It looks like (sadly) almost no one uses newer iMacs for Ubuntu or Linux generally. But I'm posting this question anyway, just in case someone out there is.
The problem is that on any Suspend other than the first of the session after startup, the iMac **reboots rather than suspends.**
I post below journalctl entries for three successive attempts to suspend: (1) after initial boot; (2) after resume from initial boot suspend; (3) after reboot from crash due to #2. Please let me know if anything else will help!
Here they are:
INITIAL BOOT THEN SUSPEND
Apr 04 16:16:16 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038576.4448] manager: sleep: sleep requested (sleeping: no enabled: yes)
Apr 04 16:16:16 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038576.4448] device (p2p-dev-wlp3s0): state change: disconnected -> unmanaged (reason 'sleeping', sys-iface-state: 'managed')
Apr 04 16:16:16 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038576.4451] manager: NetworkManager state is now ASLEEP
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: ../../../gobject/gsignal.c:2647: instance '0x5618fbbb2000' has no handler with id '110525'
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-north".
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-east".
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-south".
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-west".
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-left-screen".
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-right-screen".
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-cycle".
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: JS WARNING: [resource:///org/gnome/gjs/modules/signals.js 135]: Too many arguments to method Clutter.Actor.destroy: expected 0, got 1
Apr 04 16:16:16 Ubuntu-iMac2019 gnome-shell[1912]: JS WARNING: [resource:///org/gnome/gjs/modules/signals.js 135]: Too many arguments to method Clutter.Actor.destroy: expected 0, got 1
Apr 04 16:16:19 Ubuntu-iMac2019 systemd[1]: Reached target Sleep.
Apr 04 16:16:19 Ubuntu-iMac2019 systemd[1]: Starting Suspend...
Apr 04 16:16:19 Ubuntu-iMac2019 systemd-sleep[4642]: Suspending system...
Apr 04 16:16:19 Ubuntu-iMac2019 kernel: PM: suspend entry (deep)
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: Filesystems sync: 0.943 seconds
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: Freezing user space processes ... (elapsed 0.003 seconds) done.
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: OOM killer disabled.
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: printk: Suspending console(s) (use no_console_suspend to debug)
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: sd 0:0:0:0: [sda] Synchronizing SCSI cache
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: sd 0:0:0:0: [sda] Stopping disk
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: EC: interrupt blocked
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: Preparing to enter system sleep state S3
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: EC: event blocked
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: EC: EC stopped
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: PM: Saving platform NVS memory
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: Disabling non-boot CPUs ...
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 35: no longer affine to CPU1
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 60: no longer affine to CPU1
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 62: no longer affine to CPU1
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: smpboot: CPU 1 is now offline
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 16: no longer affine to CPU2
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 33: no longer affine to CPU2
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 56: no longer affine to CPU2
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 64: no longer affine to CPU2
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: smpboot: CPU 2 is now offline
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 54: no longer affine to CPU3
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 63: no longer affine to CPU3
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: IRQ 65: no longer affine to CPU3
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: smpboot: CPU 3 is now offline
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: Low-level resume complete
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: EC: EC started
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: PM: Restoring platform NVS memory
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: Enabling non-boot CPUs ...
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: x86: Booting SMP configuration:
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: smpboot: Booting Node 0 Processor 1 APIC 0x2
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: intel_pstate: Disabling energy efficiency optimization
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: CPU1 is up
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: smpboot: Booting Node 0 Processor 2 APIC 0x4
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: CPU2 is up
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: smpboot: Booting Node 0 Processor 3 APIC 0x6
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: CPU3 is up
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: Waking up from system sleep state S3
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: EC: interrupt unblocked
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ACPI: EC: event unblocked
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: sd 0:0:0:0: [sda] Starting disk
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: usb usb3: root hub lost power or was reset
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: usb usb4: root hub lost power or was reset
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: [drm] PCIE GART of 256M enabled (table at 0x000000F400000000).
