On Sat, Sep 19, 2020 at 10:26:38AM +0800, Yang Yingliang wrote: > Hi, > > On 2020/9/18 19:16, Greg KH wrote: > > On Fri, Sep 18, 2020 at 05:13:05PM +0800, Yang Yingliang wrote: > > > Fix the link error by selecting SERIAL_CORE_CONSOLE. > > > > > > aarch64-linux-gnu-ld: drivers/tty/serial/imx_earlycon.o: in function `imx_uart_console_early_write': > > > imx_earlycon.c:(.text+0x84): undefined reference to `uart_console_write' > > > > > > Reported-by: Hulk Robot <hulkci@xxxxxxxxxx> > > > Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx> > > > --- > > > drivers/tty/serial/Kconfig | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > > > index 9631ccf43378..1044fc387691 100644 > > > --- a/drivers/tty/serial/Kconfig > > > +++ b/drivers/tty/serial/Kconfig > > > @@ -521,6 +521,7 @@ config SERIAL_IMX_EARLYCON > > > depends on ARCH_MXC || COMPILE_TEST > > > depends on OF > > > select SERIAL_EARLYCON > > > + select SERIAL_CORE_CONSOLE > > > help > > > If you have enabled the earlycon on the Freescale IMX > > > CPU you can make it the earlycon by answering Y to this option. > > > -- > > > 2.25.1 > > > > > What caused this build error to start happening? Any pointers to the > > specific commit? > > It's start from 699cc4dfd140 ("tty: serial: imx: add imx earlycon driver"), > the driver > > uses the uart_console_write(), but SERIAL_CORE_CONSOLE is not selected, so > uart_console_write > > is not defined, then we get the error. Great, can you add a Fixes: line to the patch and resend it with this information added to the changelog text? Always include this type of information if at all possible. thanks, greg k-h