kernel: add linux 4.9 support

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Tim Harvey <tharvey@gateworks.com> [fixes]

1 files changed, 403 insertions, 0 deletions

diff --git a/target/linux/generic/patches-4.9/220-gc_sections.patch b/target/linux/generic/patches-4.9/220-gc_sections.patch
new file mode 100644
index 0000000000..570083a509
--- /dev/null
+++ b/target/linux/generic/patches-4.9/220-gc_sections.patch
@@ -0,0 +1,403 @@
+From: Felix Fietkau <nbd@nbd.name>
+
+use -ffunction-sections, -fdata-sections and --gc-sections
+
+In combination with kernel symbol export stripping this significantly reduces
+the kernel image size. Used on both ARM and MIPS architectures.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+Signed-off-by: Jonas Gorski <jogo@openwrt.org>
+Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
+---
+
+--- a/arch/mips/kernel/vmlinux.lds.S
++++ b/arch/mips/kernel/vmlinux.lds.S
+@@ -71,7 +71,7 @@ SECTIONS
+ 	/* Exception table for data bus errors */
+ 	__dbe_table : {
+ 		__start___dbe_table = .;
+-		*(__dbe_table)
++		KEEP(*(__dbe_table))
+ 		__stop___dbe_table = .;
+ 	}
+ 
+@@ -121,7 +121,7 @@ SECTIONS
+ 	. = ALIGN(4);
+ 	.mips.machines.init : AT(ADDR(.mips.machines.init) - LOAD_OFFSET) {
+ 		__mips_machines_start = .;
+-		*(.mips.machines.init)
++		KEEP(*(.mips.machines.init))
+ 		__mips_machines_end = .;
+ 	}
+ 
+--- a/include/asm-generic/vmlinux.lds.h
++++ b/include/asm-generic/vmlinux.lds.h
+@@ -114,7 +114,7 @@
+ #ifdef CONFIG_KPROBES
+ #define KPROBE_BLACKLIST()	. = ALIGN(8);				      \
+ 				VMLINUX_SYMBOL(__start_kprobe_blacklist) = .; \
+-				*(_kprobe_blacklist)			      \
++				KEEP(*(_kprobe_blacklist))		      \
+ 				VMLINUX_SYMBOL(__stop_kprobe_blacklist) = .;
+ #else
+ #define KPROBE_BLACKLIST()
+@@ -123,10 +123,10 @@
+ #ifdef CONFIG_EVENT_TRACING
+ #define FTRACE_EVENTS()	. = ALIGN(8);					\
+ 			VMLINUX_SYMBOL(__start_ftrace_events) = .;	\
+-			*(_ftrace_events)				\
++			KEEP(*(_ftrace_events))				\
+ 			VMLINUX_SYMBOL(__stop_ftrace_events) = .;	\
+ 			VMLINUX_SYMBOL(__start_ftrace_enum_maps) = .;	\
+-			*(_ftrace_enum_map)				\
++			KEEP(*(_ftrace_enum_map))			\
+ 			VMLINUX_SYMBOL(__stop_ftrace_enum_maps) = .;
+ #else
+ #define FTRACE_EVENTS()
+@@ -147,7 +147,7 @@
+ #ifdef CONFIG_FTRACE_SYSCALLS
+ #define TRACE_SYSCALLS() . = ALIGN(8);					\
+ 			 VMLINUX_SYMBOL(__start_syscalls_metadata) = .;	\
+-			 *(__syscalls_metadata)				\
++			 KEEP(*(__syscalls_metadata))			\
+ 			 VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
+ #else
+ #define TRACE_SYSCALLS()
+@@ -169,8 +169,8 @@
+ #define _OF_TABLE_1(name)						\
+ 	. = ALIGN(8);							\
+ 	VMLINUX_SYMBOL(__##name##_of_table) = .;			\
+-	*(__##name##_of_table)						\
+-	*(__##name##_of_table_end)
++	KEEP(*(__##name##_of_table))					\
++	KEEP(*(__##name##_of_table_end))
+ 
+ #define CLKSRC_OF_TABLES()	OF_TABLE(CONFIG_CLKSRC_OF, clksrc)
+ #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip)
+@@ -193,7 +193,7 @@
+ #define KERNEL_DTB()							\
+ 	STRUCT_ALIGN();							\
+ 	VMLINUX_SYMBOL(__dtb_start) = .;				\
+-	*(.dtb.init.rodata)						\
++	KEEP(*(.dtb.init.rodata))					\
+ 	VMLINUX_SYMBOL(__dtb_end) = .;
+ 
+ /*
+@@ -214,16 +214,17 @@
+ 	/* implement dynamic printk debug */				\
+ 	. = ALIGN(8);                                                   \
+ 	VMLINUX_SYMBOL(__start___jump_table) = .;                       \
+-	*(__jump_table)                                                 \
