mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-28 07:04:00 +08:00
98ededb61f
Boris suggests to make a local label (prepend ".L") to these functions to eliminate them from the symbol table. These are functions with very local names and really should not be visible anywhere. Note that objtool won't see these functions anymore (to generate ORC debug info). But all the functions are not annotated with ENDPROC, so they won't have objtool's attention anyway. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Cao jin <caoj.fnst@cn.fujitsu.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steve Winslow <swinslow@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Huang <wei@redhat.com> Cc: x86-ml <x86@kernel.org> Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com> Link: https://lkml.kernel.org/r/20190906075550.23435-2-jslaby@suse.cz
283 lines
6.1 KiB
ArmAsm
283 lines
6.1 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* linux/boot/head.S
|
|
*
|
|
* Copyright (C) 1991, 1992, 1993 Linus Torvalds
|
|
*/
|
|
|
|
/*
|
|
* head.S contains the 32-bit startup code.
|
|
*
|
|
* NOTE!!! Startup happens at absolute address 0x00001000, which is also where
|
|
* the page directory will exist. The startup code will be overwritten by
|
|
* the page directory. [According to comments etc elsewhere on a compressed
|
|
* kernel it will end up at 0x1000 + 1Mb I hope so as I assume this. - AC]
|
|
*
|
|
* Page 0 is deliberately kept safe, since System Management Mode code in
|
|
* laptops may need to access the BIOS data stored there. This is also
|
|
* useful for future device drivers that either access the BIOS via VM86
|
|
* mode.
|
|
*/
|
|
|
|
/*
|
|
* High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
|
|
*/
|
|
.text
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/linkage.h>
|
|
#include <asm/segment.h>
|
|
#include <asm/page_types.h>
|
|
#include <asm/boot.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/bootparam.h>
|
|
|
|
/*
|
|
* The 32-bit x86 assembler in binutils 2.26 will generate R_386_GOT32X
|
|
* relocation to get the symbol address in PIC. When the compressed x86
|
|
* kernel isn't built as PIC, the linker optimizes R_386_GOT32X
|
|
* relocations to their fixed symbol addresses. However, when the
|
|
* compressed x86 kernel is loaded at a different address, it leads
|
|
* to the following load failure:
|
|
*
|
|
* Failed to allocate space for phdrs
|
|
*
|
|
* during the decompression stage.
|
|
*
|
|
* If the compressed x86 kernel is relocatable at run-time, it should be
|
|
* compiled with -fPIE, instead of -fPIC, if possible and should be built as
|
|
* Position Independent Executable (PIE) so that linker won't optimize
|
|
* R_386_GOT32X relocation to its fixed symbol address. Older
|
|
* linkers generate R_386_32 relocations against locally defined symbols,
|
|
* _bss, _ebss, _got and _egot, in PIE. It isn't wrong, just less
|
|
* optimal than R_386_RELATIVE. But the x86 kernel fails to properly handle
|
|
* R_386_32 relocations when relocating the kernel. To generate
|
|
* R_386_RELATIVE relocations, we mark _bss, _ebss, _got and _egot as
|
|
* hidden:
|
|
*/
|
|
.hidden _bss
|
|
.hidden _ebss
|
|
.hidden _got
|
|
.hidden _egot
|
|
|
|
__HEAD
|
|
ENTRY(startup_32)
|
|
cld
|
|
/*
|
|
* Test KEEP_SEGMENTS flag to see if the bootloader is asking
|
|
* us to not reload segments
|
|
*/
|
|
testb $KEEP_SEGMENTS, BP_loadflags(%esi)
|
|
jnz 1f
|
|
|
|
cli
|
|
movl $__BOOT_DS, %eax
|
|
movl %eax, %ds
|
|
movl %eax, %es
|
|
movl %eax, %fs
|
|
movl %eax, %gs
|
|
movl %eax, %ss
|
|
1:
|
|
|
|
/*
|
|
* Calculate the delta between where we were compiled to run
|
|
* at and where we were actually loaded at. This can only be done
|
|
* with a short local call on x86. Nothing else will tell us what
|
|
* address we are running at. The reserved chunk of the real-mode
|
|
* data at 0x1e4 (defined as a scratch field) are used as the stack
|
|
* for this calculation. Only 4 bytes are needed.
|
|
*/
|
|
leal (BP_scratch+4)(%esi), %esp
|
|
call 1f
|
|
1: popl %ebp
|
|
subl $1b, %ebp
|
|
|
|
/*
|
|
* %ebp contains the address we are loaded at by the boot loader and %ebx
|
|
* contains the address where we should move the kernel image temporarily
|
|
* for safe in-place decompression.
|
|
*/
|
|
|
|
#ifdef CONFIG_RELOCATABLE
|
|
movl %ebp, %ebx
|
|
movl BP_kernel_alignment(%esi), %eax
|
|
decl %eax
|
|
addl %eax, %ebx
|
|
notl %eax
|
|
andl %eax, %ebx
|
|
cmpl $LOAD_PHYSICAL_ADDR, %ebx
|
|
jge 1f
|
|
#endif
|
|
movl $LOAD_PHYSICAL_ADDR, %ebx
|
|
1:
|
|
|
|
/* Target address to relocate to for decompression */
|
|
movl BP_init_size(%esi), %eax
|
|
subl $_end, %eax
|
|
addl %eax, %ebx
|
|
|
|
/* Set up the stack */
|
|
leal boot_stack_end(%ebx), %esp
|
|
|
|
/* Zero EFLAGS */
|
|
pushl $0
|
|
popfl
|
|
|
|
/*
|
|
* Copy the compressed kernel to the end of our buffer
|
|
* where decompression in place becomes safe.
