Hibernation does not work with 5.7, works with 5.6 and 5.8 (RC5)

Hi,

hibernation (systemctl hibernate) does not work for me on 5.7.9-1-MANJARO, i.e.
the screen turns black, but the mouse cursor is still there (but frozen) and after a few seconds the login screen (SDDM) comes back.

dmesg -w says:

[90276.464827] PM: hibernation: hibernation entry
[90276.478654] Filesystems sync: 0.008 seconds
[90276.478656] Freezing user space processes ... (elapsed 0.004 seconds) done.
[90276.483490] OOM killer disabled.
[90276.483641] PM: hibernation: Marking nosave pages: [mem 0x00000000-0x00000fff]
[90276.483644] PM: hibernation: Marking nosave pages: [mem 0x00058000-0x00058fff]
[90276.483645] PM: hibernation: Marking nosave pages: [mem 0x0009d000-0x000fffff]
[90276.483647] PM: hibernation: Marking nosave pages: [mem 0x40000000-0x403fffff]
[90276.483662] PM: hibernation: Marking nosave pages: [mem 0x4f2c1000-0x4f2c2fff]
[90276.483663] PM: hibernation: Marking nosave pages: [mem 0x4ff1d000-0x4ff1dfff]
[90276.483664] PM: hibernation: Marking nosave pages: [mem 0x9503d000-0x9503efff]
[90276.483665] PM: hibernation: Marking nosave pages: [mem 0x98609000-0x98708fff]
[90276.483670] PM: hibernation: Marking nosave pages: [mem 0x9e988000-0x9fffefff]
[90276.483751] PM: hibernation: Marking nosave pages: [mem 0xa0000000-0xffffffff]
[90276.484952] PM: hibernation: Basic memory bitmaps created
[90276.485257] PM: hibernation: Preallocating image memory
[90279.316162] PM: hibernation: Allocated 1466394 pages for snapshot
[90279.316164] PM: hibernation: Allocated 5865576 kbytes in 2.83 seconds (2072.64 MB/s)
[90279.316165] Freezing remaining freezable tasks ... 
[90299.323122] Freezing of tasks failed after 20.007 seconds (0 tasks refusing to freeze, wq_busy=1):
[90299.323128] Showing busy workqueues and worker pools:
[90299.323133] workqueue events_freezable_power_: flags=0x86
[90299.323135]   pwq 8: cpus=0-3 flags=0x4 nice=0 active=1/0 refcnt=3
[90299.323143]     in-flight: 174130:disk_events_workfn
[90299.323176] pool 8: cpus=0-3 flags=0x4 nice=0 hung=0s workers=5 idle: 176381 177254 178933 175229
[90299.323399] Restarting kernel threads ... done.
[90299.459201] acpi LNXPOWER:02: Turning OFF
[90299.459236] acpi LNXPOWER:01: Turning OFF
[90299.459694] PM: hibernation: Basic memory bitmaps freed
[90299.459695] OOM killer enabled.
[90299.459696] Restarting tasks ... done.
[90299.489751] PM: hibernation: hibernation exit

However, on 5.6.19-2-MANJARO it works:

