三个方法

1. proc文件系统
2. ubunut debain
3. 红帽等

proc文件系统

/proc/config.gz

This file shows you the compile-time configuration settings for the kernel (gzip compressed, use zcat or zless to see its contents). It is available only if you enable it using CONFIG_IKCONFIG_PROC when you compile.

Say you want to upgrade to the next available kernel. Your current kernel works fine, so you'd like to use the same parameters, but you accidentally lost your original .config configuration file. Simplyzcat /proc/config.gz > /usr/src/linux/.config and you're ready to go.

Example output:

Automatically generated make config: don't edit

Linux kernel version: 2.6.17

Sat Jul 15 17:01:24 2006

CONFIG_X86_32=y

CONFIG_SEMAPHORE_SLEEPERS=y

CONFIG_X86=y

CONFIG_MMU=y

CONFIG_GENERIC_ISA_DMA=y

CONFIG_GENERIC_IOMAP=y

CONFIG_GENERIC_HWEIGHT=y

CONFIG_ARCH_MAY_HAVE_PC_FDC=y

CONFIG_DMI=y

#zcat /proc/config.gz

需要开启内核配置项CONFIG_IKCONFIG才会生成这个文件

ubuntu

1. 文件下查看

   /usr/src/linux-headers-VERSION-generic/.config

2. 从系统/boot目录下获取

[root@localhost ~]# uname -r4.9.77[root@localhost ~]# ls /boot/config-4.9.77-30.el7.x86_64                              System.mapgrub                                                     System.map-4.9.77grub2                                                    System.map-4.9.77-30.el7.x86_64initramfs-0-rescue-d5e5083a18b24f4db74d0c0f71770f64.img  System.map-4.9.77.oldinitramfs-4.9.77.img                                     vmlinuzinitramfs-4.9.77kdump.img                                vmlinuz-0-rescue-d5e5083a18b24f4db74d0c0f71770f64initrd-plymouth.img                                      vmlinuz-4.9.77symvers-4.9.77-30.el7.x86_64.gz

3.从系统/usr/src/kernel目录下获取

[root@localhost ~]# uname -r4.9.77[root@localhost ~]# cd /usr/src/kernels[root@localhost kernels]# ls4.9.77-30.el7.x86_64[root@localhost kernels]# cd 4.9.77-30.el7.x86_64/[root@localhost 4.9.77-30.el7.x86_64]# ls -a.     block   .config      drivers   include  Kconfig  Makefile        net      security    tools..    certs   .config.old  firmware  init     kernel   mm              samples  sound       usrarch  config  crypto       fs        ipc      lib      Module.symvers  scripts  System.map  virt

如上所示，当前内核的编译配置文件为：.config