Re: [PATCH] tty: serial: msm_serial: Remove __init from msm_console_setup()

From: Bjorn Andersson
Date: Sun Feb 17 2019 - 02:20:01 EST


On Sat 16 Feb 21:05 PST 2019, Jeffrey Hugo wrote:

> Due to the complexities of modern Qualcomm SoCs, about a half dozen drivers
> must successfully probe before the clocks for the console are present, and
> the console can successfully probe. Depending on several random factors
> such as probe order and modules vs builtin, msm_serial may not be able to
> successfully probe for some, at which point, __init annotated functions
> may become unmapped. If this occurs, msm_console_setup() will be called
> from the probe path, but will no longer exist, resulting in a kernel
> panic.
>
> Resolve this issue by removing the __init annotation from
> msm_console_setup().

I'm pretty sure I've stumbled upon this several times without knowing
what hit me.

Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Regards,
Bjorn

>
> Signed-off-by: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx>
> ---
> drivers/tty/serial/msm_serial.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
> index 736b74f..1090960 100644
> --- a/drivers/tty/serial/msm_serial.c
> +++ b/drivers/tty/serial/msm_serial.c
> @@ -1634,7 +1634,7 @@ static void msm_console_write(struct console *co, const char *s,
> __msm_console_write(port, s, count, msm_port->is_uartdm);
> }
>
> -static int __init msm_console_setup(struct console *co, char *options)
> +static int msm_console_setup(struct console *co, char *options)
> {
> struct uart_port *port;
> int baud = 115200;
> --
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> Qualcomm Technologies, Inc. is a member of the
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>