Okay, so I'm trying to figure out whether this QEMU bug is related to user-mode or system-mode. Let me start by understanding the problem description. The user reports that since QEMU 8.1.5, their aarch64 emulation has become much slower. They're using a Linux 5.4 kernel cross-compiled with the ARM toolchain. The noticeable issues are longer boot times and significantly slower memory accesses—specifically, about three times as slow when running a script that accesses memory addresses repeatedly. They mention that the problem started in version 8.1.5 and is also present in 8.2.1. However, when they tested it on the master branch (which I assume is more recent or development code), the issue wasn't there. They've traced the problem to a specific commit on the 8.2 branch related to TCG (Translation Cache Generator) acceleration and how translation blocks are mapped. Now, considering whether this is a user-mode or system-mode issue. User-mode typically deals with applications running in user space without requiring high privileges, while system-mode involves higher-privilege operations like emulating hardware devices, handling peripherals, or dealing with the operating system's kernel-level functions. In this case, the problem affects the boot time of a Linux kernel and memory access speeds within the virtual machine. Both of these are low-level operations that would be handled in system-mode because they involve initializing the OS, managing hardware emulation, and system resources. The fact that it's related to TCG acceleration suggests it's about how QEMU translates and executes code at a lower level, which is part of system-mode. The user also provided specific commits affecting the translation blocks, which relates to how the CPU is emulated in QEMU. This would be part of the virtualization process, specifically for system emulation rather than user space applications. Therefore, this issue seems to be related to system-mode because it involves the kernel and low-level hardware emulation performance. system