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: [drm] UVD and UVD ENC initialized successfully.
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: [drm] VCE initialized successfully.
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: nvme nvme0: 1/0/0 default/read/poll queues
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: usb 1-5: reset high-speed USB device number 4 using xhci_hcd
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ata1: link is slow to respond, please be patient (ready=0)
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ata1.00: unexpected _GTF length (8)
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ata1.00: unexpected _GTF length (8)
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: ata1.00: configured for UDMA/133
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: thunderbolt 0000:07:00.0: failed to send driver ready to ICM
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: OOM killer enabled.
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: Restarting tasks ... done.
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: video LNXVIDEO:00: Restoring backlight state
Apr 04 16:20:33 Ubuntu-iMac2019 kernel: PM: suspend exit
Apr 04 16:20:33 Ubuntu-iMac2019 systemd-sleep[4642]: System resumed.
Apr 04 16:20:33 Ubuntu-iMac2019 rtkit-daemon[1257]: The canary thread is apparently starving. Taking action.
Apr 04 16:20:33 Ubuntu-iMac2019 NetworkManager[983]: <warn> [1586038833.6925] sup-iface[0x5563887bf8f0,wlp3s0]: connection disconnected (reason -3)
Apr 04 16:20:33 Ubuntu-iMac2019 rtkit-daemon[1257]: Demoting known real-time threads.
Apr 04 16:20:33 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038833.6937] device (wlp3s0): supplicant interface state: completed -> disconnected
Apr 04 16:20:33 Ubuntu-iMac2019 rtkit-daemon[1257]: Successfully demoted thread 1657 of process 1639.
Apr 04 16:20:33 Ubuntu-iMac2019 rtkit-daemon[1257]: Successfully demoted thread 1656 of process 1639.
Apr 04 16:20:33 Ubuntu-iMac2019 rtkit-daemon[1257]: Successfully demoted thread 1639 of process 1639.
Apr 04 16:20:33 Ubuntu-iMac2019 rtkit-daemon[1257]: Demoted 3 threads.
Apr 04 16:20:33 Ubuntu-iMac2019 wpa_supplicant[984]: wlp3s0: CTRL-EVENT-DISCONNECTED bssid=82:16:f9:63:3f:18 reason=3 locally_generated=1
Apr 04 16:20:33 Ubuntu-iMac2019 wpa_supplicant[984]: dbus: wpa_dbus_property_changed: no property SessionLength in object /fi/w1/wpa_supplicant1/Interfaces/0
Apr 04 16:20:33 Ubuntu-iMac2019 wpa_supplicant[984]: wlp3s0: CTRL-EVENT-REGDOM-CHANGE init=CORE type=WORLD
Apr 04 16:20:33 Ubuntu-iMac2019 /usr/lib/gdm3/gdm-x-session[1653]: (II) AMDGPU(0): EDID vendor "APP", prod id 44561
Apr 04 16:20:33 Ubuntu-iMac2019 /usr/lib/gdm3/gdm-x-session[1653]: (II) AMDGPU(0): Printing DDC gathered Modelines:
Apr 04 16:20:33 Ubuntu-iMac2019 /usr/lib/gdm3/gdm-x-session[1653]: (II) AMDGPU(0): Modeline "3840x2160"x0.0 533.25 3840 3888 3920 4000 2160 2163 2168 2222 +hsync -vsync (133.3 kHz eP)
Apr 04 16:20:33 Ubuntu-iMac2019 /usr/lib/gdm3/gdm-x-session[1653]: (II) AMDGPU(0): Modeline "2560x1440"x0.0 241.50 2560 2608 2640 2720 1440 1443 1448 1481 +hsync -vsync (88.8 kHz e)
Apr 04 16:20:33 Ubuntu-iMac2019 /usr/lib/gdm3/gdm-x-session[1653]: (II) AMDGPU(0): Modeline "3200x1800"x0.0 373.25 3200 3248 3280 3360 1800 1803 1808 1852 +hsync -vsync (111.1 kHz e)
Apr 04 16:20:33 Ubuntu-iMac2019 gnome-shell[1912]: An active wireless connection, in infrastructure mode, involves no access point?
