2
NVIDIA: left KBUILD.
nvidia.ko failed to build!
make[1]: *** [module] Error 1
make: *** [module] Error 2
-> Error.
ERROR: Unable to build the NVIDIA kernel module.

Fortunately here’s a little patch you can run to fix it. This assumes you have your linux 3.8 kernel sources symlinked in /usr/src/linux!

root@machine:/usr/src# wget -q ftp://download.nvidia.com/XFree86/Linux-x86_64/313.18/NVIDIA-Linux-x86_64-313.18.run
root@machine:/usr/src# bash NVIDIA-Linux-x86_64-313.18.run -x
root@machine:/usr/src# cd NVIDIA-Linux-x86_64-313.18
root@machine:/usr/src/NVIDIA-Linux-x86_64-313.18# wget -q http://notes.benv.junerules.com/wp-content/uploads/2013/02/nvidia-313.18-linux-3.8.patch
root@machine:/usr/src/NVIDIA-Linux-x86_64-313.18# patch -p1 < nvidia-313.18-linux-3.8.patch root@machine:/usr/src/NVIDIA-Linux-x86_64-313.18# ./nvidia-installer # now it should work
Works for me at least 😉

Yesterday I wrote a post on NVIDIA and how they (mis)handle RGB channels over HDMI on windows by default (and also how to fix it of course). Here’s the post on NVIDIA’s HDMI handling.
Today I figured Let’s check out if I can find my post if I Google for BenV NVIDIA.

Check out the results…. yes, I wrote about NVIDIA earlier, January 29th. However, normally the day after (often even faster, say an hour after) writing writing a post I can find it with Google using the keywords BenV and another word in the title. For example BenV Steam is on the 4th place, posted on the same day. But the post on NVIDIA from that same day IS NOWHERE TO BE FOUND.
I wonder how much Google are being paid to not show the links that connect NVIDIA to negative things.

Funny how Google can spend resources to conveniently downrank my post (and obviously also other negative ones), but if Mr Smith sues Google because whenever someone types “Smith” Google suggests “pedophile” as second keyword then Google claims it’s all out of their control and that’s just the algorithm.
I hope you get sued again Google, you deserve it.

Before today I was still working behind an old 20″ 2006 Acer (al2016W) as primary screen and an even older 17″ secondary screen.
They started to bug me a bit, and after looking around a bit for new screens I ordered 4 new instances of the BenQ GW2450HM.
After reading a very positive review at TFTCentral on the BenQ GW2450HM and
also a forum that was a lot more negative (people who died because of ghosting issues etc) I decided to buy them anyway because they couldn’t possibly
be worse than my current screen.

Today they arrived, so after unpacking them and figuring out how the heck I was going to make space for them on my desk I finally connected them to my PC.
I had windows up and running, which immediately noticed the BenQ that was connected through HDMI. The BenQ happily told me “No Cable Connected” however, but that
was solved by hitting the enter button twice to make it use the HDMI as source instead of the ancient DSUB. They should really stop supplying those connectors.

After unpacking and installing the second screen and connecting it to DVI I noticed a difference.
Both had the same background, but the DVI screen had deeper blacks than the HDMI one!
Nope, it’s not caused by the brightness or any of those knobs, they were identical (factory default) on both screens.

The reason for this is simply: NVIDIA sucks. Hm, that’s a nice trademark that they should register 😉
Yeah, those incompetent assholes again. NVIDIA (sucks) doesn’t care if your left screen looks a bit brighter than your right screen. They only care about getting your money, which is strange because actions like these make it less likely that they’ll receive my money in the future.

Some background on the issue:
When you connect a HDMI device to a NVIDIA (sucks) graphics card, the NVIDIA (sucks) assumes that the device is crippled and can only handle RGB values between 16-235.
Obviously PC monitors can handle the full range of 0-255, which is the default on VGA and DVI. (this is the reason my DVI screen was darker).
This mismatch in communication will fuck up the black colors for starters, but for a real impression check out this forum: http://www.neogaf.com/forum/showthread.php?t=471695
Mind you that the control panel settings that they discuss in that thread didn’t work for me.

Fortunately there’s a solution that does work for me.
This guy over here at metaclassofnil.com wrote a tiny tool to fix your registry and tell the driver to use the full range.
After a reboot everything looks great on BOTH screens 🙂

While updating wine-1.4-rc1 I thought it would be interesting to see if I could get their OpenCL stuff to work. The lack of information on how to do so is really annyoing, so here’s what I did to get it to compile. (continue reading…)

Or… not. Oh, the pokemon reference comes from the brilliant webcomic XKCD.

Usually I have little problems getting stuff to work on it, but as hardware gets older and support gets worse thing get more interesting.
First things first: I have no issues with ubuntu, they’re doing great work. In fact, the machine worked fine after installation, except for I can’t live with 800×600, so I wanted a better video driver.
Needless to say that means NON OPEN SOURCE GARBAGE FROM NVIDIA (ATI is just as bad btw). Although their binary driver usually ‘works’, you’re royally screwed if your system doesn’t meet their requirements. (continue reading…)