[PATCH] serial: cpm_uart: call cpm_muram_init before registering console
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
Fixes: b6231ea2b3c6 (soc: fsl: qe: drop broken lazy call of cpm_muram_init())
Signed-off-by: Rasmus Villemoes
---
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;
}
--
2.23.0
Re: [PATCH] serial: cpm_uart: call cpm_muram_init before registering console
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
Fixes: b6231ea2b3c6 (soc: fsl: qe: drop broken lazy call of cpm_muram_init())
Signed-off-by: Rasmus Villemoes
Tested-by: Christophe Leroy
---
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;
}
Re: [PATCH] serial: cpm_uart: call cpm_muram_init before registering console
On Thu, Feb 13, 2020 at 12:43:42PM +0100, Rasmus Villemoes wrote: > 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 > Fixes: b6231ea2b3c6 (soc: fsl: qe: drop broken lazy call of cpm_muram_init()) > Signed-off-by: Rasmus Villemoes > --- > > Christophe, can I get you to add a formal Tested-by? > > I'm not sure which tree this should go through. I can take it, thanks. greg k-h
RE: [PATCH] serial: cpm_uart: call cpm_muram_init before registering console
> -Original Message-
> From: Rasmus Villemoes
> Sent: Thursday, February 13, 2020 5:44 AM
> To: Greg Kroah-Hartman ; Jiri Slaby
> ; Timur Tabi ; Leo Li
> ; Rasmus Villemoes
> Cc: Qiang Zhao ; linuxppc-dev@lists.ozlabs.org; Scott
> Wood ; Christophe Leroy ;
> linux-ser...@vger.kernel.org; linux-ker...@vger.kernel.org
> Subject: [PATCH] serial: cpm_uart: call cpm_muram_init before registering
> console
>
> 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
> Fixes: b6231ea2b3c6 (soc: fsl: qe: drop broken lazy call of cpm_muram_init())
> Signed-off-by: Rasmus Villemoes
Acked-by: Li Yang
> ---
>
> 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;
> }
> --
> 2.23.0