++	KEEP(*(__jump_table))                                           \
+ 	VMLINUX_SYMBOL(__stop___jump_table) = .;                        \
+ 	. = ALIGN(8);							\
+ 	VMLINUX_SYMBOL(__start___verbose) = .;                          \
+-	*(__verbose)                                                    \
++	KEEP(*(__verbose))                                              \
+ 	VMLINUX_SYMBOL(__stop___verbose) = .;				\
+ 	LIKELY_PROFILE()		       				\
+ 	BRANCH_PROFILE()						\
+ 	TRACE_PRINTKS()							\
+-	TRACEPOINT_STR()
++	TRACEPOINT_STR()                                                \
++	*(.data.[a-zA-Z_]*)
+ 
+ /*
+  * Data section helpers
+@@ -291,35 +292,35 @@
+ 	/* PCI quirks */						\
+ 	.pci_fixup        : AT(ADDR(.pci_fixup) - LOAD_OFFSET) {	\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_early) = .;		\
+-		*(.pci_fixup_early)					\
++		KEEP(*(.pci_fixup_early))				\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_early) = .;		\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_header) = .;		\
+-		*(.pci_fixup_header)					\
++		KEEP(*(.pci_fixup_header))				\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_header) = .;		\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_final) = .;		\
+-		*(.pci_fixup_final)					\
++		KEEP(*(.pci_fixup_final))				\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_final) = .;		\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_enable) = .;		\
+-		*(.pci_fixup_enable)					\
++		KEEP(*(.pci_fixup_enable))				\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_enable) = .;		\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_resume) = .;		\
+-		*(.pci_fixup_resume)					\
++		KEEP(*(.pci_fixup_resume))				\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_resume) = .;		\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .;	\
+-		*(.pci_fixup_resume_early)				\
++		KEEP(*(.pci_fixup_resume_early))			\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .;	\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .;		\
+-		*(.pci_fixup_suspend)					\
++		KEEP(*(.pci_fixup_suspend))				\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .;		\
+ 		VMLINUX_SYMBOL(__start_pci_fixups_suspend_late) = .;	\
+-		*(.pci_fixup_suspend_late)				\
++		KEEP(*(.pci_fixup_suspend_late))			\
+ 		VMLINUX_SYMBOL(__end_pci_fixups_suspend_late) = .;	\
+ 	}								\
+ 									\
+ 	/* Built-in firmware blobs */					\
+ 	.builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {	\
+ 		VMLINUX_SYMBOL(__start_builtin_fw) = .;			\
+-		*(.builtin_fw)						\
++		KEEP(*(.builtin_fw))					\
+ 		VMLINUX_SYMBOL(__end_builtin_fw) = .;			\
+ 	}								\
+ 									\
+@@ -397,7 +398,7 @@
+ 									\
+ 	/* Kernel symbol table: strings */				\
+         __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) {	\
+-		KEEP(*(__ksymtab_strings))				\
++		*(__ksymtab_strings)					\
+ 	}								\
+ 									\
+ 	/* __*init sections */						\
+@@ -410,14 +411,14 @@
+ 	/* Built-in module parameters. */				\
+ 	__param : AT(ADDR(__param) - LOAD_OFFSET) {			\
+ 		VMLINUX_SYMBOL(__start___param) = .;			\
+-		*(__param)						\
++		KEEP(*(__param))					\
+ 		VMLINUX_SYMBOL(__stop___param) = .;			\
+ 	}								\
+ 									\
+ 	/* Built-in module versions. */					\
+ 	__modver : AT(ADDR(__modver) - LOAD_OFFSET) {			\
+ 		VMLINUX_SYMBOL(__start___modver) = .;			\
+-		*(__modver)						\
++		KEEP(*(__modver))					\
