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

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

[Jeffrey Hugo]

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().

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
---
 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;
-- 
Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

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

[Bjorn Andersson]

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@linaro.org>

Regards,
Bjorn

> 
> Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
> ---
>  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;
> -- 
> Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the
> Code Aurora Forum, a Linux Foundation Collaborative Project.
>