arm64: link with -z norelro regardless of CONFIG_RELOCATABLE

[GitHub/LineageOS/G12/android_kernel_amlogic_linux-4.9.git] / arch / arm64 / Makefile

diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 3894c52cbbe44e977bed9a2846521c9d530f7f50..2f0e229e9f467a61b04713faa56c35566847c594 100644 (file)
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -10,7 +10,7 @@
 #
 # Copyright (C) 1995-2001 by Russell King
 
-LDFLAGS_vmlinux        :=--no-undefined -X
+LDFLAGS_vmlinux        :=--no-undefined -X -z norelro
 CPPFLAGS_vmlinux.lds = -DTEXT_OFFSET=$(TEXT_OFFSET)
 GZFLAGS                :=-9
 
@@ -18,7 +18,7 @@ ifeq ($(CONFIG_RELOCATABLE), y)
 # Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour
 # for relative relocs, since this leads to better Image compression
 # with the relocation offsets always being zero.
-LDFLAGS_vmlinux                += -pie -shared -Bsymbolic \
+LDFLAGS_vmlinux                += -shared -Bsymbolic -z notext \
                        $(call ld-option, --no-apply-dynamic-relocs)
 endif
 
@@ -58,20 +58,56 @@ else
 KBUILD_CFLAGS  += -mgeneral-regs-only
 endif
 KBUILD_CFLAGS  += $(lseinstr)
+
+ifeq ($(CONFIG_COMPAT_VDSO), y)
+  CROSS_COMPILE_ARM32 ?= $(CONFIG_CROSS_COMPILE_ARM32:"%"=%)
+   # Check that the user has provided a valid prefix for the 32-bit toolchain.
+  # To prevent selecting the system $(cc-name) by default, the prefix is not
+  # allowed to be empty, unlike CROSS_COMPILE. In the unlikely event that the
+  # system $(cc-name) is actually the 32-bit ARM compiler to be used, the
+  # variable can be set to the dirname (e.g. CROSS_COMPILE_ARM32=/usr/bin/).
+  # Note: this Makefile is read both before and after regenerating the config
+  # (if needed). Any warning appearing before the config has been regenerated
+  # should be ignored. If the error is triggered and you set
+  # CONFIG_CROSS_COMPILE_ARM32, set CROSS_COMPILE_ARM32 to an appropriate value
+  # when invoking make and fix CONFIG_CROSS_COMPILE_ARM32.
+  ifeq ($(CROSS_COMPILE_ARM32),)
+    $(error CROSS_COMPILE_ARM32 not defined or empty, the compat vDSO will not be built)
+  else ifeq ($(cc-name),clang)
+    export CLANG_TRIPLE_ARM32 ?= $(CROSS_COMPILE_ARM32)
+    export CLANG_TARGET_ARM32 := --target=$(notdir $(CLANG_TRIPLE_ARM32:%-=%))
+    export GCC_TOOLCHAIN32_DIR := $(dir $(shell which $(CROSS_COMPILE_ARM32)ld))
+    export GCC_TOOLCHAIN32 := $(realpath $(GCC_TOOLCHAIN32_DIR)/..)
+    export CLANG_PREFIX32 := --prefix=$(GCC_TOOLCHAIN32_DIR)
+    export CLANG_GCC32_TC := --gcc-toolchain=$(GCC_TOOLCHAIN32)
+    export CONFIG_VDSO32 := y
+    vdso32 := -DCONFIG_VDSO32=1
+  else ifeq ($(shell which $(CROSS_COMPILE_ARM32)$(cc-name) 2> /dev/null),)
+    $(error $(CROSS_COMPILE_ARM32)$(cc-name) not found, check CROSS_COMPILE_ARM32)
+  else
+    export CROSS_COMPILE_ARM32
+    export CONFIG_VDSO32 := y
+    vdso32 := -DCONFIG_VDSO32=1
+  endif
+endif
+
+KBUILD_CFLAGS  += $(vdso32)
 KBUILD_CFLAGS  += -fno-asynchronous-unwind-tables
 KBUILD_CFLAGS  += $(call cc-option, -mpc-relative-literal-loads)
 KBUILD_CFLAGS  += -fno-pic
-KBUILD_AFLAGS  += $(lseinstr)
+KBUILD_AFLAGS  += $(lseinstr) $(vdso32)
 
 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 KBUILD_CPPFLAGS        += -mbig-endian
 AS             += -EB
-LD             += -EB
+# Prefer the baremetal ELF build target, but not all toolchains include
+LDFLAGS                += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
 UTS_MACHINE    := aarch64_be
 else
 KBUILD_CPPFLAGS        += -mlittle-endian
 AS             += -EL
-LD             += -EL
+# Same as above, prefer ELF but fall back to linux target if needed.
+LDFLAGS                += -EL $(call ld-option, -maarch64elf, -maarch64linux)
 UTS_MACHINE    := aarch64
 endif
 
@@ -98,7 +134,7 @@ TEXT_OFFSET := $(shell awk "BEGIN {srand(); printf \"0x%06x\n\", \
                 int(2 * 1024 * 1024 / (2 ^ $(CONFIG_ARM64_PAGE_SHIFT)) * \
                 rand()) * (2 ^ $(CONFIG_ARM64_PAGE_SHIFT))}")
 else
-TEXT_OFFSET := 0x00080000
+TEXT_OFFSET := 0x01080000
 endif
 
 ifeq ($(cc-name),clang)
@@ -144,9 +180,16 @@ Image.%: Image
 zinstall install:
        $(Q)$(MAKE) $(build)=$(boot) $@
 
-%.dtb: scripts
+amlogic/%.dtb: scripts
        $(Q)$(MAKE) $(build)=$(boot)/dts $(boot)/dts/$@
 
+%.dtb: scripts
+       $(Q)$(MAKE) $(build)=$(boot)/dts/amlogic $(boot)/dts/amlogic/$@
+ifeq ($(CONFIG_AMLOGIC_MODIFY),y)
+%.dtbo: scripts
+       $(Q)$(MAKE) $(build)=$(boot)/dts/amlogic $(boot)/dts/amlogic/$@
+endif
+
 PHONY += dtbs dtbs_install
 
 dtbs: prepare scripts
@@ -177,6 +220,8 @@ ifeq ($(KBUILD_EXTMOD),)
 prepare: vdso_prepare
 vdso_prepare: prepare0
        $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h
+       $(if $(CONFIG_VDSO32),$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 \
+                                         include/generated/vdso32-offsets.h)
 endif
 
 define archhelp