[   49.661089] PM: hibernation: hibernation entry
[   49.666538] Filesystems sync: 0.004 seconds
[   49.666543] Freezing user space processes ... (elapsed 0.003 seconds) done.
[   49.669697] OOM killer disabled.
[   49.669811] PM: hibernation: Marking nosave pages: [mem 0x00000000-0x00000fff]
[   49.669813] PM: hibernation: Marking nosave pages: [mem 0x00058000-0x00058fff]
[   49.669813] PM: hibernation: Marking nosave pages: [mem 0x0009d000-0x000fffff]
[   49.669815] PM: hibernation: Marking nosave pages: [mem 0x40000000-0x403fffff]
[   49.669826] PM: hibernation: Marking nosave pages: [mem 0x4f2c1000-0x4f2c2fff]
[   49.669827] PM: hibernation: Marking nosave pages: [mem 0x4ff1d000-0x4ff1dfff]
[   49.669827] PM: hibernation: Marking nosave pages: [mem 0x9503d000-0x9503efff]
[   49.669828] PM: hibernation: Marking nosave pages: [mem 0x98609000-0x98708fff]
[   49.669831] PM: hibernation: Marking nosave pages: [mem 0x9e988000-0x9fffefff]
[   49.669891] PM: hibernation: Marking nosave pages: [mem 0xa0000000-0xffffffff]
[   49.670823] PM: hibernation: Basic memory bitmaps created
[   49.670934] PM: hibernation: Preallocating image memory
[   50.126363] PM: hibernation: Allocated 780786 pages for snapshot
[   50.126365] PM: hibernation: Allocated 3123144 kbytes in 0.45 seconds (6940.32 MB/s)
[   50.126366] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[   50.127910] printk: Suspending console(s) (use no_console_suspend to debug)
[   50.128017] wlp4s0: deauthenticating from [MAC] by local choice (Reason: 3=DEAUTH_LEAVING)
[   50.625960] ACPI: EC: interrupt blocked
[   50.641836] ACPI: Preparing to enter system sleep state S4
[   50.646992] ACPI: EC: event blocked
[   50.646992] ACPI: EC: EC stopped
[   50.646993] PM: Saving platform NVS memory
[   50.647580] Disabling non-boot CPUs ...
[   50.648847] smpboot: CPU 1 is now offline
[   50.652131] smpboot: CPU 2 is now offline
[   50.654798] smpboot: CPU 3 is now offline
[   50.657551] PM: hibernation: Creating image:
[   50.856056] PM: hibernation: Need to copy 776500 pages
[   50.856058] PM: hibernation: Normal pages needed: 776500 + 1024, available pages: 3355079
[   51.339687] PM: hibernation: free pages cleared after restore
[   51.339731] PM: Restoring platform NVS memory
[   51.339933] ACPI: EC: EC started
[   51.340572] Enabling non-boot CPUs ...
[   51.340606] x86: Booting SMP configuration:
[   51.340607] smpboot: Booting Node 0 Processor 1 APIC 0x2
[   51.341177] CPU1 is up
[   51.341196] smpboot: Booting Node 0 Processor 2 APIC 0x1
[   51.341826] CPU2 is up
[   51.341848] smpboot: Booting Node 0 Processor 3 APIC 0x3
[   51.342433] CPU3 is up
[   51.343774] ACPI: Waking up from system sleep state S4
[   51.370255] ACPI: EC: interrupt unblocked
[   51.468446] usb usb1: root hub lost power or was reset
[   51.468447] usb usb2: root hub lost power or was reset
[   51.468454] ACPI: EC: event unblocked
[   51.470796] iwlwifi 0000:04:00.0: RF_KILL bit toggled to enable radio.
[   51.489442] iwlwifi 0000:04:00.0: Applying debug destination EXTERNAL_DRAM
[   51.623015] iwlwifi 0000:04:00.0: Applying debug destination EXTERNAL_DRAM
[   51.690023] nvme nvme0: Shutdown timeout set to 8 seconds
[   51.690845] iwlwifi 0000:04:00.0: FW already configured (0) - re-configuring
[   51.709373] nvme nvme0: 4/0/0 default/read/poll queues
[   51.826066] usb 1-1: reset full-speed USB device number 2 using xhci_hcd
[   52.089298] usb 1-2: reset full-speed USB device number 3 using xhci_hcd
[   52.352621] usb 1-7: reset full-speed USB device number 4 using xhci_hcd
[   52.616012] usb 1-9: reset full-speed USB device number 5 using xhci_hcd
[   52.758946] acpi LNXPOWER:02: Turning OFF
[   52.759116] acpi LNXPOWER:01: Turning OFF
[   52.759368] mei_hdcp 0000:00:16.0-b638ab7e-94e2-4ea2-a552-d1c54b627f04: bound 0000:00:02.0 (ops i915_hdcp_component_ops [i915])
[   52.760085] PM: hibernation: Basic memory bitmaps freed
[   52.760094] OOM killer enabled.
[   52.760095] Restarting tasks ... 
[   52.761890] Bluetooth: hci0: Bootloader revision 0.0 build 26 week 38 2015
[   52.764974] Bluetooth: hci0: Device revision is 16
[   52.764978] Bluetooth: hci0: Secure boot is enabled
[   52.764982] Bluetooth: hci0: OTP lock is enabled
[   52.764984] Bluetooth: hci0: API lock is enabled
[   52.764987] Bluetooth: hci0: Debug lock is disabled
[   52.764991] Bluetooth: hci0: Minimum firmware build 1 week 10 2014
[   52.765469] done.
[   52.773608] Bluetooth: hci0: Found device firmware: intel/ibt-12-16.sfi
[   52.795886] PM: hibernation: hibernation exit

IIRC it never worked on 5.7. So, is this a regression?
Interestingly it works on 5.8rc5.d0712.g11ba468-1 again.

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