golang reflect无法识别地图成员的标记

我想用reflect提取struct的map members标签，但我发现如果从MapIndex中检索成员的值，它的类型将被识别为“*接口{}”，因此所有类型信息都会丢失，reflect无法提取详细信息。

package main

import (
    "fmt"
    "reflect"
)

type Student struct {
    Sname string `MyTag:"student-name"`
}

type Teacher struct {
    Name     string             `MyTag:"teacher-name"`
    Students map[string]Student `MyTag:"teacher-students"`
}

var sam = Teacher{
    Name: "Sam",
    Students: map[string]Student{
        "Sen": {
            Sname: "Sen",
        },
    },
}

func traversalTag(obj interface{}) {
    theType := reflect.TypeOf(obj)
    fmt.Printf("Traversal tag with obj: type %v, value %v\n", theType.String(), obj)

    elem := reflect.TypeOf(obj).Elem()
    for i := 0; i < elem.NumField(); i++ {
        fmt.Printf("Tag name %s, value %s\n", elem.Field(i).Name, elem.Field(i).Tag)
    }
}

func tryMapWithType(students map[string]Student) {
    for key, theValue := range students {
        fmt.Printf("Key: %v, Value: %v, value pointer %p\n", key, theValue, &theValue)
        traversalTag(&theValue)
    }
}

func tryMapWithReflect(obj interface{}) {
    reflectMap := reflect.ValueOf(obj)
    for _, key := range reflectMap.MapKeys() {
        theValue := reflectMap.MapIndex(key).Interface()
        fmt.Printf("Key: %v, Value: %v, value pointer %p\n", key, theValue, &theValue)
        traversalTag(&theValue) // Will have error
    }
}

func main() {
    tryMapWithType(sam.Students)
    tryMapWithReflect(sam.Students)
}

运行后，我出现以下错误：

Starting: C:\Users\Mento\go\bin\dlv.exe dap --check-go-version=false --listen=127.0.0.1:50308 from d:\Coding\Golang\demo
DAP server listening at: 127.0.0.1:50308
Key: Sen, Value: {Sen}, value pointer 0xc000044230
Traversal tag with obj: type *main.Student, value &{Sen}
Tag name Sname, value MyTag:"student-name"
Key: Sen, Value: {Sen}, value pointer 0xc0000442c0
Traversal tag with obj: type *interface {}, value 0xc0000442c0
panic: reflect: NumField of non-struct type interface {}

goroutine 1 [running]:
reflect.(*rtype).NumField(0xec2d20)
    C:/Program Files/Go/src/reflect/type.go:1015 +0xc8
main.traversalTag({0xebd9e0, 0xc0000442c0})
    d:/Coding/Golang/demo/demo.go:31 +0x1cb
main.tryMapWithReflect({0xec3d40, 0xc00007a480})
    d:/Coding/Golang/demo/demo.go:48 +0x2c9
main.main()
    d:/Coding/Golang/demo/demo.go:54 +0x38
Process 8716 has exited with status 2
dlv dap (11448) exited with code: 0

有人能提示如何使用原始类型信息获取映射成员的指针吗？

谢谢你，曼托