On Fri, 25 Aug 2017 16:14:51 +0300 Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com> wrote: > In the current implementation we take the first console that > registers if we didn't select one. > > But if we specify console via "stdout-path" property in device tree > we don't want first console that registers here to be selected. > Otherwise we may choose wrong console - for example if some console > is registered earlier than console is pointed in "stdout-path" > property because console pointed in "stdout-path" property can be add as > preferred quite late - when it's driver is probed. > > Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com> > --- > kernel/printk/printk.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c > index 512f7c2..23262c1 100644 > --- a/kernel/printk/printk.c > +++ b/kernel/printk/printk.c > @@ -26,6 +26,7 @@ > #include <linux/nmi.h> > #include <linux/module.h> > #include <linux/moduleparam.h> > +#include <linux/of.h> > #include <linux/delay.h> > #include <linux/smp.h> > #include <linux/security.h> > @@ -2431,6 +2432,16 @@ void register_console(struct console *newcon) > if (!has_preferred || bcon || !console_drivers) > has_preferred = preferred_console >= 0; > > + > + /* > + * If we specify console via "stdout-path" property in device tree > + * we don't want first console that registers here to be selected. > + */ > +#ifdef CONFIG_OF > + if (of_stdout) > + has_preferred = true; > +#endif To remove the #ifdef from the code, could the of.h move #ifdef CONFIG_OF Above the extern declarations of of_stdout and friends, and then have: #else /* !CONFIG_OF */ #define of_stdout NULL #endif Then we could just have: if (of_stdout) has_preferred = true; without the ifdefs. -- Steve > + > /* > * See if we want to use this console driver. If we > * didn't select a console we take the first one
