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			532 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			532 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
| From: Felix Fietkau <nbd@openwrt.org>
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| 
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| use -ffunction-sections, -fdata-sections and --gc-sections --sort-section=name
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| 
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| In combination with kernel symbol export stripping this significantly reduces
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| the kernel image size. Used on both ARM and MIPS architectures.
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| 
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| Signed-off-by: Felix Fietkau <nbd@openwrt.org>
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| Signed-off-by: Jonas Gorski <jogo@openwrt.org>
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| Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
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| ---
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| 
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| --- a/arch/mips/Makefile
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| +++ b/arch/mips/Makefile
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| @@ -89,10 +89,14 @@ all-$(CONFIG_SYS_SUPPORTS_ZBOOT)+= vmlin
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|  #
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|  cflags-y			+= -G 0 -mno-abicalls -fno-pic -pipe
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|  cflags-y			+= -msoft-float
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| -LDFLAGS_vmlinux			+= -G 0 -static -n -nostdlib
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| +LDFLAGS_vmlinux			+= -G 0 -static -n -nostdlib --gc-sections --sort-section=name
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|  KBUILD_AFLAGS_MODULE		+= -mlong-calls
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|  KBUILD_CFLAGS_MODULE		+= -mlong-calls
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|  
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| +ifndef CONFIG_FUNCTION_TRACER
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| +KBUILD_CFLAGS_KERNEL		+= -ffunction-sections -fdata-sections
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| +endif
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| +
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|  cflags-y += -ffreestanding
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|  
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|  #
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| --- a/arch/mips/kernel/vmlinux.lds.S
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| +++ b/arch/mips/kernel/vmlinux.lds.S
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| @@ -67,7 +67,7 @@ SECTIONS
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|  	/* Exception table for data bus errors */
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|  	__dbe_table : {
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|  		__start___dbe_table = .;
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| -		*(__dbe_table)
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| +		KEEP(*(__dbe_table))
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|  		__stop___dbe_table = .;
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|  	}
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|  
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| @@ -112,7 +112,7 @@ SECTIONS
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|  	. = ALIGN(4);
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|  	.mips.machines.init : AT(ADDR(.mips.machines.init) - LOAD_OFFSET) {
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|  		__mips_machines_start = .;
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| -		*(.mips.machines.init)
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| +		KEEP(*(.mips.machines.init))
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|  		__mips_machines_end = .;
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|  	}
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|  
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| --- a/include/asm-generic/vmlinux.lds.h
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| +++ b/include/asm-generic/vmlinux.lds.h
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| @@ -87,7 +87,7 @@
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|  #ifdef CONFIG_FTRACE_MCOUNT_RECORD
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|  #define MCOUNT_REC()	. = ALIGN(8);				\
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|  			VMLINUX_SYMBOL(__start_mcount_loc) = .; \
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| -			*(__mcount_loc)				\
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| +			KEEP(*(__mcount_loc))			\
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|  			VMLINUX_SYMBOL(__stop_mcount_loc) = .;
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|  #else
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|  #define MCOUNT_REC()
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| @@ -95,7 +95,7 @@
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|  
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|  #ifdef CONFIG_TRACE_BRANCH_PROFILING
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|  #define LIKELY_PROFILE()	VMLINUX_SYMBOL(__start_annotated_branch_profile) = .; \
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| -				*(_ftrace_annotated_branch)			      \
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| +				KEEP(*(_ftrace_annotated_branch))		      \
