在这个地址下载linux-5.15.119.tar.xz ：https://cdn.kernel.org/pub/linux/kernel/v5.x/
在这个地址下载patch-5.15.119-rt65.patch.xz：https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.15/older/
然后放入ubuntu的文件夹中，进行解压：
root@raojs-virtual-machine:/opt# tar -xf linux-5.15.119.tar.xz
root@raojs-virtual-machine:/opt# ls
linux-5.15.119 linux-5.15.119.tar.xz patch-5.15.119-rt65.patch.xz
root@raojs-virtual-machine:/opt# cd linux-5.15.119/
root@raojs-virtual-machine:/opt/linux-5.15.119# ls
arch certs CREDITS Documentation fs init ipc Kconfig lib MAINTAINERS mm README scripts sound usr
block COPYING crypto drivers include io_uring Kbuild kernel LICENSES Makefile net samples security tools virt
root@raojs-virtual-machine:/opt/linux-5.15.119# cd ..
root@raojs-virtual-machine:/opt# xz -d patch-5.15.119-rt65.patch.xz然后，打补丁：
cd linux-5.15.119
patch -p1 < ../patch-5.15.119-rt65.patch回答问题：
# 1. Timer tick handling - 选择 Full dynticks
choice[1-3?]: 3
# 2. Force context tracking - 选择 N（推荐）
Force context tracking (CONTEXT_TRACKING_FORCE) [N/y] (NEW): n
抢占模型选择（最关键）
# 当出现 Preemption Model 选项时
Preemption Model
1. No Forced Preemption (Server) (PREEMPT_NONE)
2. Voluntary Kernel Preemption (Desktop) (PREEMPT_VOLUNTARY)
3. Preemptible Kernel (Low-Latency Desktop) (PREEMPT)
> 4. Fully Preemptible Kernel (Real-Time) (PREEMPT_RT)
choice[1-4?]: 4
# CPU 隔离（如果需要专用核心运行实时任务）
CPU isolation (RCU_NOCB_CPU) [N/y] (NEW): y
# 追踪器选项（调试用，通常选 N）
Tracers (FTRACE) [Y/n] (NEW): n
# 高性能计时器
High Resolution Timer Support (HIGH_RES_TIMERS) [Y/n] (NEW): y
# 中断合并延迟
Interrupt merging (IRQ_MERGE) [N/y] (NEW): n
# RCU 回调卸载（推荐）
Offload RCU callback processing from boot-selected CPUs (RCU_NOCB_CPU) [N/y] (NEW): y
# CPU 频率调控（对实时性有影响）
CPU Frequency scaling (CPU_FREQ) [Y/n] (NEW): y
# 选择性能模式
Default CPUFreq governor (performance)
Milliseconds to delay boosting after RCU grace-period start (RCU_BOOST_DELAY) [500] (NEW)
默认值：回车
后面可多次回车
选择2即可：
Legacy applications
1.Full emulation (LEGACY_VSYSCALL_EMULATE) (NEW)
>2.Emulate execution only (LEGACY VSYSCALL XONLY)
3. None (LEGACY VSYSCALL NONE)
choice[1-3?]:
可选2或者3：
Which hash algorithm should modules be signed with?
1.Sign modules with SHA-1 (MODULE SIG SHA1)
2 Sign modules With SHA-224 (MODULE SIG SHA224) (NEW)
3 Sign modules with SHA-256 (MODULE SIG SHA256
4 Sign modules With SHA-384 (MODULE SIG SHA384)
5 Sign modules with SHA-512 (MODULE SIG SHA512)复制当前配置（关键）：cp /boot/config-$(uname -r) .config
然后：make oldconfig
打开实时选项（核心步骤）：make menuconfig
进入：
General Setup --->
Preemption Model --->选择：
( ) No Forced Preemption
( ) Voluntary Kernel Preemption
( ) Preemptible Kernel
(*) Fully Preemptible Kernel (Real-Time)编译内核（耗时）
make -j$(nproc)
make modules_install
sudo make install遇到问题1：无法更新软件包
root@raojs-virtual-machine:/opt/linux-5.15.119# sudo apt update 忽略:1 http://cn.archive.ubuntu.com/ubuntu jammy InRelease 忽略:2 http://security.ubuntu.com/ubuntu jammy-security InRelease 忽略:1 http://cn.archive.ubuntu.com/ubuntu jammy InRelease 忽略:2 http://security.ubuntu.com/ubuntu jammy-security InRelease 忽略:1 http://cn.archive.ubuntu.com/ubuntu jammy InRelease 忽略:2 http://security.ubuntu.com/ubuntu jammy-security InRelease 错误:1 http://cn.archive.ubuntu.com/ubuntu jammy InRelease 暂时不能解析域名"cn.archive.ubuntu.com" 错误:2 http://security.ubuntu.com/ubuntu jammy-security InRelease 暂时不能解析域名"security.ubuntu.com" 正在读取软件包列表... 完成 正在分析软件包的依赖关系树... 完成 正在读取状态信息... 完成 所有软件包均为最新。 W: 无法下载 http://cn.archive.ubuntu.com/ubuntu/dists/jammy/InRelease 暂时不能解析域名"cn.archive.ubuntu.com" W: 无法下载 http://security.ubuntu.com/ubuntu/dists/jammy-security/InRelease 暂时不能解析域名"security.ubuntu.com" W: 部分索引文件下载失败。如果忽略它们，那将转而使用旧的索引文件。 root@raojs-virtual-machine:/opt/linux-5.15.119# ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. From 192.168.0.100 icmp_seq=54 Destination Host Unreachable From 192.168.0.100 icmp_seq=55 Destination Host Unreachable解决方法：配置 VMware NAT 端口映射。编辑 → 虚拟网络编辑器→ VMnet8（NAT）→NAT Settings → Port Forwarding
这项需要配置正确，然后才可以正常使用MobaXterm这类软件连接ubuntu.