Apr 04 16:20:33 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038833.8241] device (wlp3s0): supplicant interface state: disconnected -> scanning
Apr 04 16:20:33 Ubuntu-iMac2019 systemd-sleep[4642]: /dev/sda:
Apr 04 16:20:33 Ubuntu-iMac2019 systemd-sleep[4642]: setting Advanced Power Management level to 0xfe (254)
Apr 04 16:20:33 Ubuntu-iMac2019 systemd-sleep[4642]: APM_level = 254
Apr 04 16:20:33 Ubuntu-iMac2019 systemd[1]: systemd-suspend.service: Succeeded.
Apr 04 16:20:33 Ubuntu-iMac2019 systemd[1]: Started Suspend.
Apr 04 16:20:33 Ubuntu-iMac2019 systemd[1]: Stopped target Sleep.
Apr 04 16:20:33 Ubuntu-iMac2019 systemd[1]: Reached target Suspend.
Apr 04 16:20:33 Ubuntu-iMac2019 systemd[1]: Stopped target Suspend.
Apr 04 16:20:33 Ubuntu-iMac2019 systemd-logind[969]: Operation 'sleep' finished.
Apr 04 16:20:33 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038833.9782] manager: sleep: wake requested (sleeping: yes enabled: yes)
Apr 04 16:20:33 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038833.9784] device (enp4s0f0): state change: unavailable -> unmanaged (reason 'sleeping', sys-iface-state: 'managed')
AFTER INITIAL SUSPEND, TRY AGAIN
Apr 04 16:23:01 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038981.5840] manager: sleep: sleep requested (sleeping: no enabled: yes)
Apr 04 16:23:01 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038981.5842] device (p2p-dev-wlp3s0): state change: disconnected -> unmanaged (reason 'sleeping', sys-iface-state: 'managed')
Apr 04 16:23:01 Ubuntu-iMac2019 NetworkManager[983]: <info> [1586038981.5851] manager: NetworkManager state is now ASLEEP
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: ../../../gobject/gsignal.c:2647: instance '0x5618fbbb2000' has no handler with id '155647'
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-north".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-east".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-south".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-west".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-left-screen".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-right-screen".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-cycle".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-north".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-east".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-south".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-west".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-left-screen".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-right-screen".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: Window manager warning: Trying to remove non-existent keybinding "move-focus-cycle".
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: JS WARNING: [resource:///org/gnome/gjs/modules/signals.js 135]: Too many arguments to method Clutter.Actor.destroy: expected 0, got 1
Apr 04 16:23:01 Ubuntu-iMac2019 gnome-shell[1912]: JS WARNING: [resource:///org/gnome/gjs/modules/signals.js 135]: Too many arguments to method Clutter.Actor.destroy: expected 0, got 1
Apr 04 16:23:05 Ubuntu-iMac2019 systemd[1]: Reached target Sleep.
Apr 04 16:23:05 Ubuntu-iMac2019 systemd[1]: Starting Suspend...
