kernel: copy kernel 4.19 code to 5.4

No changes were done to the patches while coping them. Currently they do
not apply on top of kernel 5.4.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 192 insertions, 0 deletions

diff --git a/target/linux/generic/hack-5.4/220-gc_sections.patch b/target/linux/generic/hack-5.4/220-gc_sections.patch
new file mode 100644
index 0000000000..77422e821b
--- /dev/null
+++ b/target/linux/generic/hack-5.4/220-gc_sections.patch
@@ -0,0 +1,192 @@
+From e3d8676f5722b7622685581e06e8f53e6138e3ab Mon Sep 17 00:00:00 2001
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sat, 15 Jul 2017 23:42:36 +0200
+Subject: 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>
+---
+ Makefile                          | 10 +++----
+ arch/arm/Kconfig                  |  1 +
+ arch/arm/boot/compressed/Makefile |  1 +
+ arch/arm/kernel/vmlinux.lds.S     | 26 ++++++++--------
+ arch/mips/Kconfig                 |  1 +
+ arch/mips/kernel/vmlinux.lds.S    |  4 +--
+ include/asm-generic/vmlinux.lds.h | 63 ++++++++++++++++++++-------------------
+ 7 files changed, 55 insertions(+), 51 deletions(-)
+
+--- a/Makefile
++++ b/Makefile
+@@ -294,6 +294,11 @@ else
+ scripts/Kbuild.include: ;
+ include scripts/Kbuild.include
+ 
++ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
++KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
++LDFLAGS_vmlinux += --gc-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)
+@@ -782,11 +787,6 @@ ifdef CONFIG_DEBUG_SECTION_MISMATCH
+ KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once)
+ endif
+ 
+-ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
+-KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
+-LDFLAGS_vmlinux += --gc-sections
+-endif
+-
+ # arch Makefile may override CC so keep this after arch Makefile is included
+ NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
+ 
+--- a/arch/arm/Kconfig
++++ b/arch/arm/Kconfig
+@@ -98,6 +98,7 @@ config ARM
+ 	select HAVE_UID16
+ 	select HAVE_VIRT_CPU_ACCOUNTING_GEN
+ 	select IRQ_FORCED_THREADING
++	select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
+ 	select MODULES_USE_ELF_REL
+ 	select NEED_DMA_MAP_STATE
+ 	select NO_BOOTMEM
+--- a/arch/arm/boot/compressed/Makefile
++++ b/arch/arm/boot/compressed/Makefile
+@@ -106,6 +106,7 @@ ifeq ($(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/kernel/vmlinux.lds.S
++++ b/arch/arm/kernel/vmlinux.lds.S
+@@ -100,24 +100,24 @@ 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 = .;
+ 	}
+ 
+--- a/arch/arm/kernel/vmlinux.lds.h
++++ b/arch/arm/kernel/vmlinux.lds.h
+@@ -22,13 +22,13 @@
+ #define ARM_MMU_DISCARD(x)
+ #else
+ #define ARM_MMU_KEEP(x)
+-#define ARM_MMU_DISCARD(x)	x
++#define ARM_MMU_DISCARD(x)	KEEP(x)
+ #endif
+ 
+ #define PROC_INFO							\
+ 		. = ALIGN(4);						\
+ 		__proc_info_begin = .;					\
+-		*(.proc.info.init)					\
++		KEEP(*(.proc.info.init))				\
+ 		__proc_info_end = .;
+ 
+ #define HYPERVISOR_TEXT							\
+@@ -39,11 +39,11 @@
+ #define IDMAP_TEXT							\
+ 		ALIGN_FUNCTION();					\
+ 		__idmap_text_start = .;					\
+-		*(.idmap.text)						\
++		KEEP(*(.idmap.text))					\
+ 		__idmap_text_end = .;					\
+ 		. = ALIGN(PAGE_SIZE);					\
+ 		__hyp_idmap_text_start = .;				\
+-		*(.hyp.idmap.text)					\
++		KEEP(*(.hyp.idmap.text))				\
+ 		__hyp_idmap_text_end = .;
+ 
+ #define ARM_DISCARD							\
+@@ -86,12 +86,12 @@
+ 	. = 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 = .;					\
+ 	}
+ 
+@@ -102,14 +102,14 @@
+ #define ARM_VECTORS							\
+ 	__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 = .;						\
+--- a/arch/mips/Kconfig
++++ b/arch/mips/Kconfig
+@@ -43,6 +43,7 @@ config MIPS
+ 	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if CPU_SUPPORTS_HUGEPAGES && 64BIT
+ 	select HAVE_CBPF_JIT if (!64BIT && !CPU_MICROMIPS)
+ 	select HAVE_EBPF_JIT if (64BIT && !CPU_MICROMIPS)
++	select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
+ 	select HAVE_CONTEXT_TRACKING
+ 	select HAVE_COPY_THREAD_TLS
+ 	select HAVE_C_RECORDMCOUNT
+--- a/arch/mips/kernel/vmlinux.lds.S
++++ b/arch/mips/kernel/vmlinux.lds.S
+@@ -72,7 +72,7 @@ SECTIONS
+ 	/* Exception table for data bus errors */
+ 	__dbe_table : {
+ 		__start___dbe_table = .;
+-		*(__dbe_table)
++		KEEP(*(__dbe_table))
+ 		__stop___dbe_table = .;
+ 	}
+ 
+@@ -123,7 +123,7 @@ 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 = .;
+ 	}
+