| Message ID | 1367962765-13912-1-git-send-email-khilman@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Kevin Hilman <khilman@linaro.org> [130507 14:44]: > If DEBUG_LL and earlyprintk are enabled, and omap-serial.c is compiled > as a module, the kernel boot hangs early as the clocks for serial port > are cut while earlyprintk still uses the port. > > The problem is a race between the late_initcall for omap_device (which > idles devices that have no drivers) and the late_initcall in > kernel/printk.c which turns off the earlyconsole. Any printks > that happen between this omap_device late initcall and the earlyconsole > late initcall will crash when accessing the UART. > > The fix is to ensure the omap_device initcall happens after the > earlyconsole initcall. > > Reported-by: Tony Lindgren <tony@atomide.com> > Signed-off-by: Kevin Hilman <khilman@linaro.org> Thanks applying into omap-for-v3.10/fixes. Tony > --- > Based on v3.9-rc8 > > arch/arm/mach-omap2/omap_device.c | 2 +- > arch/arm/mach-omap2/soc.h | 1 + > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c > index 381be7a..2d20d69 100644 > --- a/arch/arm/mach-omap2/omap_device.c > +++ b/arch/arm/mach-omap2/omap_device.c > @@ -879,4 +879,4 @@ static int __init omap_device_late_init(void) > bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle); > return 0; > } > -omap_late_initcall(omap_device_late_init); > +omap_late_initcall_sync(omap_device_late_init); > diff --git a/arch/arm/mach-omap2/soc.h b/arch/arm/mach-omap2/soc.h > index c62116b..de88611 100644 > --- a/arch/arm/mach-omap2/soc.h > +++ b/arch/arm/mach-omap2/soc.h > @@ -494,6 +494,7 @@ level(__##fn); > #define omap_subsys_initcall(fn) omap_initcall(subsys_initcall, fn) > #define omap_device_initcall(fn) omap_initcall(device_initcall, fn) > #define omap_late_initcall(fn) omap_initcall(late_initcall, fn) > +#define omap_late_initcall_sync(fn) omap_initcall(late_initcall_sync, fn) > > #endif /* __ASSEMBLY__ */ > > -- > 1.8.2 >
diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c index 381be7a..2d20d69 100644 --- a/arch/arm/mach-omap2/omap_device.c +++ b/arch/arm/mach-omap2/omap_device.c @@ -879,4 +879,4 @@ static int __init omap_device_late_init(void) bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle); return 0; } -omap_late_initcall(omap_device_late_init); +omap_late_initcall_sync(omap_device_late_init); diff --git a/arch/arm/mach-omap2/soc.h b/arch/arm/mach-omap2/soc.h index c62116b..de88611 100644 --- a/arch/arm/mach-omap2/soc.h +++ b/arch/arm/mach-omap2/soc.h @@ -494,6 +494,7 @@ level(__##fn); #define omap_subsys_initcall(fn) omap_initcall(subsys_initcall, fn) #define omap_device_initcall(fn) omap_initcall(device_initcall, fn) #define omap_late_initcall(fn) omap_initcall(late_initcall, fn) +#define omap_late_initcall_sync(fn) omap_initcall(late_initcall_sync, fn) #endif /* __ASSEMBLY__ */
If DEBUG_LL and earlyprintk are enabled, and omap-serial.c is compiled as a module, the kernel boot hangs early as the clocks for serial port are cut while earlyprintk still uses the port. The problem is a race between the late_initcall for omap_device (which idles devices that have no drivers) and the late_initcall in kernel/printk.c which turns off the earlyconsole. Any printks that happen between this omap_device late initcall and the earlyconsole late initcall will crash when accessing the UART. The fix is to ensure the omap_device initcall happens after the earlyconsole initcall. Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Kevin Hilman <khilman@linaro.org> --- Based on v3.9-rc8 arch/arm/mach-omap2/omap_device.c | 2 +- arch/arm/mach-omap2/soc.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-)