This patch series introduces support for the Zhaoxin Yongfeng CPU model and
includes
some improvements and updates related to Zhaoxin and VIA CPUs. The changes
ensure that
QEMU can correctly identify and emulate Zhaoxin CPUs, providing accurate
functionality
and performance characteristics.
### Summary of Changes
EwanHai (4):
target/i386: Add support for Zhaoxin/VIA CPU vendor identification
target/i386: Add CPUID leaf 0xC000_0001 EDX definitions
target/i386: Introduce Zhaoxin Yongfeng CPU model
target/i386: Update CMPLegacy handling for Zhaoxin and VIA CPUs
target/i386/cpu.c | 130 ++++++++++++++++++++++++++++++++++++++++++++--
target/i386/cpu.h | 38 ++++++++++++++
2 files changed, 165 insertions(+), 3 deletions(-)
### Known Bugs
1. Issue with VMX Preemption Timer Rate on Yongfeng CPU:
- Description: On Yongfeng CPUs, the VMX preemption timer rate is 128,
meaning that
bits 4:0 of MSR_IA32_VMX_MISC_CTLS should be set to 7. However, due to
Intel's rate
being 5, the Linux kernel has hardcoded this value as 5:
`#define VMX_MISC_EMULATED_PREEMPTION_TIMER_RATE 5`
- Impact: This discrepancy can cause incorrect behavior in the VMX
preemption timer on
Yongfeng CPUs.
- Workaround: A patch to correct this issue in the Linux kernel is currently
being
prepared and will be submitted soon.
--
2.34.1
