Debugging ACPI Events in the kernel using QEMU

Kernel Build

Build the kernel with ACPI debug enabled as described in https://www.kernel.org/doc/Documentation/acpi/debug.txt

tl;dr

ACPI debug output is globally enabled by CONFIG_ACPI_DEBUG.  If this config option is turned off, the debug messages are not even built into the
kernel.
When CONFIG_ACPI_DEBUG=y, you can select the component and level of messages you're interested in.  At boot-time, use the acpi.debug_layer and acpi.debug_level kernel command line options.  After boot, you can use the debug_layer and debug_level files in /sys/module/acpi/parameters/ to control the debug messages.
The "debug_layer" is a mask that selects components of interest, e.g., a specific driver or part of the ACPI interpreter.  To build the debug_layer bitmask, look for the "#define _COMPONENT" in an ACPI source file.
The "debug_level" is a mask that selects different types of messages, e.g., those related to initialization, method execution, informational messages, etc. To build debug_level, look at the level specified in an ACPI_DEBUG_PRINT() statement.
The ACPI interpreter uses several different levels, but the Linux
ACPI core and ACPI drivers generally only use ACPI_LV_INFO.

Launching QEMU

#!/bin/bash
# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
# ex: ts=8 sw=4 sts=4 et filetype=sh
VMN=${VMN:=1}
QEMU=qemu-system-x86_64
let APCI_UTILITIES=0x00000001
let APCI_HARDWARE=0x00000002
let APCI_EVENTS=0x00000004
let APCI_TABLES=0x00000008
let APCI_NAMESPACE=0x00000010
let APCI_PARSER=0x00000020
let APCI_DISPATCHER=0x00000040
let APCI_EXECUTER=0x00000080
let APCI_RESOURCES=0x00000100
let APCI_CA_DEBUGGER=0x00000200
let APCI_OS_SERVICES=0x00000400
let APCI_CA_DISASSEMBLER=0x00000800
let APCI_COMPILER=0x00001000
let APCI_TOOLS=0x00002000
let APCI_BUS_COMPONENT=0x00010000
let APCI_AC_COMPONENT=0x00020000
let APCI_BATTERY_COMPONENT=0x00040000
let APCI_BUTTON_COMPONENT=0x00080000
let APCI_SBS_COMPONENT=0x00100000
let APCI_FAN_COMPONENT=0x00200000
let APCI_PCI_COMPONENT=0x00400000
let APCI_POWER_COMPONENT=0x00800000
let APCI_CONTAINER_COMPONENT=0x01000000
let APCI_SYSTEM_COMPONENT=0x02000000
let APCI_THERMAL_COMPONENT=0x04000000
let APCI_MEMORY_DEVICE_COMPONENT=0x08000000
let APCI_VIDEO_COMPONENT=0x10000000
let APCI_PROCESSOR_COMPONENT=0x20000000
let acpi_debug_layer=$((APCI_HARDWARE|APCI_EVENTS|APCI_PCI_COMPONENT|APCI_TABLES|APCI_RESOURCES|APCI_BUS_COMPONENT|APCI_BUTTON_COMPONENT|APCI_OS_SERVICES|APCI_PROCESSOR_COMPONENT|APCI_MEMORY_DEVICE_COMPONENT|APCI_RESOURCES))
let APCI_LV_INIT=0x00000001
let APCI_LV_DEBUG_OBJECT=0x00000002
let APCI_LV_INFO=0x00000004
let APCI_LV_INIT_NAMES=0x00000020
let APCI_LV_PARSE=0x00000040
let APCI_LV_LOAD=0x00000080
let APCI_LV_DISPATCH=0x00000100
let APCI_LV_EXEC=0x00000200
let APCI_LV_NAMES=0x00000400
let APCI_LV_OPREGION=0x00000800
let APCI_LV_BFIELD=0x00001000
let APCI_LV_TABLES=0x00002000
let APCI_LV_VALUES=0x00004000
let APCI_LV_OBJECTS=0x00008000
let APCI_LV_RESOURCES=0x00010000
let APCI_LV_USER_REQUESTS=0x00020000
let APCI_LV_PACKAGE=0x00040000
let APCI_LV_ALLOCATIONS=0x00100000
let APCI_LV_FUNCTIONS=0x00200000
let APCI_LV_OPTIMIZATIONS=0x00400000
let APCI_LV_MUTEX=0x01000000
let APCI_LV_THREADS=0x02000000
let APCI_LV_IO=0x04000000
let APCI_LV_INTERRUPTS=0x08000000
let APCI_LV_AML_DISASSEMBLE=0x10000000
let APCI_LV_VERBOSE_INFO=0x20000000
let APCI_LV_FULL_TABLES=0x40000000
let APCI_LV_EVENTS=0x80000000
let apci_debug_level=$((APCI_LV_INFO|APCI_LV_DEBUG_OBJECT|APCI_LV_INTERRUPTS|APCI_LV_EVENTS|APCI_LV_IO|APCI_LV_FUNCTIONS|APCI_LV_DISPATCH|APCI_LV_OPREGION|APCI_LV_FULL_TABLES|APCI_LV_VERBOSE_INFO))
sudo $QEMU \
     -bios OVMF.fd \
     -enable-kvm \
     -nodefaults \
     -vga none -nographic \
     -smp sockets=1,cpus=4,cores=2,maxcpus=8 -cpu host \
     -m 512 \
     -kernel bzImage -append 'console=hvc0 iommu=false root=/dev/vda3 rw rootfstype=ext4 data=ordered rcupdate.rcu_expedited=1 tsc=reliable no_timer_check reboot=t noapictimer acpi.debug_layer='"${acpi_debug_layer}"' acpi.debug_level='"${apci_debug_level}"' log_buf_len=1M loglevel=2' \
     -device virtio-blk-pci,drive=image -drive if=none,id=image,file=clear.img,format=raw \
     -device virtio-serial-pci,id=virtio-serial0 -device virtconsole,chardev=charconsole0,id=console0 -chardev stdio,id=charconsole0 \
     -monitor telnet:127.0.0.1:55555,server,nowait \