Ubuntu 22.04.2 LTS
5.19.0-32-generic #33~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Mon Jan 30 17:03:34 UTC 2 x86_64 x86_64 x86_64 GNU/Linux
For a long time I've been able to do sudo systemctl hibernate
and have my laptop (Dell XPS17) go into hibernation mode. Usually it takes a few seconds, the screen blanks, and then the keyboard backlight goes off and the machine is basically "off" until I wake it up later.
Recently, something has changed, maybe something that was installed as part of system maintenance, and now hibernate does something weird.
When I issue the command, it does what it usually does, the screen then goes blank, and then about a second later the screen returns to what it was showing, with the same backlight level, but the mouse cursor is frozen (or missing), and the keyboard is non-responsive. It's like the machine is in hibernate, but the screen didn't turn off.
If I hold the power button for ~10 seconds, it powers off the screen, but the weird thing is that when I power it back on later, it's as if it had hibernated - I get back to where I was, rather than a cold boot.
So I'm thinking something has changed in the way the screen is handled - any ideas?
I tried with a Linux virtual console and the same thing happens - the blinking cursor stops after a few seconds but the screen remains on.
Here's my dmesg after a sudo systemctl hibernate
:
[82037.130237] PM: hibernation: hibernation entry
[82037.136832] Filesystems sync: 0.005 seconds
[82037.136836] Freezing user space processes ... (elapsed 0.002 seconds) done.
[82037.139194] OOM killer disabled.
[82037.139449] PM: hibernation: Marking nosave pages: [mem 0x00000000-0x00000fff]
[82037.139452] PM: hibernation: Marking nosave pages: [mem 0x0009f000-0x000fffff]
[82037.139454] PM: hibernation: Marking nosave pages: [mem 0x5aa9f000-0x5aa9ffff]
[82037.139455] PM: hibernation: Marking nosave pages: [mem 0x5aaae000-0x5ab26fff]
[82037.139457] PM: hibernation: Marking nosave pages: [mem 0x5abd8000-0x5abd8fff]
[82037.139458] PM: hibernation: Marking nosave pages: [mem 0x5f77a000-0x63ffefff]
[82037.139656] PM: hibernation: Marking nosave pages: [mem 0x64000000-0xffffffff]
[82037.140818] PM: hibernation: Basic memory bitmaps created
[82037.141791] PM: hibernation: Preallocating image memory
[82041.930053] PM: hibernation: Allocated 3200064 pages for snapshot
[82041.930055] PM: hibernation: Allocated 12800256 kbytes in 4.78 seconds (2677.87 MB/s)
[82041.930057] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[82041.932177] printk: Suspending console(s) (use no_console_suspend to debug)
[82044.109104] ACPI: EC: interrupt blocked
[82044.128094] ACPI: PM: Preparing to enter system sleep state S4
[82044.144776] ACPI: EC: event blocked
[82044.144778] ACPI: EC: EC stopped
[82044.144779] ACPI: PM: Saving platform NVS memory
[82044.152148] Disabling non-boot CPUs ...
[82044.154299] smpboot: CPU 1 is now offline
[82044.159695] smpboot: CPU 2 is now offline
[82044.161962] smpboot: CPU 3 is now offline
[82044.164446] smpboot: CPU 4 is now offline
[82044.166920] smpboot: CPU 5 is now offline
[82044.169465] smpboot: CPU 6 is now offline
[82044.171983] smpboot: CPU 7 is now offline
[82044.176620] smpboot: CPU 8 is now offline
[82044.178608] smpboot: CPU 9 is now offline
[82044.180314] smpboot: CPU 10 is now offline
[82044.182275] smpboot: CPU 11 is now offline
[82044.184166] smpboot: CPU 12 is now offline
[82044.186001] smpboot: CPU 13 is now offline
[82044.187809] smpboot: CPU 14 is now offline
[82044.190045] smpboot: CPU 15 is now offline
[82044.191935] PM: hibernation: Creating image:
[82044.496503] PM: hibernation: Need to copy 3159714 pages
[82044.496505] PM: hibernation: Normal pages needed: 3159714 + 1024, available pages: 5158353
Update July 2023
Selecting the 5.15.0-75-generic kernel works around this problem. Now, when hibernate is initiated, the screen goes blank for 10-20 seconds, then briefly displays again, and then the laptop powers off properly. Waking up from hibernation is a bit slower, with the screen remaining blank for ~30 seconds, but it's all working.
I have only tried alternating between 5.15 and 5.19, so I'm not sure which version introduced this regression, but based on other comments I've seen, it seems likely to have been introduced in 5.16.