+ 		VMLINUX_SYMBOL(__stop___modver) = .;			\
+ 		. = ALIGN((align));					\
+ 		VMLINUX_SYMBOL(__end_rodata) = .;			\
+@@ -482,7 +483,7 @@
+ #define ENTRY_TEXT							\
+ 		ALIGN_FUNCTION();					\
+ 		VMLINUX_SYMBOL(__entry_text_start) = .;			\
+-		*(.entry.text)						\
++		KEEP(*(.entry.text))					\
+ 		VMLINUX_SYMBOL(__entry_text_end) = .;
+ 
+ #if defined(CONFIG_FUNCTION_GRAPH_TRACER) || defined(CONFIG_KASAN)
+@@ -520,7 +521,7 @@
+ 	. = ALIGN(align);						\
+ 	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {		\
+ 		VMLINUX_SYMBOL(__start___ex_table) = .;			\
+-		*(__ex_table)						\
++		KEEP(*(__ex_table))						\
+ 		VMLINUX_SYMBOL(__stop___ex_table) = .;			\
+ 	}
+ 
+@@ -536,9 +537,9 @@
+ #ifdef CONFIG_CONSTRUCTORS
+ #define KERNEL_CTORS()	. = ALIGN(8);			   \
+ 			VMLINUX_SYMBOL(__ctors_start) = .; \
+-			*(.ctors)			   \
++			KEEP(*(.ctors))			   \
+ 			*(SORT(.init_array.*))		   \
+-			*(.init_array)			   \
++			KEEP(*(.init_array))		   \
+ 			VMLINUX_SYMBOL(__ctors_end) = .;
+ #else
+ #define KERNEL_CTORS()
+@@ -595,7 +596,7 @@
+ #define SBSS(sbss_align)						\
+ 	. = ALIGN(sbss_align);						\
+ 	.sbss : AT(ADDR(.sbss) - LOAD_OFFSET) {				\
+-		*(.sbss)						\
++		*(.sbss .sbss.*)					\
+ 		*(.scommon)						\
+ 	}
+ 
+@@ -662,7 +663,7 @@
+ 	. = ALIGN(8);							\
+ 	__bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) {		\
+ 		VMLINUX_SYMBOL(__start___bug_table) = .;		\
+-		*(__bug_table)						\
++		KEEP(*(__bug_table))					\
+ 		VMLINUX_SYMBOL(__stop___bug_table) = .;			\
+ 	}
+ #else
+@@ -674,7 +675,7 @@
+ 	. = ALIGN(4);							\
+ 	.tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) {		\
+ 		VMLINUX_SYMBOL(__tracedata_start) = .;			\
+-		*(.tracedata)						\
++		KEEP(*(.tracedata))					\
+ 		VMLINUX_SYMBOL(__tracedata_end) = .;			\
+ 	}
+ #else
+@@ -691,7 +692,7 @@
+ #define INIT_SETUP(initsetup_align)					\
+ 		. = ALIGN(initsetup_align);				\
+ 		VMLINUX_SYMBOL(__setup_start) = .;			\
+-		*(.init.setup)						\
++		KEEP(*(.init.setup))					\
+ 		VMLINUX_SYMBOL(__setup_end) = .;
+ 
+ #define INIT_CALLS_LEVEL(level)						\
+--- a/arch/arm/kernel/vmlinux.lds.S
++++ b/arch/arm/kernel/vmlinux.lds.S
+@@ -17,7 +17,7 @@
+ #define PROC_INFO							\
+ 	. = ALIGN(4);							\
+ 	VMLINUX_SYMBOL(__proc_info_begin) = .;				\
+-	*(.proc.info.init)						\
++	KEEP(*(.proc.info.init))					\
+ 	VMLINUX_SYMBOL(__proc_info_end) = .;
+ 
+ #define HYPERVISOR_TEXT							\
+@@ -28,11 +28,11 @@
+ #define IDMAP_TEXT							\
+ 	ALIGN_FUNCTION();						\
+ 	VMLINUX_SYMBOL(__idmap_text_start) = .;				\
+-	*(.idmap.text)							\
++	KEEP(*(.idmap.text))						\
+ 	VMLINUX_SYMBOL(__idmap_text_end) = .;				\
+ 	. = ALIGN(PAGE_SIZE);						\
+ 	VMLINUX_SYMBOL(__hyp_idmap_text_start) = .;			\
+-	*(.hyp.idmap.text)						\
++	KEEP(*(.hyp.idmap.text))					\
+ 	VMLINUX_SYMBOL(__hyp_idmap_text_end) = .;
+ 
+ #ifdef CONFIG_HOTPLUG_CPU
+@@ -105,7 +105,7 @@ SECTIONS
+ 		_stext = .;		/* Text and read-only data	*/
+ 			IDMAP_TEXT
+ 			__exception_text_start = .;
+-			*(.exception.text)
++			KEEP(*(.exception.text))
+ 			__exception_text_end = .;
+ 			IRQENTRY_TEXT
+ 			SOFTIRQENTRY_TEXT
+@@ -134,7 +134,7 @@ SECTIONS
+ 	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
+ 		__start___ex_table = .;
+ #ifdef CONFIG_MMU
+-		*(__ex_table)
++		KEEP(*(__ex_table))
+ #endif
+ 		__stop___ex_table = .;
+ 	}
+@@ -146,12 +146,12 @@ SECTIONS
+ 	. = ALIGN(8);
+ 	.ARM.unwind_idx : {
