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x86: 0.998
architecture: 0.974
assembly: 0.897
device: 0.854
i386: 0.835
graphic: 0.701
vnc: 0.674
socket: 0.609
kernel: 0.586
ppc: 0.577
performance: 0.549
debug: 0.535
peripherals: 0.533
permissions: 0.525
risc-v: 0.525
network: 0.505
boot: 0.489
semantic: 0.444
arm: 0.434
register: 0.394
PID: 0.269
files: 0.263
KVM: 0.243
VMM: 0.227
hypervisor: 0.207
TCG: 0.194
mistranslation: 0.191
virtual: 0.155
user-level: 0.143
--------------------
x86: 1.000
i386: 0.973
assembly: 0.954
debug: 0.615
semantic: 0.359
register: 0.334
performance: 0.090
TCG: 0.078
architecture: 0.053
kernel: 0.052
virtual: 0.045
files: 0.044
user-level: 0.020
hypervisor: 0.014
device: 0.011
PID: 0.010
boot: 0.009
peripherals: 0.008
network: 0.008
risc-v: 0.004
permissions: 0.003
graphic: 0.002
socket: 0.002
ppc: 0.001
VMM: 0.001
vnc: 0.001
mistranslation: 0.000
KVM: 0.000
arm: 0.000
x86 LSL and LAR fault
Description of problem:
From the description of LSL and LAR instructions in manual, `If the segment descriptor cannot be accessed or is an invalid type for the instruction, the ZF flag is cleared and no value is loaded in the destination operand.`. When it happens at the CPU, it seems they do nothing (nop). However, in QEMU, it crashes.
Steps to reproduce:
1. Compile this code
```
void main() {
asm("mov rax, 0xa02e698e741f5a6a");
asm("mov rbx, 0x20959ddd7a0aef");
asm("lsl ax, bx");
}
```
2. Execute. QEMU crashes but CPU does not. This problem happens with LAR, too.
Additional information:
This bug is discovered by research conducted by KAIST SoftSec.
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