difference between rd.driver.blacklist and modeset=0

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ron7000
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difference between rd.driver.blacklist and modeset=0

Post by ron7000 » 2019/01/15 22:20:59

regarding best way to disable nouveau at viewtopic.php?t=68800

something like this is done to pass either rd.driver.blacklist or nouveau.modeset=0 as a kernel parameter.

Code: Select all

GRUB_CMDLINE_LINUX="rhgb verbose rd.driver.blacklist=nouveau nouveau.modeset=0"' 
This then allows one to install the NVidia graphics driver.

My questions are, what's the difference between the two, is both needed, and what does either do technically?

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TrevorH
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Re: difference between rd.driver.blacklist and modeset=0

Post by TrevorH » 2019/01/16 00:49:38

Using rd.driver.blacklist= tells dracut not to automatically load the nouveau driver even if it finds the machine has hardware present on it that the nouveau module claims to support. That should stop nouveau from loading.

Using nouveau.modeset=0 is telling the nouveau driver when it loads, not to issue a modeset. Theoretically, if you have the first one specified, this one should never be needed but I guess it doesn't hurt just in case some sysadmin issues modprobe nouveau which would load it even if it was blacklisted.

Really the best way is to use the ELRepo kmod-nvidia packages as they do it all for you.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

ron7000
Posts: 162
Joined: 2019/01/15 20:00:28

Re: difference between rd.driver.blacklist and modeset=0

Post by ron7000 » 2019/01/17 14:28:09

I jumped ship from Suse/SLES, using RHEL & CentOS now. Back on SLES I didn't have nouveau trouble like I seem to be having now with the "Nvidia driver can't install because nouveau..".

Here's what I do now
  • 1. start Centos 7-1810 install from DVD, it installs, system comes back up on my 1920x1200 or 2560x1440 monitor no problem, this is with having an Nvidia p620 (or GTX970) installed and monitor working off that graphics card via dvi-d or displayport.
  • 2. download nvidia###.run file, do an init 3, launch nvidia.run file and get the nouveau error cannot proceed.
  • 3. modify /etc/default/grub and append GRUB_CMDLINE_LINUX with "rd.driver.blacklist=nouveau modprobe.blacklist=nouveau nouveau.modeset=0". Didn't take any chances, threw everything at it, I guess all that's really needed then is rd.driver.blacklist=nouveau.
  • 4. grub2-mkconfig -o /boot/efi.../grub.cfg
  • 5. dracut -f /boot/initramfs-$(uname -r).img $(uname -r)
  • 6. reboot, init 3, nvidia.run installs without nouveau error, system now works with nvidia graphics (and cuda) drivers.
between step 1 and 2 then, do I need to manually look for kmod-nvidia from EPEL (extra packages for enterprise linux) ?
I am already registering to EPEL after step 1, and it would be easier to just install kmod-nvidia if that's all that's needed rather than going through the hassle of steps 3 and 4 before installing nvidia.run. thanks.

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TrevorH
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Re: difference between rd.driver.blacklist and modeset=0

Post by TrevorH » 2019/01/17 15:52:10

It's not EPEL, it's ELRepo. They specialise in support for hardware that isn't included in RHEL and one of the things they package is the nvidia proprietary driver. They do that in a way that means you do not have to rebuild/reinstall the nvidia driver after every kernel update and also you don't have to worry about blacklisting etc as they do it all for you. It's the recommended way to use the nvidia proprieteary driver on RHEL/CentOS. Your 6 step process then becomes

1) Install from DVD
2) install elrepo-release-rpm
3) install kmod-nvidia
4) get on with life
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

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