关于内核中一个Kconfig文件的问题

我把driver文件夹下的Kconfig文件进行了修改，可是运行make menuconfig的时候发现毫无变化，求指点啊。

例如，原driver文件夹下的Kconfig文件如下：

# drivers/Kconfig

menu "Device Drivers"

source "drivers/base/Kconfig"

source "drivers/connector/Kconfig"

source "drivers/mtd/Kconfig"

source "drivers/of/Kconfig"

source "drivers/parport/Kconfig"

source "drivers/pnp/Kconfig"

source "drivers/block/Kconfig"

# misc before ide - BLK_DEV_SGIIOC4 depends on SGI_IOC4

source "drivers/misc/Kconfig"

source "drivers/ide/Kconfig"

source "drivers/scsi/Kconfig"

source "drivers/ata/Kconfig"

source "drivers/md/Kconfig"

source "drivers/message/fusion/Kconfig"

source "drivers/ieee1394/Kconfig"

source "drivers/message/i2o/Kconfig"

source "drivers/macintosh/Kconfig"

source "drivers/net/Kconfig"

source "drivers/isdn/Kconfig"

source "drivers/telephony/Kconfig"

# input before char - char/joystick depends on it. As does USB.

source "drivers/input/Kconfig"

source "drivers/char/Kconfig"

source "drivers/i2c/Kconfig"

source "drivers/spi/Kconfig"

source "drivers/gpio/Kconfig"

source "drivers/w1/Kconfig"

source "drivers/power/Kconfig"

source "drivers/hwmon/Kconfig"

source "drivers/thermal/Kconfig"

source "drivers/watchdog/Kconfig"

source "drivers/ssb/Kconfig"

source "drivers/mfd/Kconfig"

source "drivers/regulator/Kconfig"

source "drivers/media/Kconfig"

source "drivers/video/Kconfig"

source "sound/Kconfig"

source "drivers/hid/Kconfig"

source "drivers/usb/Kconfig"

source "drivers/uwb/Kconfig"

source "drivers/mmc/Kconfig"

source "drivers/memstick/Kconfig"

source "drivers/leds/Kconfig"

source "drivers/accessibility/Kconfig"

source "drivers/infiniband/Kconfig"

source "drivers/edac/Kconfig"

source "drivers/rtc/Kconfig"

source "drivers/dma/Kconfig"

source "drivers/dca/Kconfig"

source "drivers/auxdisplay/Kconfig"

source "drivers/uio/Kconfig"

source "drivers/xen/Kconfig"

source "drivers/staging/Kconfig"
endmenu

为了只在菜单中现在字符型设备，我将此文件删减为：
# drivers/Kconfig

menu "Device Drivers"

source "drivers/char/Kconfig"

endmenu
不管这样删减是否是正确的，可是依次运行指令make clean , make menuconfig后进入 Device Drivers选项后依然还有许多驱动选项可以选择，而并不会只出现Character devices这一个驱动选项。

不知道是不是因为不允许修改driver下的kconfig文件啊？


------解决方案--------------------
建议首先看下Makefile是否有问题。
然后检查下.config文件是否你修改过的东西在make的时候被修改回来了。