联想ThinkPad P15s Gen 2i（Ubuntu 22.04.2 LTS）风扇停转及CPU频率异常问题求助

我最近在用联想P15s Gen 2i笔记本时碰到了棘手的问题：先是发现后盖塑料有类似“熔化”的迹象，更诡异的是完全听不到风扇的运转声！

出于好奇，我安装了sensors工具检测硬件状态，结果如下：

首先查看工具版本：

$ sensors --version
sensors version 3.6.0 with libsensors version 3.6.0

传感器完整输出：

$ sensors
iwlwifi_1-virtual-0
Adapter: Virtual device
temp1:        +67.0°C

nouveau-pci-0100
Adapter: PCI adapter
temp1:            N/A  (high = +95.0°C, hyst =  +3.0°C)
(crit = +105.0°C, hyst =  +5.0°C)
(emerg = +135.0°C, hyst =  +5.0°C)

BAT0-acpi-0
Adapter: ACPI interface
in0:          12.88 V

thinkpad-isa-0000
Adapter: ISA adapter
fan1:           0 RPM
CPU:          +77.0°C
GPU:              N/A
temp3:        +76.0°C
temp4:         +0.0°C
temp5:        +77.0°C
temp6:        +77.0°C
temp7:        +78.0°C
temp8:            N/A

coretemp-isa-0000
Adapter: ISA adapter
Package id 0:  +76.0°C  (high = +100.0°C, crit = +100.0°C)
Core 0:        +77.0°C  (high = +100.0°C, crit = +100.0°C)
Core 1:        +79.0°C  (high = +100.0°C, crit = +100.0°C)
Core 2:        +82.0°C  (high = +100.0°C, crit = +100.0°C)
Core 3:        +81.0°C  (high = +100.0°C, crit = +100.0°C)

nvme-pci-0400
Adapter: PCI adapter
Composite:    +69.9°C  (low  = -273.1°C, high = +83.8°C)
(crit = +84.8°C)
Sensor 1:     +69.9°C  (low  = -273.1°C, high = +65261.8°C)
Sensor 2:     +69.9°C  (low  = -273.1°C, high = +65261.8°C)

acpitz-acpi-0
Adapter: ACPI interface
temp1:        +72.0°C  (crit = +128.0°C)
+72.0°C  (crit = +128.0°C)

之后我又安装了lm-sensors并运行sensor-detect，按照提示将coretemp添加到了/etc/modules文件中：

~$ cat /etc/modules
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
# Generated by sensors-detect on Thu Mar 16 23:46:51 2023
# Chip drivers
coretemp

接着执行了模块启动命令并确认lm-sensors版本：

$ /etc/init.d/kmod start
$ apt-cache policy lm-sensors
lm-sensors:
Installed: 1:3.6.0-7ubuntu1
Candidate: 1:3.6.0-7ubuntu1
Version table:
*** 1:3.6.0-7ubuntu1 500
500 http://ch.archive.ubuntu.com/ubuntu jammy/universe amd64 Packages
100 /var/lib/dpkg/status

但重启后问题完全没有改善——就算在高负载状态下，风扇依然保持0转速。

另外我还发现CPU频率存在异常：我的CPU是11代Intel i7-1165G7，lscpu显示最高能跑到4.7GHz，但用stress --cpu 8跑满负载时，频率却卡在了3.96GHz左右：

正常使用时的CPU频率：

$ grep MHz /proc/cpuinfo
cpu MHz     : 1137.014
cpu MHz     : 922.759
cpu MHz     : 1127.838
cpu MHz     : 1255.019
cpu MHz     : 1159.533
cpu MHz     : 521.957
cpu MHz     : 1246.749
cpu MHz     : 1263.212

高负载下的CPU频率：

$ grep MHz /proc/cpuinfo
cpu MHz     : 3959.109
cpu MHz     : 3959.044
cpu MHz     : 3959.019
cpu MHz     : 3959.131
cpu MHz     : 3959.134
cpu MHz     : 3959.043
cpu MHz     : 3958.995
cpu MHz     : 3959.111

我还检查了热守护进程的状态，发现它无法正常运行：

$ sudo systemctl status thermald.service
○ thermald.service - Thermal Daemon Service
Loaded: loaded (/lib/systemd/system/thermald.service; enabled; vendor preset: enabled)
Active: inactive (dead) since Fri 2023-03-17 00:18:17 CET; 13h ago
Main PID: 1082 (code=exited, status=0/SUCCESS)
CPU: 6ms

mar 17 00:18:17 laptop-ThinkPad systemd[1]: Starting Thermal Daemon Service...
mar 17 00:18:17 laptop-ThinkPad thermald[1082]: 27 CPUID levels; family:model:stepping 0x6:8c:1 (6:140:1)
mar 17 00:18:17 laptop-ThinkPad thermald[1082]: [/sys/devices/platform/thinkpad_acpi/dytc_lapmode] present: Thermald can't run on this platform
mar 17 00:18:17 laptop-ThinkPad thermald[1082]: Unsupported cpu model or platform
mar 17 00:18:17 laptop-ThinkPad systemd[1]: thermald.service: Deactivated successfully.
mar 17 00:18:17 laptop-ThinkPad systemd[1]: Started Thermal Daemon Service.

我的系统完整信息：

• OS: Ubuntu 22.04.2 LTS x86_64
• Host: 20W6004XMZ ThinkPad P15s Gen 2i
• Kernel: 5.19.0-35-generic
• CPU: 11th Gen Intel i7-1165G7 (8) @ 4.700GHz
• GPU: NVIDIA Quadro T500 Mobile / Intel TigerLake-LP GT2 [Iris Xe Graphics]
• Memory: 4592MiB / 31824MiB

想请教大家：是什么原因导致风扇停转？我该怎么让它恢复正常？另外CPU频率卡在3.96GHz无法达到标称的4.7GHz，这和风扇问题有关联吗？

备注：内容来源于stack exchange，提问作者s.k