Cannot login after long AFK at lock screen with monitor off

Issues & Assistance
1

Hi there,

I installed CachyOS ~1 week ago, and did not updated or turned off my computer for a week. And during the week, I used my computer as usual, where I would just lock the desktop (meta+L) and then turn off my monitor (with the power button of the monitor) if I need to leave the computer. The reason I don’t turn my computer off (or let it sleep) is because I usually have to run some long lasting jobs (e.g. machine learning).

A two days ago, I finally decided to update and reboot my system. It seems like multiple things have updated at the same time: nvidia driver, plasma, the kernal, etc. After the update, I noticed that when I power on/off my monitor, the system would play a “system bell” sound (the same sound you would hear when you plug in an USB device), which was not the case before I update the system.

This may not be related to my main issue. The issue was that if I lock my screen and power off my screen for a long time (e.g. >10 mins), when I come back, turn back on my screen, enter my password, and hit enter, nothing would happen: no black screen, would no enter plasma, even clicking “>” button next to the password box would not do anything either. However, if I click “Switch User”, it would go to the login screen (SDDM). If I enter my password there, it would give me a black screen and my monitor would say there’s no signal.

Note that this does NOT happen, if I lock my screen, turn off my monitor for a SHORT time (say ~1 min) and turn it back on, it would enter plasma if I enter my password from the lock screen (the system bell sound would still play).

The reason why I mentioned the “system bell” sound when I power on/off my monitor is that I am guessing that maybe plasma “disconnects” my monitor when I powered it off, and after a long AFK, plasma “cannot find” my monitor anymore so that’s why it lost its signal… I could be completely wrong and it could just be a stupid nvidia driver thing…

Again, this was NOT the behavior before the update, I would not hear the “system bell” sound, neither was there any issue with login after long AFK.

Some extra information that may help pinpoint the issue:

  • Kernal: 6.11.4-2-cachyos
  • Nvidia-driver: 560.35.03-16
  • Plasma: 6.2.1.1-1.1

If anyone has any insight about this issue, it would be greatly appreciated. Thank you in advance.

2

Based on the OP, it looks like you can access the system, so the next step would be to enter TTY3 (CTRL + ALT + F3) and try running startplasma-wayland. Getting some logs would be helpful too sudo cachyos-bugreport.sh

3

Thanks for the quick response. And yes you are right, I was able to enter different TTYs, including TTY3. I did not know about the command startplasma-wayland but I will try it next time I encounter this issue.

For the logs, should I run sudo cachyos-bugreport.sh before the issue happens, or after? (Sorry for the stupid question.)

4

You should run it after.

5

Thanks again for your patience and assistance on helping me out.

I found a work-around to my problem, where I could “turn off screen” (it’s actually making the monitor go to sleep) immediately after lock, in System Settings → Power Management:

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This does not “disconnect” my monitor (no system bell played) when I lock my screen. And I don’t need to use the power button on my monitor in this way. I just need to make sure I don’t accidentally move my mouse that wakes up the screen.

6

Update: My previous work-around did not solve the problem, it happened again just now: I left my PC locked for >2 hours, and again, cannot enter plasma when I enter my password.

I switched to TTY3 and ran sudo cachyos-bugreport.sh. Wiredly, when I ran the command, TTY3 also lost monitor signal, but when I switched back to TTY2, it entered the plasma desktop…

Nevertheless, I was able to obtain the bug report from where I ran the command. Due to word limit and file upload limitation here, I uploaded the log file to my github, if you would like to take a look: cachyos-bugreport.log

Hope this is useful. Thanks in advanced for any help you could offer.

7

I am pretty sure that this issue and the one in this topic Black screen after display disconnection (wayland + nvidia) are very related, if not the same issue. Hence I am very interested if we can glean something from the logs here.

8

Not sure if it is exactly the same issue or not but when I come back to my idling system and the monitor has turned off (not sleeping), I have to make multiple attempts to login in until I can. Entering the password correctly does nothing and the enter icon beside the password field can be clicked but does nothing. I hit Esc to darken the screen and Esc again, try again to use password, same prob. I keep doing this until I get a double login which finally works. This only happens when I’ve been away from my PC for a long time.

OS: CachyOS Linux x86_64
Kernel: Linux 6.11.6-2-cachyos
DE: KDE Plasma 6.2.2
WM: KWin (Wayland)
WM Theme: Breeze
(All AMD system; CPU, iGPU and dGPU)

9

Sorry, I thought no one was onto this issue therefore I deleted the log files in my previous pose. I reloaded two bug reports when it happened in other times. If this is in any way helpful: bug reports

I am not sure if this is the best way to share bug reports, please let me know other wise.

10

This is the exact same issue I am having. I honestly thought it was an nvidia problem. Hearing your case, it apparantly is also happening on AMD systems.

11

Still having this problem? I also tried a system update but I don’t think that’s the issue. I installed CachyOS using the default options when choosing packages (trying more than that was failing), and I had this issue both before and after I started installing more into the system so I don’t think I did anything to bork it. My screen is 120Hz if that matters. :sweat_smile:

12

I have a 240Hz monitor but locked at 120Hz. I haven’t done any extensive testing, but I haven’t recalled the same issue happening in the past week. I don’t know if any updates actually fixed the problem, or if it’s just luck.

13

As long as I make sure not to bring my screen to life with my mouse and use keyboard instead, it solves the issue. It’s a mouse-related wake up issue perhaps?

14

You might be onto something here. I do love to use my mouse to wake the screen, and I am also using a Razer wireless mouse (not sure if this matters).

Honestly, I think the real issue here is that it seems random and I cannot reliably reproduce it. It did happen to me again yesterday (after an update), but I forgot to generate the bug report. It might be a KDE issue since no driver or kernal update yesterday but I saw a bunch of KDE related packages getting updated.

15

Ok, I jinxed it. It now happens even if I use the keyboard to wake up my screen. :sweat_smile:

16

I have the same problem for about a month, I move away from the pc, minutes pass, the screen locks, a while later the monitor turns off (so far so normal because it has always been), let’s say I leave the PC like this for an hour or two, I come back and move my mouse, the screen turns on, it asks me for a password, I enter it, I press enter and it doesn’t unlock, I press enter repeatedly, and suddenly it pretends to unlock, but no, it’s the login screen that has been reset (the profile image that was round is now square) and it asks me for the password again and this time it does unlock. I have an AMD RX 6000 GPU.

17

Yeap, same problem as me. I gave up on the auto-lock and disabled it. I still have the screen turn off, but disabled the auto lockscreen. Locking the screen manually does not cause this bug (so far… touch wood).

18

Interesting, I guess I have not pressed enter enough times. Sometimes I find the lock screen would reset if I ctrl+alt+f1/2/3 to switch between sessions and back, but most times it doesn’t. This is my main issue with it, it’s not consistent. Sometimes, this problem happens when I lock my screen for 10 mins, and other times, it will survive tens of lock/unlock in days without any issues. It’s just a total myth to me.

19

I really wish you did not jinx it again, since I have always manually lock my screen… (Of course, this leads to the problem I posted)

I have since changed my habbit to NOT lock the screen and simply turn off my monitor. Haven’t encountered this problem again, but it could just be some updates to the kernal or nvidia driver or KDE.