kernel: use oldnoconfig before yes '' | make oldconfig
When using a defconfig, using yes '' | make oldconfig may not result in
the correct configuration being set. For example:
$ ARCH=mips make qi_lb60_defconfig
#
# configuration written to .config
#
$ grep USB_ETH .config
CONFIG_USB_ETH=y
# CONFIG_USB_ETH_RNDIS is not set
# CONFIG_USB_ETH_EEM is not set
$ cp arch/mips/configs/qi_lb60_defconfig .config
$ yes '' | make ARCH=mips oldconfig
[...]
$ grep USB_ETH .config
CONFIG_USB_ETH=m
# CONFIG_USB_ETH_RNDIS is not set
# CONFIG_USB_ETH_EEM is not set
Using make olddefconfig solves that but we'll use the oldnoconfig alias
for backward compatibility with older kernels.
$ cp arch/mips/configs/qi_lb60_defconfig .config
$ make ARCH=mips oldnoconfig
scripts/kconfig/conf --olddefconfig Kconfig
#
# configuration written to .config
#
$ grep USB_ETH .config
CONFIG_USB_ETH=y
# CONFIG_USB_ETH_RNDIS is not set
# CONFIG_USB_ETH_EEM is not set
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>