1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
|
<think>
Okay, so I'm trying to figure out whether this QEMU crash on a Pandaboard is a user-mode or system-mode issue. Let me break it down.
First, the user provided the output from uname -a which shows the kernel version and architecture. It's running on an ARMv7l system with Linux omap 3.1.6-x. Then, when they run qemu, it crashes with an error about KVM initialization and a fatal TCG error in tcg-target.c.
QEMU can run in two modes: user-mode and system-mode. User-mode QEMU emulates a CPU for running binaries of different architectures without booting an entire OS, while system-mode simulates the entire hardware environment, including peripherals and devices, which is used to boot guest operating systems.
In this case, when they ran 'qemu' without any arguments, it probably defaulted to user-mode. But the error mentions KVM initialization failure. KVM is a kernel module that allows QEMU to use hardware virtualization for better performance in system-mode. However, since the Pandaboard's kernel might not have KVM support or the necessary modules loaded, QEMU falls back to software TCG (Translation-Cache-Based Engine) which handles CPU emulation.
The fatal error occurs in tcg-target.c at line 848. The fact that it's a TCG issue suggests it's trying to emulate the ARM architecture. If this were system-mode, there might be more context about devices or the OS booting, but since they just ran 'qemu' without specifying an OS image or other parameters, it's likely in user-mode where it's trying to run some code.
So putting it all together, the crash is happening because QEMU is trying to emulate a CPU (user-mode) and encountered a fatal error during that process. Therefore, this bug report is related to user-mode.
</think>
The issue occurs when QEMU tries to emulate a CPU in user-mode without proper KVM support, leading to a TCG fatal error.
**Answer:** user
|