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|  				VMLINUX_SYMBOL(__stop_annotated_branch_profile) = .;
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|  #else
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|  #define LIKELY_PROFILE()
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| @@ -103,7 +103,7 @@
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|  
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|  #ifdef CONFIG_PROFILE_ALL_BRANCHES
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|  #define BRANCH_PROFILE()	VMLINUX_SYMBOL(__start_branch_profile) = .;   \
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| -				*(_ftrace_branch)			      \
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| +				KEEP(*(_ftrace_branch))			      \
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|  				VMLINUX_SYMBOL(__stop_branch_profile) = .;
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|  #else
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|  #define BRANCH_PROFILE()
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| @@ -112,7 +112,7 @@
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|  #ifdef CONFIG_EVENT_TRACING
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|  #define FTRACE_EVENTS()	. = ALIGN(8);					\
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|  			VMLINUX_SYMBOL(__start_ftrace_events) = .;	\
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| -			*(_ftrace_events)				\
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| +			KEEP(*(_ftrace_events))				\
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|  			VMLINUX_SYMBOL(__stop_ftrace_events) = .;
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|  #else
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|  #define FTRACE_EVENTS()
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| @@ -120,7 +120,7 @@
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|  
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|  #ifdef CONFIG_TRACING
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|  #define TRACE_PRINTKS() VMLINUX_SYMBOL(__start___trace_bprintk_fmt) = .;      \
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| -			 *(__trace_printk_fmt) /* Trace_printk fmt' pointer */ \
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| +			 KEEP(*(__trace_printk_fmt)) /* Trace_printk fmt' pointer */ \
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|  			 VMLINUX_SYMBOL(__stop___trace_bprintk_fmt) = .;
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|  #define TRACEPOINT_STR() VMLINUX_SYMBOL(__start___tracepoint_str) = .;	\
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|  			 *(__tracepoint_str) /* Trace_printk fmt' pointer */ \
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| @@ -133,7 +133,7 @@
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|  #ifdef CONFIG_FTRACE_SYSCALLS
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|  #define TRACE_SYSCALLS() . = ALIGN(8);					\
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|  			 VMLINUX_SYMBOL(__start_syscalls_metadata) = .;	\
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| -			 *(__syscalls_metadata)				\
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| +			 KEEP(*(__syscalls_metadata))			\
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|  			 VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
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|  #else
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|  #define TRACE_SYSCALLS()
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| @@ -142,8 +142,8 @@
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|  #ifdef CONFIG_CLKSRC_OF
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|  #define CLKSRC_OF_TABLES() . = ALIGN(8);				\
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|  			   VMLINUX_SYMBOL(__clksrc_of_table) = .;	\
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| -			   *(__clksrc_of_table)				\
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| -			   *(__clksrc_of_table_end)
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| +			   KEEP(*(__clksrc_of_table))			\
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| +			   KEEP(*(__clksrc_of_table_end))
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|  #else
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|  #define CLKSRC_OF_TABLES()
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|  #endif
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| @@ -152,8 +152,8 @@
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|  #define IRQCHIP_OF_MATCH_TABLE()					\
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|  	. = ALIGN(8);							\
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|  	VMLINUX_SYMBOL(__irqchip_begin) = .;				\
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| -	*(__irqchip_of_table)		  				\
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| -	*(__irqchip_of_end)
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| +	KEEP(*(__irqchip_of_table))	  				\
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| +	KEEP(*(__irqchip_of_end))
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|  #else
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|  #define IRQCHIP_OF_MATCH_TABLE()
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|  #endif
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| @@ -161,8 +161,8 @@
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|  #ifdef CONFIG_COMMON_CLK
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|  #define CLK_OF_TABLES() . = ALIGN(8);				\
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|  			VMLINUX_SYMBOL(__clk_of_table) = .;	\
