1. fix 4.4 2. moved device tree to linux-elphel

conf/machine/elphel393.conf

@@ -16,7 +16,7 @@ UBOOT_MACHINE = "elphel393_config"
 SERIAL_CONSOLE = "115200 ttyPS0"
 
 MACHINE_DEVICETREE := "\
-                       elphel393/elphel393.dts \
+                       elphel393.dts \
                       "
 MACHINE_KCONFIG := "common/elphel393_defconfig_${LINUX_VERSION}"
 

recipes-bsp/device-tree/device-tree.bbappend

 # add dtsi's
 SRC_URI += "file://*.dtsi"
 
+DEV_DIR ?= "${TOPDIR}/../../linux-elphel"
+
+python do_unpack(){
+    DEV_DIR = d.getVar('DEV_DIR', True)
+    MACHINE = d.getVar('MACHINE', True)
+    WORKDIR = d.getVar('WORKDIR', True)
+    
+    if os.path.isdir(DEV_DIR):
+        print("Found DEV_DIR, skipping something")
+        DTS_PATH = DEV_DIR+"/src/arch/arm/boot/dts"
+        MACHINE_DTS = DTS_PATH+"/"+MACHINE+".dts"
+        if os.path.isfile(MACHINE_DTS):
+            print("Machine device tree found: "+MACHINE+".dts")
+            d.setVar('MACHINE_DEVICETREE',MACHINE+".dts")
+            if not os.path.isdir(WORKDIR+"/devicetree"):
+                import subprocess
+                cmd = "ln -sf "+DTS_PATH+" "+WORKDIR+"/devicetree"
+                try:
+                    res = subprocess.check_output(cmd,stderr=subprocess.STDOUT,shell=True)
+                except subprocess.CalledProcessError as e:
+                    res = "error_"+e.returncode
+    else:
+        bb.build.exec_func('base_do_unpack', d)
+}
+
 do_deploy(){
 	for DTS_FILE in ${DEVICETREE}; do
 		DTS_NAME=`basename ${DTS_FILE} | awk -F "." '{print $1}'`
@@ -42,7 +67,7 @@ do_compile() {
 	for DTS_FILE in ${DEVICETREE}; do
 		DTS_NAME=`basename ${DTS_FILE} | awk -F "." '{print $1}'`
 		for RLOC in ${PRODUCTION_ROOT_LOCATION}; do
-			ln -sf ${WORKDIR}/devicetree/bootargs-${RLOC}.dtsi ${WORKDIR}/devicetree/bootargs.dtsi
+			ln -sf ${WORKDIR}/devicetree/${MACHINE}-bootargs-${RLOC}.dtsi ${WORKDIR}/devicetree/bootargs.dtsi
 			dtc -I dts -O dtb ${DEVICETREE_FLAGS} -o ${DTS_NAME}_${RLOC}.dtb ${DTS_FILE}
 		done
 	done

recipes-kernel/linux/config/elphel393.cfg

@@ -82,3 +82,22 @@ CONFIG_RTL8192CU=y
 CONFIG_LEGACY_PTYS=y
 
 CONFIG_OVERLAY_FS=y
+
+# config CPU_SW_DOMAIN_PAN
+# 	bool "Enable use of CPU domains to implement privileged no-access"
+# 	depends on MMU && !ARM_LPAE
+# 	default y
+# 	help
+# 	  Increase kernel security by ensuring that normal kernel accesses
+# 	  are unable to access userspace addresses.  This can help prevent
+# 	  use-after-free bugs becoming an exploitable privilege escalation
+# 	  by ensuring that magic values (such as LIST_POISON) will always
+# 	  fault when dereferenced.
+# 
+# 	  CPUs with low-vector mappings use a best-efforts implementation.
+# 	  Their lower 1MB needs to remain accessible for the vectors, but
+# 	  the remainder of userspace will become appropriately inaccessible.
+#
+# 1. https://github.com/raspberrypi/linux/pull/1178#issuecomment-163651327
+# 2. http://www.gossamer-threads.com/lists/linux/kernel/2317439
+CONFIG_CPU_SW_DOMAIN_PAN=n