-- Reboot --
Apr 04 16:37:09 Ubuntu-iMac2019 kernel: Linux version 5.3.0-45-generic (buildd@lgw01-amd64-008) (gcc version 9.2.1 20191008 (Ubuntu 9.2.1-9ubuntu2)) #37-Ubuntu SMP Thu Mar 26 20:41:27 UTC 2020 (Ubuntu 5.3.0-45.37-generic 5.3.18)
ANOTHER SUSPEND (SUCCESSFUL) AFTER FORCED REBOOT FROM PRIOR SUSPEND ATTEMPT
Apr 04 16:42:00 Ubuntu-iMac2019 NetworkManager[1014]: <info> [1586040120.1551] manager: sleep: sleep requested (sleeping: no enabled: yes)
Apr 04 16:42:00 Ubuntu-iMac2019 NetworkManager[1014]: <info> [1586040120.1552] device (p2p-dev-wlp3s0): state change: disconnected -> unmanaged (reason 'sleeping', sys-iface-state: 'managed')
Apr 04 16:42:00 Ubuntu-iMac2019 NetworkManager[1014]: <info> [1586040120.1554] manager: NetworkManager state is now ASLEEP
Apr 04 16:42:00 Ubuntu-iMac2019 gnome-shell[1880]: JS WARNING: [resource:///org/gnome/gjs/modules/signals.js 135]: Too many arguments to method Clutter.Actor.destroy: expected 0, got 1
Apr 04 16:42:00 Ubuntu-iMac2019 gnome-shell[1880]: JS WARNING: [resource:///org/gnome/gjs/modules/signals.js 135]: Too many arguments to method Clutter.Actor.destroy: expected 0, got 1
Apr 04 16:42:00 Ubuntu-iMac2019 gnome-shell[1880]: ../../../gobject/gsignal.c:2647: instance '0x5629baf1c030' has no handler with id '12369'
Apr 04 16:42:02 Ubuntu-iMac2019 systemd[1]: Reached target Sleep.
Apr 04 16:42:02 Ubuntu-iMac2019 systemd[1]: Starting Suspend...
Apr 04 16:42:02 Ubuntu-iMac2019 systemd-sleep[3608]: Suspending system...
Apr 04 16:42:02 Ubuntu-iMac2019 kernel: PM: suspend entry (deep)
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: Filesystems sync: 0.462 seconds
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: Freezing user space processes ... (elapsed 0.003 seconds) done.
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: OOM killer disabled.
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: printk: Suspending console(s) (use no_console_suspend to debug)
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: sd 0:0:0:0: [sda] Synchronizing SCSI cache
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: sd 0:0:0:0: [sda] Stopping disk
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: EC: interrupt blocked
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: Preparing to enter system sleep state S3
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: EC: event blocked
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: EC: EC stopped
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: PM: Saving platform NVS memory
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: Disabling non-boot CPUs ...
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 35: no longer affine to CPU1
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 36: no longer affine to CPU1
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 62: no longer affine to CPU1
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: smpboot: CPU 1 is now offline
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 16: no longer affine to CPU2
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 33: no longer affine to CPU2
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 56: no longer affine to CPU2
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 64: no longer affine to CPU2
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: smpboot: CPU 2 is now offline
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 38: no longer affine to CPU3
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 60: no longer affine to CPU3
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: IRQ 63: no longer affine to CPU3
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: smpboot: CPU 3 is now offline
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: Low-level resume complete
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: EC: EC started
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: PM: Restoring platform NVS memory
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: Enabling non-boot CPUs ...
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: x86: Booting SMP configuration:
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: smpboot: Booting Node 0 Processor 1 APIC 0x2
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: intel_pstate: Disabling energy efficiency optimization
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: CPU1 is up
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: smpboot: Booting Node 0 Processor 2 APIC 0x4
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: CPU2 is up
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: smpboot: Booting Node 0 Processor 3 APIC 0x6
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: CPU3 is up
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: Waking up from system sleep state S3
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: EC: interrupt unblocked
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ACPI: EC: event unblocked
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: sd 0:0:0:0: [sda] Starting disk
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: usb usb3: root hub lost power or was reset
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: usb usb4: root hub lost power or was reset
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: [drm] PCIE GART of 256M enabled (table at 0x000000F400000000).
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: [drm] UVD and UVD ENC initialized successfully.
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: [drm] VCE initialized successfully.
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: usb 1-5: reset high-speed USB device number 4 using xhci_hcd
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: nvme nvme0: 1/0/0 default/read/poll queues
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ata1: link is slow to respond, please be patient (ready=0)
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ata1.00: unexpected _GTF length (8)
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ata1.00: unexpected _GTF length (8)
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: ata1.00: configured for UDMA/133
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: thunderbolt 0000:07:00.0: failed to send driver ready to ICM
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: OOM killer enabled.
