Comment 1 for bug 1804961

On Sat, 24 Nov 2018 20:36:54 -0000
GH Cao <email address hidden> wrote:

> ** Description changed:
>
> When I emulate a virt-3.0 machine, Windows 10 BSoD on boot, with the
> error code being ACPI_BIOS_ERROR(0x000000A5), virt-2.12 boots fine.
>
> Windows Build: 10.0.17134.1
> QEMU version: 3.0.0
> Commandline: qemu-system-aarch64 -M virt -accel tcg,thread=multi -cpu cortex-a57 -smp 2 -m 2048 -bios QEMU_EFI.fd -device ramfb -device nec-usb-xhci -device usb-kbd -device usb-tablet -hda disk.vhd -vnc :0
>
> By the way, the patch to add DBG2 table discussed here
> - https://lists.gnu.org/archive/html/qemu-devel/2015-09/msg02550.html
> + https://lists.gnu.org/archive/html/qemu-devel/2015-09/msg01719.html
> works (although minor change is required to adapt to the qemu 3.0.0
> code), the table is accepted by Windows (Windows require both DBG2 and
> SPCR to be valid for serial kernel debugging to work), so it may help
> further diagnosing this issue.
>

if you are able to attach a debugger early before guest BSODs,
you can try to use AMIL Debugger
https://docs.microsoft.com/en-us/windows-hardware/drivers/debugger/the-amli-debugger
to find out what windows doesn't like in ACPI tables.