Created attachment 200741 [details]
On a ThinkPad T420, either with CSM or UEFI boot, gives:
pci0: failed to set ACPI power state D3 on \134_SB_.PCI0.VID_: AE_BAD_PARAMETER
pcib0: failed to set ACPI power state D2 on \134_SB_.PCI0: AE_BAD_PARAMETER
acpi0: cleared fixed power button status
Then, either after the screen goes blank, or on resume, some things on the PCI bus end up broken. For me, it's the ehci controller and ethernet (em) controller.
ehci_interrupt: unrecoverable error, controller halted
frindex=0xffffffff ctrdsegm=0xffffffff periodic=0xffffffff async=0xffffffff
port 1 status=0xffffffff
port 2 status=0xffffffff
port 3 status=0xffffffff
ehci_interrupt: blocking interrupts 0x10
em does not give any dmesg output, continues to show up in ifconfig, but does not seem to work.
Suspend/resume worked on this machine in 11.2-RELEASE. I suspect something broke with the ACPI upgrade, but will keep investigating.
Created attachment 200743 [details]
Also affects Thinkpad X220.
Can you try 12.0-STABLE or CURRENT ?