Hi Just another update on this stuff. I noticed that there has been a patch added* with spinlocks to the imx.c serial driver. I reverted this patch and now my serialfuz programm "only" kills the serial port with a not so nice oom condition. But at least it does not show the runaway interrupt problem. Best regards Tim * its 86236252d2449313bdbac790023cbc957bf6e426 commit 9ec1882df244c4ee1baa692676fef5e8b0f5487d upstream. -- 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