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| -			*(__clk_of_table)			\
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| -			*(__clk_of_table_end)
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| +			KEEP(*(__clk_of_table))			\
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| +			KEEP(*(__clk_of_table_end))
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|  #else
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|  #define CLK_OF_TABLES()
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|  #endif
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| @@ -170,7 +170,7 @@
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|  #define KERNEL_DTB()							\
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|  	STRUCT_ALIGN();							\
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|  	VMLINUX_SYMBOL(__dtb_start) = .;				\
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| -	*(.dtb.init.rodata)						\
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| +	KEEP(*(.dtb.init.rodata))					\
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|  	VMLINUX_SYMBOL(__dtb_end) = .;
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|  
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|  /* .data section */
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| @@ -186,16 +186,17 @@
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|  	/* implement dynamic printk debug */				\
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|  	. = ALIGN(8);                                                   \
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|  	VMLINUX_SYMBOL(__start___jump_table) = .;                       \
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| -	*(__jump_table)                                                 \
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| +	KEEP(*(__jump_table))                                           \
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|  	VMLINUX_SYMBOL(__stop___jump_table) = .;                        \
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|  	. = ALIGN(8);							\
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|  	VMLINUX_SYMBOL(__start___verbose) = .;                          \
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| -	*(__verbose)                                                    \
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| +	KEEP(*(__verbose))                                              \
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|  	VMLINUX_SYMBOL(__stop___verbose) = .;				\
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|  	LIKELY_PROFILE()		       				\
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|  	BRANCH_PROFILE()						\
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|  	TRACE_PRINTKS()							\
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| -	TRACEPOINT_STR()
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| +	TRACEPOINT_STR()                                                \
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| +	*(.data.[a-zA-Z_]*)
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|  
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|  /*
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|   * Data section helpers
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| @@ -249,32 +250,32 @@
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|  	/* PCI quirks */						\
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|  	.pci_fixup        : AT(ADDR(.pci_fixup) - LOAD_OFFSET) {	\
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|  		VMLINUX_SYMBOL(__start_pci_fixups_early) = .;		\
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| -		*(.pci_fixup_early)					\
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| +		KEEP(*(.pci_fixup_early))				\
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|  		VMLINUX_SYMBOL(__end_pci_fixups_early) = .;		\
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|  		VMLINUX_SYMBOL(__start_pci_fixups_header) = .;		\
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| -		*(.pci_fixup_header)					\
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| +		KEEP(*(.pci_fixup_header))				\
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|  		VMLINUX_SYMBOL(__end_pci_fixups_header) = .;		\
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|  		VMLINUX_SYMBOL(__start_pci_fixups_final) = .;		\
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| -		*(.pci_fixup_final)					\
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| +		KEEP(*(.pci_fixup_final))				\
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|  		VMLINUX_SYMBOL(__end_pci_fixups_final) = .;		\
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|  		VMLINUX_SYMBOL(__start_pci_fixups_enable) = .;		\
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| -		*(.pci_fixup_enable)					\
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| +		KEEP(*(.pci_fixup_enable))				\
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|  		VMLINUX_SYMBOL(__end_pci_fixups_enable) = .;		\
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|  		VMLINUX_SYMBOL(__start_pci_fixups_resume) = .;		\
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| -		*(.pci_fixup_resume)					\
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| +		KEEP(*(.pci_fixup_resume))				\
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|  		VMLINUX_SYMBOL(__end_pci_fixups_resume) = .;		\
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|  		VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .;	\
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| -		*(.pci_fixup_resume_early)				\
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| +		KEEP(*(.pci_fixup_resume_early))			\
