For the confirmation, I'd need guidance. Which source/mutter link to click to reinstall the prior version (or is it all of them?).
Since writing the above report, by reflex more Ubuntu updates have been accepted (there have been very many this week - perhaps four or five) - new dpkg.log attached. After each new update the resolutions and frequencies sent to both monitors were correct; without problem. This morning, monitor 2 (the new one) followed the boot sequence in a mode I've never seen before - all pink and at ordinary HD 1920 (it seems). Then it went blank for half a second. Then it put up the usual message that it was changing to 4K at 30 Hz, then the desktop came up fine. [Coincidentally, an email arrived that bug 1714178 (and my bug duplicate 1795439) have been fixed (released) to overcome the modesetting driver 8192x8192 limitation. I may try again using three 4K horizontal monitors - when the third is repaired. Are the patchset and merge to drm-tip before or after this particular incident?]. I feel to add (by experience) that the former damaged monitor 2 was perhaps more vulnerable than most to sudden fast mode changes. With a previous PC (ubuntu 16.04) with Intel HD600, that monitor had to receive a valid mode at a very specific moment (which meant the user had to learn to push on the power buttons precisely one second apart) else the monitor would revert immediately to high Hz modes at inferior resolutions or shut down. With this configuration Intel HD620 and Ubuntu Bionic Beaver, both monitors can be on, will move to sleep mode and wait - great! The user can switch on the PC when they're ready. Just to say that, perhaps monitor 2 was vulnerable to even a blip at 60Hz. On the other hand, that doesn't explain how monitor 1 found itself attempting 4096 which is also part of this bug report. Can I still help in confirmation work by going back to the prior version? ** Attachment added: "dpkg.log" https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1828665/+attachment/5266146/+files/dpkg.log -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1828665 Title: [regression] Reboot after dpkg update set invalid Graphics resolutions (Dual Monitor) since ~7th/8th May To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1828665/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
