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2efac77e82
While the recent cset 86384d5441 did improve
things it didn't resolve all the problems. So bite the bullet and discard
.exit.text and .exit.data at runtime. Which of course sucks because it
bloats binaries with code that will never ever be used but it's the only
thing that will work reliable as demonstrated by the function sd_major() in
drivers/scsi/sd.c.
Gcc may compile sd_major() using a jump table which it will put into
.rodata. If it also inlines sd_major's function body into exit_sd() which
gcc > 3.4.x does. If CONFIG_BLK_DEV_SD has been set to y we would like ld
to discard exit_sd's code at link time. However sd_major happens to
contain a switch statement which gcc will compile using a jump table in
.rodata on the architectures I checked. So, when ld later discards
.exit.text only the jump table in .rodata with its stale references to
the discard .exit.text will be left which any no antique ld will honor
with a link error.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
167 lines
3.8 KiB
ArmAsm
167 lines
3.8 KiB
ArmAsm
#include <asm/asm-offsets.h>
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#include <asm-generic/vmlinux.lds.h>
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#undef mips
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#define mips mips
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OUTPUT_ARCH(mips)
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ENTRY(kernel_entry)
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jiffies = JIFFIES;
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SECTIONS
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{
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#ifdef CONFIG_BOOT_ELF64
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/* Read-only sections, merged into text segment: */
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/* . = 0xc000000000000000; */
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/* This is the value for an Origin kernel, taken from an IRIX kernel. */
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/* . = 0xc00000000001c000; */
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/* Set the vaddr for the text segment to a value
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>= 0xa800 0000 0001 9000 if no symmon is going to configured
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>= 0xa800 0000 0030 0000 otherwise */
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/* . = 0xa800000000300000; */
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/* . = 0xa800000000300000; */
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. = 0xffffffff80300000;
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#endif
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. = LOADADDR;
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/* read-only */
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_text = .; /* Text and read-only data */
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.text : {
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*(.text)
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SCHED_TEXT
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LOCK_TEXT
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*(.fixup)
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*(.gnu.warning)
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} =0
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_etext = .; /* End of text section */
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. = ALIGN(16); /* Exception table */
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__start___ex_table = .;
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__ex_table : { *(__ex_table) }
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__stop___ex_table = .;
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__start___dbe_table = .; /* Exception table for data bus errors */
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__dbe_table : { *(__dbe_table) }
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__stop___dbe_table = .;
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RODATA
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/* writeable */
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.data : { /* Data */
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. = . + DATAOFFSET; /* for CONFIG_MAPPED_KERNEL */
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/*
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* This ALIGN is needed as a workaround for a bug a gcc bug upto 4.1 which
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* limits the maximum alignment to at most 32kB and results in the following
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* warning:
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*
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* CC arch/mips/kernel/init_task.o
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* arch/mips/kernel/init_task.c:30: warning: alignment of ‘init_thread_union’
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* is greater than maximum object file alignment. Using 32768
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*/
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. = ALIGN(_PAGE_SIZE);
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*(.data.init_task)
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*(.data)
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CONSTRUCTORS
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}
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_gp = . + 0x8000;
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.lit8 : { *(.lit8) }
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.lit4 : { *(.lit4) }
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/* We want the small data sections together, so single-instruction offsets
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can access them all, and initialized data all before uninitialized, so
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we can shorten the on-disk segment size. */
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.sdata : { *(.sdata) }
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. = ALIGN(_PAGE_SIZE);
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__nosave_begin = .;
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.data_nosave : { *(.data.nosave) }
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. = ALIGN(_PAGE_SIZE);
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__nosave_end = .;
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. = ALIGN(32);
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.data.cacheline_aligned : { *(.data.cacheline_aligned) }
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_edata = .; /* End of data section */
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/* will be freed after init */
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. = ALIGN(_PAGE_SIZE); /* Init code and data */
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__init_begin = .;
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.init.text : {
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_sinittext = .;
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*(.init.text)
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_einittext = .;
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}
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.init.data : { *(.init.data) }
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. = ALIGN(16);
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__setup_start = .;
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.init.setup : { *(.init.setup) }
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__setup_end = .;
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__initcall_start = .;
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.initcall.init : {
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INITCALLS
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}
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__initcall_end = .;
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__con_initcall_start = .;
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.con_initcall.init : { *(.con_initcall.init) }
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__con_initcall_end = .;
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SECURITY_INIT
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/* .exit.text is discarded at runtime, not link time, to deal with
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references from .rodata */
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.exit.text : { *(.exit.text) }
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.exit.data : { *(.exit.data) }
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. = ALIGN(_PAGE_SIZE);
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__initramfs_start = .;
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.init.ramfs : { *(.init.ramfs) }
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__initramfs_end = .;
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. = ALIGN(32);
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__per_cpu_start = .;
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.data.percpu : { *(.data.percpu) }
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__per_cpu_end = .;
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. = ALIGN(_PAGE_SIZE);
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__init_end = .;
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/* freed after init ends here */
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__bss_start = .; /* BSS */
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.sbss : {
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*(.sbss)
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*(.scommon)
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}
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.bss : {
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*(.bss)
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*(COMMON)
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}
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__bss_stop = .;
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_end = . ;
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/* Sections to be discarded */
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/DISCARD/ : {
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*(.exitcall.exit)
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/* ABI crap starts here */
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*(.comment)
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*(.MIPS.options)
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*(.note)
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*(.options)
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*(.pdr)
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*(.reginfo)
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*(.mdebug*)
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}
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/* This is the MIPS specific mdebug section. */
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.mdebug : { *(.mdebug) }
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STABS_DEBUG
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DWARF_DEBUG
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/* These must appear regardless of . */
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.gptab.sdata : { *(.gptab.data) *(.gptab.sdata) }
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.gptab.sbss : { *(.gptab.bss) *(.gptab.sbss) }
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.note : { *(.note) }
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}
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