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|  		VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .;	\
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|  		VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .;		\
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| -		*(.pci_fixup_suspend)					\
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| +		KEEP(*(.pci_fixup_suspend))				\
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|  		VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .;		\
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|  	}								\
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|  									\
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|  	/* Built-in firmware blobs */					\
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|  	.builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {	\
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|  		VMLINUX_SYMBOL(__start_builtin_fw) = .;			\
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| -		*(.builtin_fw)						\
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| +		KEEP(*(.builtin_fw))					\
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|  		VMLINUX_SYMBOL(__end_builtin_fw) = .;			\
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|  	}								\
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|  									\
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| @@ -283,49 +284,49 @@
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|  	/* Kernel symbol table: Normal symbols */			\
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|  	__ksymtab         : AT(ADDR(__ksymtab) - LOAD_OFFSET) {		\
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|  		VMLINUX_SYMBOL(__start___ksymtab) = .;			\
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| -		*(SORT(___ksymtab+*))					\
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| +		KEEP(*(SORT(___ksymtab+*)))				\
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|  		VMLINUX_SYMBOL(__stop___ksymtab) = .;			\
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|  	}								\
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|  									\
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|  	/* Kernel symbol table: GPL-only symbols */			\
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|  	__ksymtab_gpl     : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) {	\
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|  		VMLINUX_SYMBOL(__start___ksymtab_gpl) = .;		\
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| -		*(SORT(___ksymtab_gpl+*))				\
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| +		KEEP(*(SORT(___ksymtab_gpl+*)))				\
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|  		VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .;		\
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|  	}								\
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|  									\
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|  	/* Kernel symbol table: Normal unused symbols */		\
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|  	__ksymtab_unused  : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) {	\
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|  		VMLINUX_SYMBOL(__start___ksymtab_unused) = .;		\
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| -		*(SORT(___ksymtab_unused+*))				\
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| +		KEEP(*(SORT(___ksymtab_unused+*)))			\
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|  		VMLINUX_SYMBOL(__stop___ksymtab_unused) = .;		\
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|  	}								\
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|  									\
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|  	/* Kernel symbol table: GPL-only unused symbols */		\
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|  	__ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
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|  		VMLINUX_SYMBOL(__start___ksymtab_unused_gpl) = .;	\
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| -		*(SORT(___ksymtab_unused_gpl+*))			\
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| +		KEEP(*(SORT(___ksymtab_unused_gpl+*)))			\
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|  		VMLINUX_SYMBOL(__stop___ksymtab_unused_gpl) = .;	\
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|  	}								\
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|  									\
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|  	/* Kernel symbol table: GPL-future-only symbols */		\
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|  	__ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
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|  		VMLINUX_SYMBOL(__start___ksymtab_gpl_future) = .;	\
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| -		*(SORT(___ksymtab_gpl_future+*))			\
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| +		KEEP(*(SORT(___ksymtab_gpl_future+*)))			\
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|  		VMLINUX_SYMBOL(__stop___ksymtab_gpl_future) = .;	\
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|  	}								\
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|  									\
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|  	/* Kernel symbol table: Normal symbols */			\
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|  	__kcrctab         : AT(ADDR(__kcrctab) - LOAD_OFFSET) {		\
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|  		VMLINUX_SYMBOL(__start___kcrctab) = .;			\
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| -		*(SORT(___kcrctab+*))					\
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| +		KEEP(*(SORT(___kcrctab+*)))				\
