Thomas, A typo in preempt-irqs-core.patch, where IRQF_TIMER is changed to _IRQF_TIMER but called later as __IRQF_TIMER. Here's a patch to compile, but not sure if you want one or two underscores. With these two paches, -rt3 is building/booting for ARM/OMAP1. Kevin Index: linux-2.6/include/linux/interrupt.h =================================================================== --- linux-2.6.orig/include/linux/interrupt.h +++ linux-2.6/include/linux/interrupt.h @@ -52,7 +52,7 @@ #define IRQF_SAMPLE_RANDOM 0x00000040 #define IRQF_SHARED 0x00000080 #define IRQF_PROBE_SHARED 0x00000100 -#define _IRQF_TIMER 0x00000200 +#define __IRQF_TIMER 0x00000200 #define IRQF_PERCPU 0x00000400 #define IRQF_NOBALANCING 0x00000800 #define IRQF_IRQPOLL 0x00001000 - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html