|
|
*/
|
|
pushl %esi
|
|
leal (_bss-4)(%ebp), %esi
|
|
leal (_bss-4)(%ebx), %edi
|
|
movl $(_bss - startup_32), %ecx
|
|
shrl $2, %ecx
|
|
std
|
|
rep movsl
|
|
cld
|
|
popl %esi
|
|
|
|
/*
|
|
* Jump to the relocated address.
|
|
*/
|
|
leal .Lrelocated(%ebx), %eax
|
|
jmp *%eax
|
|
ENDPROC(startup_32)
|
|
|
|
#ifdef CONFIG_EFI_STUB
|
|
/*
|
|
* We don't need the return address, so set up the stack so efi_main() can find
|
|
* its arguments.
|
|
*/
|
|
ENTRY(efi_pe_entry)
|
|
add $0x4, %esp
|
|
|
|
call 1f
|
|
1: popl %esi
|
|
subl $1b, %esi
|
|
|
|
popl %ecx
|
|
movl %ecx, efi32_config(%esi) /* Handle */
|
|
popl %ecx
|
|
movl %ecx, efi32_config+8(%esi) /* EFI System table pointer */
|
|
|
|
/* Relocate efi_config->call() */
|
|
leal efi32_config(%esi), %eax
|
|
add %esi, 40(%eax)
|
|
pushl %eax
|
|
|
|
call make_boot_params
|
|
cmpl $0, %eax
|
|
je fail
|
|
movl %esi, BP_code32_start(%eax)
|
|
popl %ecx
|
|
pushl %eax
|
|
pushl %ecx
|
|
jmp 2f /* Skip efi_config initialization */
|
|
ENDPROC(efi_pe_entry)
|
|
|
|
ENTRY(efi32_stub_entry)
|
|
add $0x4, %esp
|
|
popl %ecx
|
|
popl %edx
|
|
|
|
call 1f
|
|
1: popl %esi
|
|
subl $1b, %esi
|
|
|
|
movl %ecx, efi32_config(%esi) /* Handle */
|
|
movl %edx, efi32_config+8(%esi) /* EFI System table pointer */
|
|
|
|
/* Relocate efi_config->call() */
|
|
leal efi32_config(%esi), %eax
|
|
add %esi, 40(%eax)
|
|
pushl %eax
|
|
2:
|
|
call efi_main
|
|
cmpl $0, %eax
|
|
movl %eax, %esi
|
|
jne 2f
|
|
fail:
|
|
/* EFI init failed, so hang. */
|
|
hlt
|
|
jmp fail
|
|
2:
|
|
movl BP_code32_start(%esi), %eax
|
|
leal startup_32(%eax), %eax
|
|
jmp *%eax
|
|
ENDPROC(efi32_stub_entry)
|
|
#endif
|
|
|
|
.text
|
|
.Lrelocated:
|
|
|
|
/*
|
|
* Clear BSS (stack is currently empty)
|
|
*/
|
|
xorl %eax, %eax
|
|
leal _bss(%ebx), %edi
|
|
leal _ebss(%ebx), %ecx
|
|
subl %edi, %ecx
|
|
shrl $2, %ecx
|
|
rep stosl
|
|
|
|
/*
|
|
* Adjust our own GOT
|
|
*/
|
|
leal _got(%ebx), %edx
|
|
leal _egot(%ebx), %ecx
|
|
1:
|
|
cmpl %ecx, %edx
|
|
jae 2f
|
|
addl %ebx, (%edx)
|
|
addl $4, %edx
|
|
jmp 1b
|
|
2:
|
|
|
|
/*
|
|
* Do the extraction, and jump to the new kernel..
|
|
*/
|
|
/* push arguments for extract_kernel: */
|
|
pushl $z_output_len /* decompressed length, end of relocs */
|
|
|
|
movl BP_init_size(%esi), %eax
|
|
subl $_end, %eax
|
|
movl %ebx, %ebp
|
|
subl %eax, %ebp
|
|
pushl %ebp /* output address */
|
|
|
|
pushl $z_input_len /* input_len */
|
|
leal input_data(%ebx), %eax
|
|
pushl %eax /* input_data */
|
|
leal boot_heap(%ebx), %eax
|
|
pushl %eax /* heap area */
|
|
pushl %esi /* real mode pointer */
|
|
call extract_kernel /* returns kernel location in %eax */
|
|
addl $24, %esp
|
|
|
|
/*
|
|
* Jump to the extracted kernel.
|
|
*/
|
|
xorl %ebx, %ebx
|
|
jmp *%eax
|
|
|
|
#ifdef CONFIG_EFI_STUB
|
|
.data
|
|
efi32_config:
|
|
.fill 5,8,0
|
|
.long efi_call_phys
|
|
.long 0
|
|
.byte 0
|
|
#endif
|
|
|
|
/*
|
|
* Stack and heap for uncompression
|
|
*/
|
|
.bss
|
|
.balign 4
|
|
boot_heap:
|
|
.fill BOOT_HEAP_SIZE, 1, 0
|
|
boot_stack:
|
|
.fill BOOT_STACK_SIZE, 1, 0
|
|
boot_stack_end:
|