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|  		VMLINUX_SYMBOL(__stop___kcrctab) = .;			\
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|  	}								\
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|  									\
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|  	/* Kernel symbol table: GPL-only symbols */			\
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|  	__kcrctab_gpl     : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) {	\
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|  		VMLINUX_SYMBOL(__start___kcrctab_gpl) = .;		\
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| -		*(SORT(___kcrctab_gpl+*))				\
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| +		KEEP(*(SORT(___kcrctab_gpl+*)))				\
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|  		VMLINUX_SYMBOL(__stop___kcrctab_gpl) = .;		\
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|  	}								\
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|  									\
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| @@ -339,14 +340,14 @@
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|  	/* Kernel symbol table: GPL-only unused symbols */		\
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|  	__kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
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|  		VMLINUX_SYMBOL(__start___kcrctab_unused_gpl) = .;	\
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| -		*(SORT(___kcrctab_unused_gpl+*))			\
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| +		KEEP(*(SORT(___kcrctab_unused_gpl+*)))			\
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|  		VMLINUX_SYMBOL(__stop___kcrctab_unused_gpl) = .;	\
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|  	}								\
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|  									\
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|  	/* Kernel symbol table: GPL-future-only symbols */		\
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|  	__kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
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|  		VMLINUX_SYMBOL(__start___kcrctab_gpl_future) = .;	\
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| -		*(SORT(___kcrctab_gpl_future+*))			\
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| +		KEEP(*(SORT(___kcrctab_gpl_future+*)))			\
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|  		VMLINUX_SYMBOL(__stop___kcrctab_gpl_future) = .;	\
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|  	}								\
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|  									\
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| @@ -365,14 +366,14 @@
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|  	/* Built-in module parameters. */				\
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|  	__param : AT(ADDR(__param) - LOAD_OFFSET) {			\
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|  		VMLINUX_SYMBOL(__start___param) = .;			\
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| -		*(__param)						\
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| +		KEEP(*(__param))					\
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|  		VMLINUX_SYMBOL(__stop___param) = .;			\
 | |
|  	}								\
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|  									\
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|  	/* Built-in module versions. */					\
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|  	__modver : AT(ADDR(__modver) - LOAD_OFFSET) {			\
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|  		VMLINUX_SYMBOL(__start___modver) = .;			\
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| -		*(__modver)						\
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| +		KEEP(*(__modver))					\
 | |
|  		VMLINUX_SYMBOL(__stop___modver) = .;			\
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|  		. = ALIGN((align));					\
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|  		VMLINUX_SYMBOL(__end_rodata) = .;			\
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| @@ -428,7 +429,7 @@
 | |
|  #define ENTRY_TEXT							\
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|  		ALIGN_FUNCTION();					\
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|  		VMLINUX_SYMBOL(__entry_text_start) = .;			\
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| -		*(.entry.text)						\
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| +		KEEP(*(.entry.text))					\
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|  		VMLINUX_SYMBOL(__entry_text_end) = .;
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|  
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|  #ifdef CONFIG_FUNCTION_GRAPH_TRACER
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| @@ -456,7 +457,7 @@
 | |
|  	. = ALIGN(align);						\
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|  	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {		\
 | |
|  		VMLINUX_SYMBOL(__start___ex_table) = .;			\
 | |
| -		*(__ex_table)						\
 | |
| +		KEEP(*(__ex_table))						\
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|  		VMLINUX_SYMBOL(__stop___ex_table) = .;			\
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|  	}
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|  
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| @@ -472,8 +473,8 @@
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|  #ifdef CONFIG_CONSTRUCTORS
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|  #define KERNEL_CTORS()	. = ALIGN(8);			   \
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|  			VMLINUX_SYMBOL(__ctors_start) = .; \
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| -			*(.ctors)			   \
 | |
| -			*(.init_array)			   \
 | |
| +			KEEP(*(.ctors))			   \
 | |