+ 		__start_unwind_idx = .;
+-		*(.ARM.exidx*)
++		KEEP(*(.ARM.exidx*))
+ 		__stop_unwind_idx = .;
+ 	}
+ 	.ARM.unwind_tab : {
+ 		__start_unwind_tab = .;
+-		*(.ARM.extab*)
++		KEEP(*(.ARM.extab*))
+ 		__stop_unwind_tab = .;
+ 	}
+ #endif
+@@ -171,14 +171,14 @@ SECTIONS
+ 	 */
+ 	__vectors_start = .;
+ 	.vectors 0xffff0000 : AT(__vectors_start) {
+-		*(.vectors)
++		KEEP(*(.vectors))
+ 	}
+ 	. = __vectors_start + SIZEOF(.vectors);
+ 	__vectors_end = .;
+ 
+ 	__stubs_start = .;
+ 	.stubs ADDR(.vectors) + 0x1000 : AT(__stubs_start) {
+-		*(.stubs)
++		KEEP(*(.stubs))
+ 	}
+ 	. = __stubs_start + SIZEOF(.stubs);
+ 	__stubs_end = .;
+@@ -194,24 +194,24 @@ SECTIONS
+ 	}
+ 	.init.arch.info : {
+ 		__arch_info_begin = .;
+-		*(.arch.info.init)
++		KEEP(*(.arch.info.init))
+ 		__arch_info_end = .;
+ 	}
+ 	.init.tagtable : {
+ 		__tagtable_begin = .;
+-		*(.taglist.init)
++		KEEP(*(.taglist.init))
+ 		__tagtable_end = .;
+ 	}
+ #ifdef CONFIG_SMP_ON_UP
+ 	.init.smpalt : {
+ 		__smpalt_begin = .;
+-		*(.alt.smp.init)
++		KEEP(*(.alt.smp.init))
+ 		__smpalt_end = .;
+ 	}
+ #endif
+ 	.init.pv_table : {
+ 		__pv_table_begin = .;
+-		*(.pv_table)
++		KEEP(*(.pv_table))
+ 		__pv_table_end = .;
+ 	}
+ 	.init.data : {
+--- a/arch/arm/boot/compressed/Makefile
++++ b/arch/arm/boot/compressed/Makefile
+@@ -102,6 +102,7 @@ ifeq ($(CONFIG_FUNCTION_TRACER),y)
+ ORIG_CFLAGS := $(KBUILD_CFLAGS)
+ KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
+ endif
++KBUILD_CFLAGS_KERNEL := $(patsubst -f%-sections,,$(KBUILD_CFLAGS_KERNEL))
+ 
+ # -fstack-protector-strong triggers protection checks in this code,
+ # but it is being used too early to link to meaningful stack_chk logic.
+--- a/arch/arm/Kconfig
++++ b/arch/arm/Kconfig
+@@ -81,6 +81,7 @@ config ARM
+ 	select HAVE_UID16
+ 	select HAVE_VIRT_CPU_ACCOUNTING_GEN
+ 	select IRQ_FORCED_THREADING
++	select LD_DEAD_CODE_DATA_ELIMINATION
+ 	select MODULES_USE_ELF_REL
+ 	select NO_BOOTMEM
+ 	select OF_EARLY_FLATTREE if OF
+--- a/arch/mips/Kconfig
++++ b/arch/mips/Kconfig
+@@ -55,6 +55,7 @@ config MIPS
+ 	select CLONE_BACKWARDS
+ 	select HAVE_DEBUG_STACKOVERFLOW
+ 	select HAVE_CC_STACKPROTECTOR
++	select LD_DEAD_CODE_DATA_ELIMINATION
+ 	select CPU_PM if CPU_IDLE
+ 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
+ 	select ARCH_BINFMT_ELF_STATE
+--- a/Makefile
++++ b/Makefile
+@@ -409,6 +409,11 @@ KBUILD_AFLAGS_MODULE  := -DMODULE
+ KBUILD_CFLAGS_MODULE  := -DMODULE
+ KBUILD_LDFLAGS_MODULE = -T $(srctree)/scripts/module-common.lds $(if $(CONFIG_PROFILING),,-s)
+ 
++ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
++KBUILD_CFLAGS_KERNEL	+= $(call cc-option,-ffunction-sections,)
++KBUILD_CFLAGS_KERNEL	+= $(call cc-option,-fdata-sections,)
++endif
++
+ # Read KERNELRELEASE from include/config/kernel.release (if it exists)
+ KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
+ KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
+@@ -630,11 +635,6 @@ include arch/$(SRCARCH)/Makefile
+ KBUILD_CFLAGS	+= $(call cc-option,-fno-delete-null-pointer-checks,)
+ KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
+ 
+-ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
+-KBUILD_CFLAGS	+= $(call cc-option,-ffunction-sections,)
+-KBUILD_CFLAGS	+= $(call cc-option,-fdata-sections,)
+-endif
+-
+ ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
+ KBUILD_CFLAGS	+= -Os $(call cc-disable-warning,maybe-uninitialized,) $(EXTRA_OPTIMIZATION)
+ else