[PATCH] serial: cpm_uart: call cpm_muram_init before registering console

[Christophe Leroy]

Le 13/02/2020 à 12:43, Rasmus Villemoes a écrit :
> Christophe reports that powerpc 8xx silently fails to 5.6-rc1. It turns
> out I was wrong about nobody relying on the lazy initialization of the
> cpm/qe muram in commit b6231ea2b3c6 (soc: fsl: qe: drop broken lazy
> call of cpm_muram_init()).
> 
> Rather than reinstating the somewhat dubious lazy call (initializing a
> currently held spinlock, and implicitly doing a GFP_KERNEL under that
> spinlock), make sure that cpm_muram_init() is called early enough - I
> thought the calls from the subsys_initcalls were good enough, but when
> used by console drivers, that's obviously not the
> case. cpm_muram_init() is safe to call twice (there's an early return
> if it is already initialized), so keep the call from cpm_init() - in
> case SERIAL_CPM_CONSOLE=n.
> 
> Reported-by: Christophe Leroy <christophe.leroy at c-s.fr>
> Fixes: b6231ea2b3c6 (soc: fsl: qe: drop broken lazy call of cpm_muram_init())
> Signed-off-by: Rasmus Villemoes <linux at rasmusvillemoes.dk>

Tested-by: Christophe Leroy <christophe.leroy at c-s.fr>

> ---
> 
> Christophe, can I get you to add a formal Tested-by?
> 
> I'm not sure which tree this should go through.
> 
>   drivers/tty/serial/cpm_uart/cpm_uart_core.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
> index 19d5a4cf29a6..d4b81b06e0cb 100644
> --- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c
> +++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
> @@ -1373,6 +1373,7 @@ static struct console cpm_scc_uart_console = {
>   
>   static int __init cpm_uart_console_init(void)
>   {
> +	cpm_muram_init();
>   	register_console(&cpm_scc_uart_console);
>   	return 0;
>   }
>