| +			KEEP(*(.init_array))		   \
 | |
|  			VMLINUX_SYMBOL(__ctors_end) = .;
 | |
|  #else
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|  #define KERNEL_CTORS()
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| @@ -517,7 +518,7 @@
 | |
|  #define SBSS(sbss_align)						\
 | |
|  	. = ALIGN(sbss_align);						\
 | |
|  	.sbss : AT(ADDR(.sbss) - LOAD_OFFSET) {				\
 | |
| -		*(.sbss)						\
 | |
| +		*(.sbss .sbss.*)					\
 | |
|  		*(.scommon)						\
 | |
|  	}
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|  
 | |
| @@ -535,7 +536,7 @@
 | |
|  		BSS_FIRST_SECTIONS					\
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|  		*(.bss..page_aligned)					\
 | |
|  		*(.dynbss)						\
 | |
| -		*(.bss)							\
 | |
| +		*(.bss .bss.*)						\
 | |
|  		*(COMMON)						\
 | |
|  	}
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|  
 | |
| @@ -596,7 +597,7 @@
 | |
|  	. = ALIGN(4);							\
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|  	.tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) {		\
 | |
|  		VMLINUX_SYMBOL(__tracedata_start) = .;			\
 | |
| -		*(.tracedata)						\
 | |
| +		KEEP(*(.tracedata))					\
 | |
|  		VMLINUX_SYMBOL(__tracedata_end) = .;			\
 | |
|  	}
 | |
|  #else
 | |
| @@ -613,17 +614,17 @@
 | |
|  #define INIT_SETUP(initsetup_align)					\
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|  		. = ALIGN(initsetup_align);				\
 | |
|  		VMLINUX_SYMBOL(__setup_start) = .;			\
 | |
| -		*(.init.setup)						\
 | |
| +		KEEP(*(.init.setup))					\
 | |
|  		VMLINUX_SYMBOL(__setup_end) = .;
 | |
|  
 | |
|  #define INIT_CALLS_LEVEL(level)						\
 | |
|  		VMLINUX_SYMBOL(__initcall##level##_start) = .;		\
 | |
| -		*(.initcall##level##.init)				\
 | |
| -		*(.initcall##level##s.init)				\
 | |
| +		KEEP(*(.initcall##level##.init))			\
 | |
| +		KEEP(*(.initcall##level##s.init))			\
 | |
|  
 | |
|  #define INIT_CALLS							\
 | |
|  		VMLINUX_SYMBOL(__initcall_start) = .;			\
 | |
| -		*(.initcallearly.init)					\
 | |
| +		KEEP(*(.initcallearly.init))				\
 | |
|  		INIT_CALLS_LEVEL(0)					\
 | |
|  		INIT_CALLS_LEVEL(1)					\
 | |
|  		INIT_CALLS_LEVEL(2)					\
 | |
| @@ -637,21 +638,21 @@
 | |
|  
 | |
|  #define CON_INITCALL							\
 | |
|  		VMLINUX_SYMBOL(__con_initcall_start) = .;		\
 | |
| -		*(.con_initcall.init)					\
 | |
| +		KEEP(*(.con_initcall.init))				\
 | |
|  		VMLINUX_SYMBOL(__con_initcall_end) = .;
 | |
|  
 | |
|  #define SECURITY_INITCALL						\
 | |
|  		VMLINUX_SYMBOL(__security_initcall_start) = .;		\
 | |
| -		*(.security_initcall.init)				\
 | |
| +		KEEP(*(.security_initcall.init))			\
 | |
|  		VMLINUX_SYMBOL(__security_initcall_end) = .;
 | |
|  
 | |
|  #ifdef CONFIG_BLK_DEV_INITRD
 | |
|  #define INIT_RAM_FS							\
 | |
|  	. = ALIGN(4);							\
 | |
|  	VMLINUX_SYMBOL(__initramfs_start) = .;				\
 | |
| -	*(.init.ramfs)							\
 | |
| +	KEEP(*(.init.ramfs))						\
 | |
|  	. = ALIGN(8);							\
 | |
| -	*(.init.ramfs.info)
 | |
| +	KEEP(*(.init.ramfs.info))
 | |
|  #else
 | |
|  #define INIT_RAM_FS
 | |
|  #endif
 | |
| --- a/arch/arm/Makefile
 | |
| +++ b/arch/arm/Makefile
 | |
| @@ -18,11 +18,16 @@ ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
 | |
|  LDFLAGS_vmlinux	+= --be8
 | |
|  LDFLAGS_MODULE	+= --be8
 | |
|  endif
 | |
| +LDFLAGS_vmlinux += --gc-sections --sort-section=name
 | |
|  
 | |
|  OBJCOPYFLAGS	:=-O binary -R .comment -S
 | |
|  GZFLAGS		:=-9
 | |
|  #KBUILD_CFLAGS	+=-pipe
 | |
|  
 | |
| +ifndef CONFIG_FUNCTION_TRACER
 | |
| +KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
 | |
| +endif
 | |
| +
 | |
|  # Never generate .eh_frame
 | |
|  KBUILD_CFLAGS	+= $(call cc-option,-fno-dwarf2-cfi-asm)
 | |
|  
 | |
| --- a/arch/arm/kernel/vmlinux.lds.S
 | |
| +++ b/arch/arm/kernel/vmlinux.lds.S
 | |
| @@ -12,13 +12,13 @@
 | |
|  #define PROC_INFO							\
 | |
|  	. = ALIGN(4);							\
 | |
|  	VMLINUX_SYMBOL(__proc_info_begin) = .;				\
 | |
| -	*(.proc.info.init)						\
 | |
| +	KEEP(*(.proc.info.init))					\
 | |
|  	VMLINUX_SYMBOL(__proc_info_end) = .;
 | |
|  
 | |
|  #define IDMAP_TEXT							\
 | |
|  	ALIGN_FUNCTION();						\
 | |
|  	VMLINUX_SYMBOL(__idmap_text_start) = .;				\
 | |
| -	*(.idmap.text)							\
 | |
| +	KEEP(*(.idmap.text))						\
 | |
|  	VMLINUX_SYMBOL(__idmap_text_end) = .;				\
 | |
|  	. = ALIGN(32);							\
 | |
|  	VMLINUX_SYMBOL(__hyp_idmap_text_start) = .;			\
 | |
| @@ -93,7 +93,7 @@ SECTIONS
 | |
|  	.text : {			/* Real text segment		*/
 | |
|  		_stext = .;		/* Text and read-only data	*/
 | |
|  			__exception_text_start = .;
 | |
| -			*(.exception.text)
 | |
| +			KEEP(*(.exception.text))
 | |
|  			__exception_text_end = .;
 | |
|  			IRQENTRY_TEXT
 | |
|  			TEXT_TEXT
 | |
| @@ -118,7 +118,7 @@ SECTIONS
 | |
|  	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
 | |
|  		__start___ex_table = .;
 | |
|  #ifdef CONFIG_MMU
 | |
| -		*(__ex_table)
 | |
| +		KEEP(*(__ex_table))
 | |
|  #endif
 | |
|  		__stop___ex_table = .;
 | |
|  	}
 | |
| @@ -130,12 +130,12 @@ 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
 | |
| @@ -154,14 +154,14 @@ SECTIONS
 | |
|  	 */
 | |
|  	__vectors_start = .;
 | |
|  	.vectors 0 : AT(__vectors_start) {
 | |
| -		*(.vectors)
 | |
| +		KEEP(*(.vectors))
 | |
|  	}
 | |
|  	. = __vectors_start + SIZEOF(.vectors);
 | |
|  	__vectors_end = .;
 | |
|  
 | |
|  	__stubs_start = .;
 | |
|  	.stubs 0x1000 : AT(__stubs_start) {
 | |
| -		*(.stubs)
 | |
| +		KEEP(*(.stubs))
 | |
|  	}
 | |
|  	. = __stubs_start + SIZEOF(.stubs);
 | |
|  	__stubs_end = .;
 | |
| @@ -175,24 +175,24 @@ 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
 | |
| @@ -120,6 +120,7 @@ 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))
 | |
|  
 | |
|  ccflags-y := -fpic -mno-single-pic-base -fno-builtin -I$(obj)
 | |
|  asflags-y := -DZIMAGE
 |