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: Restarting tasks ... done.
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: video LNXVIDEO:00: Restoring backlight state
Apr 04 16:57:44 Ubuntu-iMac2019 kernel: PM: suspend exit
Apr 04 16:57:44 Ubuntu-iMac2019 rtkit-daemon[1227]: The canary thread is apparently starving. Taking action.
Apr 04 16:57:44 Ubuntu-iMac2019 systemd-sleep[3608]: System resumed.
Apr 04 16:57:44 Ubuntu-iMac2019 rtkit-daemon[1227]: Demoting known real-time threads.
Apr 04 16:57:44 Ubuntu-iMac2019 rtkit-daemon[1227]: Successfully demoted thread 1641 of process 1605.
Apr 04 16:57:44 Ubuntu-iMac2019 rtkit-daemon[1227]: Successfully demoted thread 1638 of process 1605.
Apr 04 16:57:44 Ubuntu-iMac2019 rtkit-daemon[1227]: Successfully demoted thread 1605 of process 1605.
Apr 04 16:57:44 Ubuntu-iMac2019 rtkit-daemon[1227]: Demoted 3 threads.
Apr 04 16:57:44 Ubuntu-iMac2019 wpa_supplicant[1015]: wlp3s0: CTRL-EVENT-DISCONNECTED bssid=82:16:f9:63:3f:18 reason=3 locally_generated=1
Apr 04 16:57:44 Ubuntu-iMac2019 wpa_supplicant[1015]: dbus: wpa_dbus_property_changed: no property SessionLength in object /fi/w1/wpa_supplicant1/Interfaces/0
Apr 04 16:57:44 Ubuntu-iMac2019 wpa_supplicant[1015]: wlp3s0: CTRL-EVENT-REGDOM-CHANGE init=CORE type=WORLD
Apr 04 16:57:44 Ubuntu-iMac2019 /usr/lib/gdm3/gdm-x-session[1615]: (II) AMDGPU(0): EDID vendor "APP", prod id 44561
Apr 04 16:57:44 Ubuntu-iMac2019 systemd[1]: Starting Fingerprint Authentication Daemon...
Apr 04 16:57:45 Ubuntu-iMac2019 systemd-sleep[3608]: /dev/sda:
Apr 04 16:57:45 Ubuntu-iMac2019 systemd-sleep[3608]: setting Advanced Power Management level to 0xfe (254)
Apr 04 16:57:45 Ubuntu-iMac2019 systemd-sleep[3608]: APM_level = 254
Apr 04 16:57:44 Ubuntu-iMac2019 dbus-daemon[1013]: [system] Activating via systemd: service name='net.reactivated.Fprint' unit='fprintd.service' requested by ':1.345' (uid=1000 pid=1880 comm="/usr/bin/gnome-shell " label="unconfined")
DISTRIB_ID=Ubuntu DISTRIB_RELEASE=19.10 DISTRIB_CODENAME=eoan DISTRIB_DESCRIPTION="Ubuntu 19.10" NAME="Ubuntu" VERSION="19.10 (Eoan Ermine)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 19.10" VERSION_ID="19.10" HOME_URL="https://www.ubuntu.com/" VERSION_CODENAME=eoan UBUNTU_CODENAME=eoaninxiCPU: Quad Core Intel Core i5-7500 (-MCP-) speed/min/max: 800/800/3800 MHz Kernel: 5.3.0-45-generic x86_64 Up: 16h 34m Mem: 1821.4/7859.5 MiB (23.2%) Storage: 957.59 GiB (1.1% used) Procs: 263 Shell: bash 5.0.3 inxi: 3.0.36journalctl.....Apr 05 12:45:40 gsd-power[1135]: Error setting property 'PowerSaveMode' on interface org.gnome.Mutter.DisplayConfig: Timeout was reached (g-io-error-quark, 24)