*/
.hidden _bss
.hidden _ebss
- .hidden _got
- .hidden _egot
.hidden _end
__HEAD
+
+/*
+ * This macro gives the relative virtual address of X, i.e. the offset of X
+ * from startup_32. This is the same as the link-time virtual address of X,
+ * since startup_32 is at 0, but defining it this way tells the
+ * assembler/linker that we do not want the actual run-time address of X. This
+ * prevents the linker from trying to create unwanted run-time relocation
+ * entries for the reference when the compressed kernel is linked as PIE.
+ *
+ * A reference X(%reg) will result in the link-time VA of X being stored with
+ * the instruction, and a run-time R_X86_64_RELATIVE relocation entry that
+ * adds the 64-bit base address where the kernel is loaded.
+ *
+ * Replacing it with (X-startup_32)(%reg) results in the offset being stored,
+ * and no run-time relocation.
+ *
+ * The macro should be used as a displacement with a base register containing
+ * the run-time address of startup_32 [i.e. rva(X)(%reg)], or as an immediate
+ * [$ rva(X)].
+ *
+ * This macro can only be used from within the .head.text section, since the
+ * expression requires startup_32 to be in the same section as the code being
+ * assembled.
+ */
+#define rva(X) ((X) - startup_32)
+
.code32
SYM_FUNC_START(startup_32)
/*
leal (BP_scratch+4)(%esi), %esp
call 1f
1: popl %ebp
- subl $1b, %ebp
+ subl $ rva(1b), %ebp
/* Load new GDT with the 64bit segments using 32bit descriptor */
- leal gdt(%ebp), %eax
+ leal rva(gdt)(%ebp), %eax
movl %eax, 2(%eax)
lgdt (%eax)
movl %eax, %ss
/* setup a stack and make sure cpu supports long mode. */
- leal boot_stack_end(%ebp), %esp
+ leal rva(boot_stack_end)(%ebp), %esp
call verify_cpu
testl %eax, %eax
* image_offset = startup_32 - image_base
* Otherwise image_offset will be zero and has no effect on the calculations.
*/
- subl image_offset(%ebp), %ebx
+ subl rva(image_offset)(%ebp), %ebx
#endif
movl BP_kernel_alignment(%esi), %eax
/* Target address to relocate to for decompression */
addl BP_init_size(%esi), %ebx
- subl $_end, %ebx
+ subl $ rva(_end), %ebx
/*
* Prepare for entering 64 bit mode
1:
/* Initialize Page tables to 0 */
- leal pgtable(%ebx), %edi
+ leal rva(pgtable)(%ebx), %edi
xorl %eax, %eax
movl $(BOOT_INIT_PGT_SIZE/4), %ecx
rep stosl
/* Build Level 4 */
- leal pgtable + 0(%ebx), %edi
+ leal rva(pgtable + 0)(%ebx), %edi
leal 0x1007 (%edi), %eax
movl %eax, 0(%edi)
addl %edx, 4(%edi)
/* Build Level 3 */
- leal pgtable + 0x1000(%ebx), %edi
+ leal rva(pgtable + 0x1000)(%ebx), %edi
leal 0x1007(%edi), %eax
movl $4, %ecx
1: movl %eax, 0x00(%edi)
jnz 1b
/* Build Level 2 */
- leal pgtable + 0x2000(%ebx), %edi
+ leal rva(pgtable + 0x2000)(%ebx), %edi
movl $0x00000183, %eax
movl $2048, %ecx
1: movl %eax, 0(%edi)
jnz 1b
/* Enable the boot page tables */
- leal pgtable(%ebx), %eax
+ leal rva(pgtable)(%ebx), %eax
movl %eax, %cr3
/* Enable Long mode in EFER (Extended Feature Enable Register) */
* We place all of the values on our mini stack so lret can
* used to perform that far jump.
