Alright, so I'm trying to figure out whether this QEMU bug is user-mode or system-mode related. Let me go through the details step by step. The user is encountering an error when booting a Ubuntu-based OS image in QEMU. The error message mentions "Unhandled exception when booting UEFI x86_64 system image." They provided some output from both newer and older versions of QEMU, showing different errors but both pointing to issues during the kernel start. Looking at the GRUB settings, they're using a specific kernel and initrd. The error in the new QEMU is an assertion failure in the exception helper code, which suggests that something unexpected happened during execution. In the older QEMU, it's a General Protection fault with a lot of register details, pointing to a problem in the DxeCore.dll module. I know that QEMU emulates hardware and runs the guest OS in system mode, handling low-level operations like interrupts and exceptions. The fact that the error occurs during kernel boot suggests it's related to how QEMU is emulating the system-level components, possibly UEFI or the CPU context. The involvement of UEFI (as seen in the DxeCore.dll) indicates this is a firmware issue, which is part of the system setup and runs at a lower level than user applications. The exception handling and general protection fault are also signs that it's dealing with low-level operations, not application-specific issues. So, putting it all together, this bug seems to be related to how QEMU handles system-level components during boot, which makes it a system-mode issue. system