MIPS: Cleanup and Fixup of compressed kernel support

o Remove the .initrd section.  The initrd section was already handled
   when vmlinux was linked.
 o Discard .MIPS.options, .options, .pdr, .reginfo, .comment and .note
   sections.  If .MIPS.options is not removed, kernels compiled with gcc
   3.4.6 will not boot.
 o Clean up the file format.
 o Remove several other unneeded sections.

Tested with GCC 3.4.6 and 4.4.1 with and without initrd.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/785/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Wu Zhangjin 2009-12-10 22:55:13 +08:00 committed by Ralf Baechle
parent abbdc3d88a
commit d4d9a553d7
3 changed files with 59 additions and 155 deletions

View File

@ -56,7 +56,7 @@ $(obj)/piggy.o: $(obj)/vmlinux.$(suffix_y) $(obj)/dummy.o
LDFLAGS_vmlinuz := $(LDFLAGS) -Ttext $(VMLINUZ_LOAD_ADDRESS) -T
vmlinuz: $(src)/ld.script $(obj-y) $(obj)/piggy.o
$(call if_changed,ld)
$(Q)$(OBJCOPY) $(OBJCOPYFLAGS) -R .comment -R .stab -R .stabstr -R .initrd -R .sysmap $@
$(Q)$(OBJCOPY) $(OBJCOPYFLAGS) $@
#
# Some DECstations need all possible sections of an ECOFF executable
@ -84,14 +84,11 @@ vmlinuz.ecoff: $(obj)/../elf2ecoff $(VMLINUZ)
$(obj)/../elf2ecoff: $(src)/../elf2ecoff.c
$(Q)$(HOSTCC) -o $@ $^
drop-sections = .reginfo .mdebug .comment .note .pdr .options .MIPS.options
strip-flags = $(addprefix --remove-section=,$(drop-sections))
OBJCOPYFLAGS_vmlinuz.bin := $(OBJCOPYFLAGS) -O binary $(strip-flags)
OBJCOPYFLAGS_vmlinuz.bin := $(OBJCOPYFLAGS) -O binary
vmlinuz.bin: vmlinuz
$(call if_changed,objcopy)
OBJCOPYFLAGS_vmlinuz.srec := $(OBJCOPYFLAGS) -S -O srec $(strip-flags)
OBJCOPYFLAGS_vmlinuz.srec := $(OBJCOPYFLAGS) -S -O srec
vmlinuz.srec: vmlinuz
$(call if_changed,objcopy)

View File

@ -28,8 +28,6 @@ char *zimage_start;
/* The linker tells us where the image is. */
extern unsigned char __image_begin, __image_end;
extern unsigned char __ramdisk_begin, __ramdisk_end;
unsigned long initrd_size;
/* debug interfaces */
extern void puts(const char *s);
@ -102,14 +100,6 @@ void decompress_kernel(unsigned long boot_heap_start)
puthex((unsigned long)(zimage_size + zimage_start));
puts("\n");
if (initrd_size) {
puts("initrd at: ");
puthex((unsigned long)(&__ramdisk_begin));
puts(" ");
puthex((unsigned long)(&__ramdisk_end));
puts("\n");
}
/* this area are prepared for mallocing when decompressing */
free_mem_ptr = boot_heap_start;
free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;

