“模块中的未知符号"；尽管有EXPORT_SYMBOL，但仍可插入模块 [英] "Unknown symbol in module" on module insertion despite EXPORT_SYMBOL

问题描述

我正在尝试编译并插入r8169 realtek以太网驱动程序.我的内核版本是

I am trying to compile and insert the r8169 realtek ethernet driver. My kernel version is

ebin@sony:~$ uname -r
4.2.0-rc3-custom

我的本​​地磁盘上有完整的源代码，该磁盘用于安装当前内核.当我运行make -C /lib/modules/ uname -r /build M= pwd modules
时，模块编译成功 但是当我插入模块时，它会显示

I have the full source of the same in my local disk, which is used to install the current kernel. The module compiles successfully when I run make -C /lib/modules/uname -r/build M=pwdmodules
but when I insert the module, it shows

ebin@sony:~/linux_testing/linux-stable/drivers/net/ethernet/realtek$ sudo insmod r8169.ko
insmod: ERROR: could not insert module r8169.ko: Unknown symbol in module
ebin@sony:~/linux_testing/linux-stable/drivers/net/ethernet/realtek$ dmesg
[16717.311216] r8169: Unknown symbol mii_ethtool_gset (err 0)

浏览源代码时，我发现

EXPORT_SYMBOL(mii_ethtool_gset);

已在mii.c中导出.因此，我想这不是未导出符号的问题.让我知道是否需要提供其他信息.请帮忙.

already exported in the mii.c. So I guess it is not the problem of unexported symbol. Let me know if I have to provide any other info. Please help.

推荐答案

正如Vadim Stupakov在评论中所说，将Module.symvers文件放在模块源目录中解决了我的问题.从此文档

As Vadim Stupakov said in the comment, Putting the Module.symvers file in the module source directory fixed my issue. From this documentation

Module versioning is enabled by the CONFIG_MODVERSIONS tag, and is used
as a simple ABI consistency check. A CRC value of the full prototype
for an exported symbol is created. When a module is loaded/used, the
CRC values contained in the kernel are compared with similar values in
the module. if they are not equal, the kernel refuses to load the
module. 
Module.symvers contains a list of all exported symbols from a kernel
build.

据我了解，Module.symvers是在make modules上创建的.我错过了那个文件.当我将适当的Module.symvers放在模块构建目录中时，该模块将按预期运行，而不会出现任何错误.

As per my understanding, Module.symvers is created on make modules. I missed out that file. When I put the appropriate Module.symvers in the module build directory, the module works as I expected without any errors.

这篇关于“模块中的未知符号"；尽管有EXPORT_SYMBOL，但仍可插入模块的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！