*/
- leal startup_64(%ebp), %eax
+ leal rva(startup_64)(%ebp), %eax
#ifdef CONFIG_EFI_MIXED
- movl efi32_boot_args(%ebp), %edi
+ movl rva(efi32_boot_args)(%ebp), %edi
cmp $0, %edi
jz 1f
- leal efi64_stub_entry(%ebp), %eax
- movl efi32_boot_args+4(%ebp), %esi
- movl efi32_boot_args+8(%ebp), %edx // saved bootparams pointer
+ leal rva(efi64_stub_entry)(%ebp), %eax
+ movl rva(efi32_boot_args+4)(%ebp), %esi
+ movl rva(efi32_boot_args+8)(%ebp), %edx // saved bootparams pointer
cmpl $0, %edx
jnz 1f
/*
* the correct stack alignment for entry.
*/
subl $40, %esp
- leal efi_pe_entry(%ebp), %eax
+ leal rva(efi_pe_entry)(%ebp), %eax
movl %edi, %ecx // MS calling convention
movl %esi, %edx
1:
call 1f
1: pop %ebp
- subl $1b, %ebp
+ subl $ rva(1b), %ebp
- movl %esi, efi32_boot_args+8(%ebp)
+ movl %esi, rva(efi32_boot_args+8)(%ebp)
SYM_INNER_LABEL(efi32_pe_stub_entry, SYM_L_LOCAL)
- movl %ecx, efi32_boot_args(%ebp)
- movl %edx, efi32_boot_args+4(%ebp)
- movb $0, efi_is64(%ebp)
+ movl %ecx, rva(efi32_boot_args)(%ebp)
+ movl %edx, rva(efi32_boot_args+4)(%ebp)
+ movb $0, rva(efi_is64)(%ebp)
/* Save firmware GDTR and code/data selectors */
- sgdtl efi32_boot_gdt(%ebp)
- movw %cs, efi32_boot_cs(%ebp)
- movw %ds, efi32_boot_ds(%ebp)
+ sgdtl rva(efi32_boot_gdt)(%ebp)
+ movw %cs, rva(efi32_boot_cs)(%ebp)
+ movw %ds, rva(efi32_boot_ds)(%ebp)
/* Disable paging */
movl %cr0, %eax
/* Target address to relocate to for decompression */
movl BP_init_size(%rsi), %ebx
- subl $_end, %ebx
+ subl $ rva(_end), %ebx
addq %rbp, %rbx
/* Set up the stack */
- leaq boot_stack_end(%rbx), %rsp
-
- /*
- * paging_prepare() and cleanup_trampoline() below can have GOT
- * references. Adjust the table with address we are running at.
- *
- * Zero RAX for adjust_got: the GOT was not adjusted before;
- * there's no adjustment to undo.
- */
- xorq %rax, %rax
-
- /*
- * Calculate the address the binary is loaded at and use it as
- * a GOT adjustment.
- */
- call 1f
-1: popq %rdi
- subq $1b, %rdi
-
- call .Ladjust_got
+ leaq rva(boot_stack_end)(%rbx), %rsp
/*
* At this point we are in long mode with 4-level paging enabled,
lretq
trampoline_return:
/* Restore the stack, the 32-bit trampoline uses its own stack */
- leaq boot_stack_end(%rbx), %rsp
+ leaq rva(boot_stack_end)(%rbx), %rsp
/*
* cleanup_trampoline() would restore trampoline memory.
* this function call.
*/
pushq %rsi
- leaq top_pgtable(%rbx), %rdi
+ leaq rva(top_pgtable)(%rbx), %rdi
call cleanup_trampoline
popq %rsi
pushq $0
popfq
- /*
- * Previously we've adjusted the GOT with address the binary was
- * loaded at. Now we need to re-adjust for relocation address.
- *
- * Calculate the address the binary is loaded at, so that we can
- * undo the previous GOT adjustment.
- */
- call 1f
-1: popq %rax
- subq $1b, %rax
-
- /* The new adjustment is the relocation address */
- movq %rbx, %rdi
- call .Ladjust_got
-
/*
* Copy the compressed kernel to the end of our buffer
* where decompression in place becomes safe.