View File

@ -1,150 +1,67 @@
/*
* ld.script for compressed kernel support of MIPS
*
* Copyright (C) 2009 Lemote Inc.
* Author: Wu Zhangjin <wuzj@lemote.com>
*/
OUTPUT_ARCH(mips)
ENTRY(start)
SECTIONS
{
/* Read-only sections, merged into text segment: */
.init : { *(.init) } =0
.text :
{
_ftext = . ;
*(.text)
*(.rodata)
*(.rodata1)
/* .gnu.warning sections are handled specially by elf32.em. */
*(.gnu.warning)
} =0
.kstrtab : { *(.kstrtab) }
/* . = VMLINUZ_LOAD_ADDRESS */
/* read-only */
_text = .; /* Text and read-only data */
.text : {
_ftext = . ;
*(.text)
*(.rodata)
} = 0
_etext = .; /* End of text section */
. = ALIGN(16); /* Exception table */
__start___ex_table = .;
__ex_table : { *(__ex_table) }
__stop___ex_table = .;
/* writable */
.data : { /* Data */
_fdata = . ;
*(.data)
/* Put the compressed image here, so bss is on the end. */
__image_begin = .;
*(.image)
__image_end = .;
CONSTRUCTORS
}
.sdata : { *(.sdata) }
. = ALIGN(4);
_edata = .; /* End of data section */
__start___dbe_table = .; /* Exception table for data bus errors */
__dbe_table : { *(__dbe_table) }
__stop___dbe_table = .;
/* BSS */
__bss_start = .;
_fbss = .;
.sbss : { *(.sbss) *(.scommon) }
.bss : {
*(.dynbss)
*(.bss)
*(COMMON)
}
. = ALIGN(4);
_end = . ;
__start___ksymtab = .; /* Kernel symbol table */
__ksymtab : { *(__ksymtab) }
__stop___ksymtab = .;
/* These are needed for ELF backends which have not yet been converted
* to the new style linker. */
_etext = .;
.stab 0 : { *(.stab) }
.stabstr 0 : { *(.stabstr) }
. = ALIGN(8192);
.data.init_task : { *(.data.init_task) }
/* These must appear regardless of . */
.gptab.sdata : { *(.gptab.data) *(.gptab.sdata) }
.gptab.sbss : { *(.gptab.bss) *(.gptab.sbss) }
/* Startup code */
. = ALIGN(4096);
__init_begin = .;
.text.init : { *(.text.init) }
.data.init : { *(.data.init) }
. = ALIGN(16);
__setup_start = .;
.setup.init : { *(.setup.init) }
__setup_end = .;
__initcall_start = .;
.initcall.init : { *(.initcall.init) }
__initcall_end = .;
. = ALIGN(4096); /* Align double page for init_task_union */
__init_end = .;
. = ALIGN(4096);
.data.page_aligned : { *(.data.idt) }
. = ALIGN(32);
.data.cacheline_aligned : { *(.data.cacheline_aligned) }
.fini : { *(.fini) } =0
.reginfo : { *(.reginfo) }
/* Adjust the address for the data segment. We want to adjust up to
the same address within the page on the next page up. It would
be more correct to do this:
. = .;
The current expression does not correctly handle the case of a
text segment ending precisely at the end of a page; it causes the
data segment to skip a page. The above expression does not have
this problem, but it will currently (2/95) cause BFD to allocate
a single segment, combining both text and data, for this case.
This will prevent the text segment from being shared among
multiple executions of the program; I think that is more
important than losing a page of the virtual address space (note
that no actual memory is lost; the page which is skipped can not
be referenced). */
. = .;
.data :
{
_fdata = . ;
*(.data)
/* Put the compressed image here, so bss is on the end. */
__image_begin = .;
*(.image)
__image_end = .;
/* Align the initial ramdisk image (INITRD) on page boundaries. */
. = ALIGN(4096);
__ramdisk_begin = .;
*(.initrd)
__ramdisk_end = .;
. = ALIGN(4096);
CONSTRUCTORS
}
.data1 : { *(.data1) }
_gp = . + 0x8000;
.lit8 : { *(.lit8) }
.lit4 : { *(.lit4) }
.ctors : { *(.ctors) }
.dtors : { *(.dtors) }
.got : { *(.got.plt) *(.got) }
.dynamic : { *(.dynamic) }
/* We want the small data sections together, so single-instruction offsets
can access them all, and initialized data all before uninitialized, so
we can shorten the on-disk segment size. */
.sdata : { *(.sdata) }
. = ALIGN(4);
_edata = .;
PROVIDE (edata = .);
__bss_start = .;
_fbss = .;
.sbss : { *(.sbss) *(.scommon) }
.bss :
{
*(.dynbss)
*(.bss)
*(COMMON)
. = ALIGN(4);
_end = . ;
PROVIDE (end = .);
}
/* Sections to be discarded */
/DISCARD/ :
{
*(.text.exit)
*(.data.exit)
*(.exitcall.exit)
}
/* This is the MIPS specific mdebug section. */
.mdebug : { *(.mdebug) }
/* These are needed for ELF backends which have not yet been
converted to the new style linker. */
.stab 0 : { *(.stab) }
.stabstr 0 : { *(.stabstr) }
/* DWARF debug sections.
Symbols in the .debug DWARF section are relative to the beginning of the
section so we begin .debug at 0. It's not clear yet what needs to happen
for the others. */
.debug 0 : { *(.debug) }
.debug_srcinfo 0 : { *(.debug_srcinfo) }
.debug_aranges 0 : { *(.debug_aranges) }
.debug_pubnames 0 : { *(.debug_pubnames) }
.debug_sfnames 0 : { *(.debug_sfnames) }
.line 0 : { *(.line) }
/* These must appear regardless of . */
.gptab.sdata : { *(.gptab.data) *(.gptab.sdata) }
.gptab.sbss : { *(.gptab.bss) *(.gptab.sbss) }
.comment : { *(.comment) }
.note : { *(.note) }
/* Sections to be discarded */
/DISCARD/ : {
*(.MIPS.options)
*(.options)
*(.pdr)
*(.reginfo)
*(.comment)
*(.note)
}
}