Graphical Environments & Desktops • second display not working on imac after debian bookworm upgrade

I changed /etc/default/grub lines
#GRUB_CMDLINE_LINUX_DEFAULT="text"
#GRUB_CMDLINE_LINUX="radeon.modeset=0"
GRUB_CMDLINE_LINUX_DEFAULT="line"

Why "line"?

I also tryed this:
#GRUB_CMDLINE_LINUX="radeon.modeset=0"
GRUB_CMDLINE_LINUX_DEFAULT="text"
GRUB_CMDLINE_LINUX="line"

Why "text"?

If I change line into /boot/refind.conf:
from "Boot with standard options" "root=UUID=484c9fc9-bcf0-4a34-941c-5b513893d3c1 ro nomodeset"
to "Boot with standard options" "root=UUID=484c9fc9-bcf0-4a34-941c-5b513893d3c1 ro line"
main display turns to black during booting process, and second monitor always black. If I remove cable of second monitor, main monitor shows the booting process untill running properly.

Again, what is "line" supposed to do?

You've gained ground by proving you can get rid of nomodeset. Now focus needs to goto a way to solve the black screens problem. We need to see the content of Xorg.0.log produced from a boot without using nomodeset. So, boot with both displays connected and without nomodeset. When boot finishes, disconnect one display, and use the other to capture the current Xorg.0.log showing that boot was done without using nomodeset, and attach it to your reply here. Do not paste it into your reply.

Note that most of the time, there will be also an Xorg.0.log.old wherever Xorg.0.log is found. Either can be acceptable if the Kernel command line: in the file contains the required parameters and omits the parameters to be excluded. It sometimes happens that an initial X failure is shortly followed by an automatic retry, which causes the two to be nearly identical, so that if one is useless, so is the other.

There is anything related to the refind setting?

As long as you're interested in having more than one display working, refind should have no relevance to any solution.

Code:

$ inxi -GSIaz...    parameters: root=UUID=484c9fc9-bcf0-4a34-941c-5b513893d3c1 ro nomodeset...

and this is the /var/log/Xorg.pid-1054.log

Code:

...[    32.558] Kernel command line: root=UUID=484c9fc9-bcf0-4a34-941c-5b513893d3c1 ro nomodeset text initrd=boot\initrd.img-6.6.15-amd64...

As explained in comment #8, including nomodeset on the kernel command line prevents more than one display at a time from being used. As long as your goal is using two displays, you must find a way to exclude it from your kernel cmdlines. If it's still included in /etc/default/grub, your need to purge it. Nomodeset should only be included:

• when required to capture information from a previous boot
• when required to make configuration and/or software changes to fix broken normal booting
• when a proprietary driver's installation instructions necessitates
• when you absolutely must use the the computer and can tolerate having only one working display at low resolution to do so

Edits to /etc/default/grub and subsequent grub.cfg regeneration should be reserved for when changes to be made are expected to be permanent. When testing, each boot should be started using the E key at the Grub menu to configure boot parameters as required for that particular test boot being initiated. At the very least you should restore GRUB_CMDLINE_LINUX= to what it contained to start with, which keeps recovery mode boot stanzas in grub.cfg capable of doing their jobs.

Statistics: Posted by mrmazda — 2024-04-03 23:27 — Replies 10 — Views 1461

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