*/
pushq %rsi
leaq (_bss-8)(%rip), %rsi
- leaq (_bss-8)(%rbx), %rdi
- movq $_bss /* - $startup_32 */, %rcx
- shrq $3, %rcx
+ leaq rva(_bss-8)(%rbx), %rdi
+ movl $(_bss - startup_32), %ecx
+ shrl $3, %ecx
std
rep movsq
cld
* during extract_kernel below. To avoid any issues, repoint the GDTR
* to the new copy of the GDT.
*/
- leaq gdt64(%rbx), %rax
- leaq gdt(%rbx), %rdx
+ leaq rva(gdt64)(%rbx), %rax
+ leaq rva(gdt)(%rbx), %rdx
movq %rdx, 2(%rax)
lgdt (%rax)
/*
* Jump to the relocated address.
*/
- leaq .Lrelocated(%rbx), %rax
+ leaq rva(.Lrelocated)(%rbx), %rax
jmp *%rax
SYM_CODE_END(startup_64)
movq %rdx, %rbx /* save boot_params pointer */
call efi_main
movq %rbx,%rsi
- leaq startup_64(%rax), %rax
+ leaq rva(startup_64)(%rax), %rax
jmp *%rax
SYM_FUNC_END(efi64_stub_entry)
SYM_FUNC_END_ALIAS(efi_stub_entry)
movq %rsi, %rdi /* real mode address */
leaq boot_heap(%rip), %rsi /* malloc area for uncompression */
leaq input_data(%rip), %rdx /* input_data */
- movl $z_input_len, %ecx /* input_len */
+ movl input_len(%rip), %ecx /* input_len */
movq %rbp, %r8 /* output target address */
- movl $z_output_len, %r9d /* decompressed length, end of relocs */
+ movl output_len(%rip), %r9d /* decompressed length, end of relocs */
call extract_kernel /* returns kernel location in %rax */
popq %rsi
jmp *%rax
SYM_FUNC_END(.Lrelocated)
-/*
- * Adjust the global offset table
- *
- * RAX is the previous adjustment of the table to undo (use 0 if it's the
- * first time we touch GOT).
- * RDI is the new adjustment to apply.
- */
-.Ladjust_got:
- /* Walk through the GOT adding the address to the entries */
- leaq _got(%rip), %rdx
- leaq _egot(%rip), %rcx
-1:
- cmpq %rcx, %rdx
- jae 2f
- subq %rax, (%rdx) /* Undo previous adjustment */
- addq %rdi, (%rdx) /* Apply the new adjustment */
- addq $8, %rdx
- jmp 1b
-2:
- ret
-
.code32
/*
* This is the 32-bit trampoline that will be copied over to low memory.
#define BS32_handle_protocol 88 // offsetof(efi_boot_services_32_t, handle_protocol)
#define LI32_image_base 32 // offsetof(efi_loaded_image_32_t, image_base)
- .text
+ __HEAD
.code32
SYM_FUNC_START(efi32_pe_entry)
/*
call 1f
1: pop %ebx
- subl $1b, %ebx
+ subl $ rva(1b), %ebx
/* Get the loaded image protocol pointer from the image handle */
leal -4(%ebp), %eax
pushl %eax // &loaded_image
- leal loaded_image_proto(%ebx), %eax
+ leal rva(loaded_image_proto)(%ebx), %eax
pushl %eax // pass the GUID address
pushl 8(%ebp) // pass the image handle
* use it before we get to the 64-bit efi_pe_entry() in C code.
*/
subl %esi, %ebx
- movl %ebx, image_offset(%ebp) // save image_offset
+ movl %ebx, rva(image_offset)(%ebp) // save image_offset
jmp efi32_pe_stub_entry
2: popl %edi // restore callee-save registers
projects / linux-2.6-microblaze.git / blobdiff