kmod-nvidia vs akmod-nvidia

dth4h · #1 19th August 2009, 02:34 AM

What is the difference between kmod-nvidia and akmod-nvidia. And which one should I use?

This is my nvidia video card: nVidia Corporation GeForce 8200M G (rev a2)

ozjd · #2 19th August 2009, 03:07 AM

This seems to get asked every couple of weeks.

kmod is the driver. It is made for a particular kernel. When a new kernel is released you need a new kmod. It sometimes takes a few days for the new kmod to appear.

akmod will create the driver for the kernel being loaded so you don't have to wait for a new kmod when the kernel is updated. It is a simpler way. I would recommend akmod, that is what I have been using. See the nvidia thread in my signature.

***Hlingler*** · #3 19th August 2009, 04:50 AM

A 'kmod' (kernel driver module) is the pre-compiled, low-level software interface between the kernel and a driver. It gets loaded (into RAM) and merged into the running kernel. Linux kmods are specific to one and only one kernel, and will not work (nor even load) for any other kernel. Advantages: Pre-Compiled - no need to fool around with compiling, compilers, *-devel packages and other associated overhead. Disadvantages: updating and re-booting into a new kernel without updating the kmod(s) will result in loss of functionality (e.g.: 3D video support) at best, or worse (e.g.: X11 crashes/freezes); inherent delays in updating kmods after kernel updates.

But 'akmods' is a system (like DKMS) to auto-build (hence: akmod) new kmods for you "on-the-fly", in response to new/changed running kernel. Advantages: obvious. Disadvantages: HDD space required for compilers and *-devel packages; unforseen/uncorrectable driver problems that cannot be resolved by the automatic tools.

The actual Linux driver(s) itself (2D, and often also 3D; in this case: NVidia video driver) is actually a separate file (nvidia_drv.so).

HTH,
V

AlFrugal · #4 19th August 2009, 06:56 PM

I'm running FC11. I use the nvidia driver from RPMFusion. I just installed the kernel upgrade from 2.6.29.6-217.2.3.fc11.i686.PAE to 2.6.29.6-217.2.8.fc11.i686.PAE. As has been noted in several threads on Fedoraforum, the kmod-nvidia driver that matches this latest kernel has not yet been released. So, as recommended in several of the threads, I installed akmod-nvidia.i686. I did *not* remove any of the currently installed kmod-nvidia modules.

After installed akmod-nvidia, I rebooted to the latest kernel. akmod appeared to furnish the needed kmod-nvidia for the latest kernel, but my boot then hung when trying to start X-Window. I tried rebooting the latest kernel and the same thing happened.

I am able to boot the fallback kernel 2.6.29.6-217.2.3.fc11.i686.PAE. Running under this kernel, I ran Yum extender and looked into deleting all of my installed kmod-nvidia modules (as has been recommended in several of the posts here). I also selected for delete vanilla kmod-nvida. I didn't go through with this deletion because Yum selected for deletion a bunch of other modules for dependencies such as akmod-nvidia and some X-Window modules.

What exactly am I supposed to do so that my kernel 2.6.29.6-217.2.8.fc11.i686.PAE will boot using akmod-nvidia?

(Leigh's Fedoraforum nvidia Howto and the Fedorasolved akmod Howto don't say anything about having to delete any kmod-nvidia* modules).

***Hlingler*** · #5 19th August 2009, 08:20 PM

Theoretically, you should be able to have BOTH kmod-* and matching akmod-* installed without any ill effects. If a current/necessary kmod is not found, then (as you have seen) akmod should build one, and it should be (functionally if not exactly/literally) identical to a pre-compiled kmod. Practically, I cannot say for certain if this might cause problems. Personally: I consider the kmod-* RPMs to be unnecessary at best, if matching akmod-* is installed, and there may also be administrative problems.

You can try to forcibly remove the kmod-nvidia RPMs, AT YOUR OWN RISK of course; this may necessitate re-install of akmod-nvidia and/or other NVidia driver bits. If you want to try:
su -
rpm -ev --nodeps kmod-nvidia<insert-version-release> << also add any other kmod-nvidia*
yum reinstall akmod* xorg-x11-drv-nvidia*
reboot

However... I suspect that this will not solve the video driver problem. Or maybe it will. Alternatively, I have been suggesting to use instead Leigh's DKMS-based driver (see Post #4 of his NVidia Guide), but no one seems to want to try.... Note that the DKMS-based driver requires that you first uninstall all other NVidia driver bits & associated RPMs. Leigh also has made an NVidia beta driver (190.18?) RPM for this driver - it's floating around here somewhere....

Theoretically, all these drivers - whether from NVidia Corp. binary, kmods, akmods, DKMS - should function identically, assuming the same base NVidia driver version. Practically: it doesn't work out that way. Personally: I prefer the DKMS-based driver, for a number of reasons.

Good Luck,
V

LinuxDanP · #6 19th August 2009, 08:37 PM

I've installed akmod-nvidia on my Fedora 11 64-bit computer, and made the correct edits to xorg.conf. When I then run startx, it fails to start the X server. From looking at the error log it can't find nvidia.ko. What's with that? And what's a .ko file?

***Hlingler*** · #7 19th August 2009, 08:56 PM

Quote:

And what's a .ko file?

A kmod (loadable kernel driver module) - see Post # 3 above.

Quote:

From looking at the error log it can't find nvidia.ko. What's with that?

Not sure; try:
su -
updatedb
locate nvidia.ko

Post results.

V

LinuxDanP · #8 19th August 2009, 09:12 PM

I tried both updatedb and locate, and neither command can be found. What package do I need to install to get those?

***Hlingler*** · #9 19th August 2009, 09:47 PM

yum install mlocate

Can't believe it's not there by default, but....

V

Iron_Mike · #10 19th August 2009, 10:12 PM

Quote:

Originally Posted by LinuxDanP

I tried both updatedb and locate, and neither command can be found. What package do I need to install to get those?

Maybe, maybe not. The command is:

su space hyphen

Then try it again.

Mike

LinuxDanP · #11 20th August 2009, 12:38 AM

Permissions shouldn't have been the problem. I'm running the computer from root, and kde isn't working (I was told to get the graphics drivers working may be a problem) so I'm left without a desktop system.

LinuxDanP · #12 20th August 2009, 12:42 AM

Locate nvidia.ko came up with nothing. I also verified that I had installed akmod-nvidia, it is installed and the latest version. (I installed it yesterday.)

***Hlingler*** · #13 20th August 2009, 12:51 AM

The kmods should have been built as part of the RPM installation, but you can force. Try:
su -
akmods --kernels `uname -r`

Copy-and-paste command to get the funky characters.

Re-start of X (or re-boot) required.

V

P.S. The akmods system requires compilers and kernel-devel to build the kmods. These should have been dragged in as deps, but.... Check:
yum install gcc make kernel-devel kernel-headers

ought to do it.

LinuxDanP · #14 20th August 2009, 01:32 AM

Ok, I already had gcc etc. and when I ran akmods --kernels `uname -r` it said it was checking kmods, then it tried to build kmod-nvidia and failed. I also tried running

akmods --force with the same result.

***Hlingler*** · #15 20th August 2009, 01:39 AM

OK, please post:
su -
lspci|grep VGA
uname -r
rpm -q kernel kernel-devel kernel-headers|sort
rpm -qa|grep -i nvid|sort

Was there a message about a log file to consult? If so, check it, and if necessary attach to a post so we can see what went wrong.

V

P.S. By any chance: have you ever previously installed the NVidia binary on this OS ?